quite a lot of changes that I, of course, are not going to describe;)

41 files changed, 1263 insertions, 1851 deletions

diff --git a/advanced_lighting/1.blinn_phong/blinn_phong.c b/advanced_lighting/1.blinn_phong/blinn_phong.c
index 6bbd70a..404df05 100644
--- a/advanced_lighting/1.blinn_phong/blinn_phong.c
+++ b/advanced_lighting/1.blinn_phong/blinn_phong.c
@@ -1,258 +1,134 @@
-#include "pwyazh.h"
-
 #include "GL/glew.h"
 #include "GLFW/glfw3.h"
 
+#include "pwyazh.h"
 #include "pwyazh_GL.h"
 
 #include "common.h"
 
-static S32 global_width = 1024, global_height = 768;
-static Input global_input;
-static V3F camera_dp = (V3F){ 0.0f, 0.0f, 0.0f };
-static V3F light_pos = (V3F){ 0.0f, 0.0f, 0.0f };
-static S32 blinn = 0;
-
-void
-key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
+int main(void)
 {
-    switch (action)
-    {
-        case GLFW_PRESS: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_PRESS;
-                } break;
-            }
-        } break;
-        
-        case GLFW_RELEASE: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_RELEASE;
-                } break;
-            }
-        } break;
-    }
-}
+	GLFWwindow *window;
+	State state;
+	S32 width, height;
+	Input input;
+	Arena *arena;
+	F64 time, last_time;
+	U32 texture;
+	S32 blinn = 0;
+	V3F light_pos = (V3F){ 0.0f, 0.0f, 0.0f };
 
-void
-resize_callback(GLFWwindow* window, int width, int height)
-{
-    global_width = width;
-    global_height = height;
-    glViewport(0, 0, global_width, global_height);
-}
+	glfwSetErrorCallback(error_callback);
 
-void
-error_callback(int error, const char *desc)
-{
-    fprintf(stderr, "[ERROR] GLFW: %s\n", desc);
-}
+	if (glfwInit() == GLFW_FALSE)
+		return(1);
 
-void
-update(State *state)
-{
-    V3F camera_dv = get_dv_camera_orbital(&global_input, state->camera.pos,
-                                          v3f_zero(), state->dt, 2.0f);
-    if (key_is_pressed(global_input.action_up)) {
-        camera_dv = v3f_scalef(camera_dv, 3.0f);
-    }
-    camera_dp = v3f_add(camera_dp, camera_dv);
-    camera_dp = v3f_scalef(camera_dp, 0.7f);
-    state->camera.pos = v3f_add(state->camera.pos, camera_dp);
-    
-    if (key_first_press(global_input.jump))
-        blinn = blinn ? 0 : 1;
-    
-    input_update_last_state(&global_input);
-}
+	width = 1024;
+	height = 768;
 
-void
-render(State *state, U32 *shaders, U32 texture, Mesh **meshes)
-{
-    MAT4 projection, view, model;
-    U32 shader;
-    Mesh *mesh;
-    
-    glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
-    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-    
-    projection = perspective(state->camera.fovx, (F32)global_width/(F32)global_height,
-                             state->camera.near, state->camera.far);
-    view = look_at(state->camera.pos, v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
-    model = mat4_identity();
-    
-    U32 mesh_index = 0;
-    shader = shaders[mesh_index];
-    mesh = meshes[mesh_index];
-    glUseProgram(shader);
-    shader_set_mat4fv(shader, "projection", projection);
-    shader_set_mat4fv(shader, "view", view);
-    shader_set_mat4fv(shader, "model", model);
-    glActiveTexture(GL_TEXTURE0);
-    glBindTexture(GL_TEXTURE_2D, texture);
-    shader_set_3fv(shader, "light_pos", light_pos);
-    shader_set_3fv(shader, "view_pos", state->camera.pos);
-    shader_set_1i(shader, "blinn", blinn);
-    mesh_draw(mesh);
-    mesh_index++;
-
-    shader = shaders[mesh_index];
-    mesh = meshes[mesh_index];
-    glUseProgram(shader);
-    shader_set_mat4fv(shader, "projection", projection);
-    shader_set_mat4fv(shader, "view", view);
-    model = mat4_make_scale(v3f(0.1f, 0.1f, 0.1f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(mesh);
-
-    glBindTexture(GL_TEXTURE_2D, 0);
-}
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+	glfwWindowHint(GLFW_SAMPLES, 4);
+	window = glfwCreateWindow(width, height, "Blinn-Phong shading", 0, 0);
+	if (!window)
+		goto error;
 
-int
-main(void)
-{
-    GLFWwindow *window;
-    Arena *arena;
-    State state;
-    Mesh *meshes[2];
-    U32 shaders[2];
-    F64 time, last_time;
-    U32 texture;
-    
-    glfwSetErrorCallback(error_callback);
-    
-    if (glfwInit() == GLFW_FALSE)
-        return(1);
-    
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-    glfwWindowHint(GLFW_SAMPLES, 4);
-    window = glfwCreateWindow(global_width, global_height, "Blinn-Phong shading", 0, 0);
-    if (!window)
-        goto error;
-    
-    glfwSetKeyCallback(window, key_callback);
-    glfwSetWindowSizeCallback(window, resize_callback);
-    
-    glfwMakeContextCurrent(window);
-    
-    if (glewInit() != GLEW_OK)
-        goto error;
-    
-    glEnable(GL_DEPTH_TEST);
-    glEnable(GL_MULTISAMPLE);
-    
-    /* NOTE(pryazha): init */
-    arena = arena_alloc(Megabytes(64));
-    
-    state.camera = (Camera){ v3f(0.0f, 0.0f, 3.0f), 90.0f, 0.1f, 1000.0f };
-
-    Vertex vertices[] = {
-        // positions            // normals         // texcoords
-        vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
-        vertex(v3f(-10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 0.0f)),
-        vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
-
-        vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
-        vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
-        vertex(v3f( 10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 10.0f))
-    };
-    U32 indices[] = { 0, 1, 2, 3, 4, 5 };
-    meshes[0] = mesh_init(arena, vertices, 6, indices, 6);
-    meshes[1] = mesh_load_obj(arena, "../../data/models/cube.obj");
-    
-    shaders[0] = create_shader_program("shaders/blinn_phong.vs", "shaders/blinn_phong.fs");
-    shaders[1] = create_shader_program("shaders/light.vs", "shaders/light.fs");
-    
-    texture = load_texture("../../data/textures/wood.png");
-    
-    last_time = glfwGetTime();
-    
-    while (!glfwWindowShouldClose(window))
-    {
-        glfwPollEvents();
-        if (key_first_press(global_input.exit))
-            glfwSetWindowShouldClose(window, GLFW_TRUE);
-        update(&state);
-        render(&state, shaders, texture, meshes);
-        glfwSwapBuffers(window);
-        
-        time = glfwGetTime();
-        state.dt = time-last_time;
-        last_time = time;
-#if 0
-        fprintf(stdout, "[INFO]: dt: %f\n", state.dt);
-#endif
-    }
-    
-    glfwTerminate();
-    return(0);
-    
-    error:
-    glfwTerminate();
-    return(1);
+	glfwMakeContextCurrent(window);
+
+	if (glewInit() != GLEW_OK)
+		goto error;
+
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_MULTISAMPLE);
+
+	/* NOTE(pryazha): init */
+	arena = arena_alloc(Megabytes(64));
+
+	state.camera = (Camera){ v3f(0.0f, 0.0f, 3.0f), 90.0f, 0.1f, 1000.0f, 0.0f, 0.0f };
+
+	Vertex vertices[] = {
+		// positions            // normals         // texcoords
+		vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
+		vertex(v3f(-10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 0.0f)),
+		vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
+
+		vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
+		vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
+		vertex(v3f( 10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 10.0f))
+	};
+	U32 indices[] = { 0, 1, 2, 3, 4, 5 };
+	Mesh *quad = mesh_init(arena, vertices, 6, indices, 6);
+	Mesh *cube = mesh_load_obj(arena, "../../data/models/cube.obj");
+
+	U32 blinn_phong_shader = create_shader_program("shaders/blinn_phong.vert", "shaders/blinn_phong.frag");
+	U32 light_shader = create_shader_program("shaders/light.vert", "shaders/light.frag");
+
+	texture = load_texture("../../data/textures/wood.png");
+
+	last_time = glfwGetTime();
+
+	while (!glfwWindowShouldClose(window)) {
+		glfwPollEvents();
+
+		/* INFO(pryazha): Update */
+		process_glfw_keyboard(window, &input);
+		glfwGetFramebufferSize(window, &width, &height);
+
+		V3F target = v3f_zero();
+
+		if (key_first_press(input.exit))
+			glfwSetWindowShouldClose(window, GLFW_TRUE);
+
+		if (key_first_press(input.jump))
+			blinn = blinn ? 0 : 1;
+
+		V3F dv = get_dv_camera_orbital(&input, state.camera.pos,
+					       target, state.dt, 3.0f);
+		state.camera.pos = v3f_add(state.camera.pos, dv);
+
+		input_update_last_state(&input);
+
+		/* NOTE(pryazha): Render */
+		MAT4 proj, view, model;
+
+		view = look_at(state.camera.pos, target, v3f(0.0f, 1.0f, 0.0f));
+		proj = perspective(state.camera.fovx, (F32)width/(F32)height,
+				   state.camera.near, state.camera.far);
+		model = mat4_identity();
+
+		glViewport(0, 0, width, height);
+		glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+		glUseProgram(blinn_phong_shader);
+		shader_set_mat4fv(blinn_phong_shader, "proj", proj);
+		shader_set_mat4fv(blinn_phong_shader, "view", view);
+		shader_set_mat4fv(blinn_phong_shader, "model", model);
+		glActiveTexture(GL_TEXTURE0);
+		glBindTexture(GL_TEXTURE_2D, texture);
+		shader_set_3fv(blinn_phong_shader, "light_pos", light_pos);
+		shader_set_3fv(blinn_phong_shader, "view_pos", state.camera.pos);
+		shader_set_1i(blinn_phong_shader, "blinn", blinn);
+		mesh_draw(quad);
+
+		glUseProgram(light_shader);
+		shader_set_mat4fv(light_shader, "proj", proj);
+		shader_set_mat4fv(light_shader, "view", view);
+		model = mat4_make_scale(v3f(0.1f, 0.1f, 0.1f));
+		shader_set_mat4fv(light_shader, "model", model);
+		mesh_draw(cube);
+
+		glfwSwapBuffers(window);
+
+		time = glfwGetTime();
+		state.dt = time-last_time;
+		last_time = time;
+	}
+
+	glfwTerminate();
+	return(0);
+
+error:
+	glfwTerminate();
+	return(1);
 }
diff --git a/advanced_lighting/1.blinn_phong/shaders/blinn_phong.fs b/advanced_lighting/1.blinn_phong/shaders/blinn_phong.frag
index 5c66b3e..80f3e47 100644
--- a/advanced_lighting/1.blinn_phong/shaders/blinn_phong.fs
+++ b/advanced_lighting/1.blinn_phong/shaders/blinn_phong.frag
@@ -13,8 +13,7 @@ uniform vec3 light_pos;
 uniform vec3 view_pos;
 uniform bool blinn;
 
-void
-main(void)
+void main(void)
 {
     vec3 light_dir = normalize(light_pos-fs_in.frag_pos);
     vec3 view_dir = normalize(view_pos-fs_in.frag_pos);
@@ -25,13 +24,10 @@ main(void)
     float diff = max(dot(normal, light_dir), 0.0);
 
     float spec = 0.0;
-    if (blinn)
-    {
+    if (blinn) {
         vec3 halfway_dir = normalize(light_dir+view_dir);
         spec = pow(max(dot(normal, halfway_dir), 0.0), 16.0);
-    }
-    else
-    {
+    } else {
         vec3 reflect_dir = reflect(-light_dir, normal);
         spec = pow(max(dot(view_dir, reflect_dir), 0.0), 8.0);
     }
diff --git a/advanced_lighting/2.gamma_correction/shaders/blinn_phong.vs b/advanced_lighting/1.blinn_phong/shaders/blinn_phong.vert
index 4d1b792..870e7dc 100644
--- a/advanced_lighting/2.gamma_correction/shaders/blinn_phong.vs
+++ b/advanced_lighting/1.blinn_phong/shaders/blinn_phong.vert
@@ -9,15 +9,14 @@ out VS_OUT {
     vec2 tex_coords;
 } vs_out;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
     vs_out.frag_pos = vec3(model*vec4(apos, 1.0));
     vs_out.normal = mat3(transpose(inverse(model)))*anormal;
     vs_out.tex_coords = atex_coords;
-    gl_Position = projection*view*model*vec4(apos, 1.0);
+    gl_Position = proj*view*model*vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/2.gamma_correction/shaders/light.fs b/advanced_lighting/1.blinn_phong/shaders/light.frag
index bd00d82..c01da99 100644
--- a/advanced_lighting/2.gamma_correction/shaders/light.fs
+++ b/advanced_lighting/1.blinn_phong/shaders/light.frag
@@ -2,8 +2,7 @@
 
 out vec4 frag_color;
 
-void
-main(void)
+void main(void)
 {
     frag_color = vec4(1.0);
 }
diff --git a/advanced_lighting/2.gamma_correction/shaders/light.vs b/advanced_lighting/1.blinn_phong/shaders/light.vert
index ade669b..a8b1247 100644
--- a/advanced_lighting/2.gamma_correction/shaders/light.vs
+++ b/advanced_lighting/1.blinn_phong/shaders/light.vert
@@ -1,12 +1,11 @@
 #version 330 core
 layout(location = 0) in vec3 apos;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
-    gl_Position = projection*view*model*vec4(apos, 1.0);
+    gl_Position = proj*view*model*vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/2.gamma_correction/gamma_correction.c b/advanced_lighting/2.gamma_correction/gamma_correction.c
index 68edae7..a027722 100644
--- a/advanced_lighting/2.gamma_correction/gamma_correction.c
+++ b/advanced_lighting/2.gamma_correction/gamma_correction.c
@@ -1,297 +1,171 @@
-#include "pwyazh.h"
-
 #include "GL/glew.h"
 #include "GLFW/glfw3.h"
 
+#include "pwyazh.h"
 #include "pwyazh_GL.h"
 
 #include "common.h"
 
-static S32 global_width = 1024, global_height = 768;
-static Input global_input;
-static V3F camera_dp = (V3F){ 0.0f, 0.0f, 0.0f };
-static V3F light_pos = (V3F){ 0.0f, 0.0f, 0.0f };
-static U32 gamma_correction = 0;
-
-static V3F light_positions[] = {
-    (V3F){-3.0f, 0.0f, 0.0f},
-    (V3F){-1.0f, 0.0f, 0.0f},
-    (V3F){1.0f, 0.0f, 0.0f},
-    (V3F){3.0f, 0.0f, 0.0}
-};
-static V3F light_colors[] = {
-    (V3F){0.25f, 0.25f, 0.25f},
-    (V3F){0.50f, 0.50f, 0.50f},
-    (V3F){0.75f, 0.75f, 0.75f},
-    (V3F){1.0f, 1.0f, 1.0}
-};
-
-void
-key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
-{
-    switch (action)
-    {
-        case GLFW_PRESS: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_PRESS;
-                } break;
-            }
-        } break;
-        
-        case GLFW_RELEASE: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_RELEASE;
-                } break;
-            }
-        } break;
-    }
-}
-
-void
-resize_callback(GLFWwindow* window, int width, int height)
-{
-    global_width = width;
-    global_height = height;
-    glViewport(0, 0, global_width, global_height);
-}
-
-void
-error_callback(int error, const char *desc)
-{
-    fprintf(stderr, "[ERROR] GLFW: %s\n", desc);
-}
-
-void
-update(State *state)
-{
-    V3F camera_dv = get_dv_camera_orbital(&global_input, state->camera.pos,
-                                          v3f_zero(), state->dt, 2.0f);
-    if (key_is_pressed(global_input.action_up))
-        camera_dv = v3f_scalef(camera_dv, 3.0f);
-    camera_dp = v3f_add(camera_dp, camera_dv);
-    camera_dp = v3f_scalef(camera_dp, 0.7f);
-    state->camera.pos = v3f_add(state->camera.pos, camera_dp);
-
-    if (key_first_press(global_input.action_right))
-        gamma_correction = !gamma_correction;
-
-    F32 time = glfwGetTime();
-    for (S32 position_index = 0;
-         position_index < (S32)ArrayCount(light_positions);
-         position_index++)
-    {
-        F32 radius = position_index*2.0+2.0;
-        F32 angle = time*position_index*pi_F32/6.0;
-        F32 x = f32_sin(angle)*radius;
-        F32 z = f32_cos(angle)*radius;
-        light_positions[position_index] = v3f(x, light_positions[position_index].y, z);
-    }
-    
-    input_update_last_state(&global_input);
-}
-
-void
-render(State *state, U32 *shaders, U32 texture, U32 texture_gamma_corrected, Mesh **meshes)
-{
-    MAT4 projection, view, model;
-    U32 shader;
-    Mesh *mesh;
-
-    glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
-    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-    
-    projection = perspective(state->camera.fovx, (F32)global_width/(F32)global_height,
-                             state->camera.near, state->camera.far);
-    view = look_at(state->camera.pos, v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
-    model = mat4_identity();
-    
-    U32 mesh_index = 0;
-    shader = shaders[mesh_index];
-    mesh = meshes[mesh_index];
-    glUseProgram(shader);
-    shader_set_mat4fv(shader, "projection", projection);
-    shader_set_mat4fv(shader, "view", view);
-    shader_set_mat4fv(shader, "model", model);
-    if (gamma_correction)
-        glBindTexture(GL_TEXTURE_2D, texture_gamma_corrected);
-    else
-        glBindTexture(GL_TEXTURE_2D, texture);
-    shader_set_3fv(shader, "light_pos", light_pos);
-    shader_set_3fv(shader, "view_pos", state->camera.pos);
-    shader_set_1i(shader, "gamma_correction", gamma_correction);
-    U32 light_positions_location = glGetUniformLocation(shader, "light_positions");
-    glUniform3fv(light_positions_location, 4, (F32 *)&light_positions[0]);
-    U32 light_colors_location = glGetUniformLocation(shader, "light_colors");
-        glUniform3fv(light_colors_location, 4, (F32 *)&light_colors[0]);
-    mesh_draw(mesh);
-    mesh_index++;
-
-    shader = shaders[mesh_index];
-    mesh = meshes[mesh_index];
-    glUseProgram(shader);
-    shader_set_mat4fv(shader, "projection", projection);
-    shader_set_mat4fv(shader, "view", view);
-    for (S32 light_index = 0;
-         light_index < (S32)ArrayCount(light_positions);
-         light_index++)
-    {
-        model = mat4_make_scale(v3f(0.1f, 0.1f, 0.1f));
-        model = mat4_translate(model, light_positions[light_index]);
-        shader_set_mat4fv(shader, "model", model);
-        mesh_draw(mesh);
-    }
-    glBindTexture(GL_TEXTURE_2D, 0);
-}
-
-int
-main(void)
+int main(void)
 {
-    GLFWwindow *window;
-    Arena *arena;
-    State state;
-    Mesh *meshes[2];
-    U32 shaders[2];
-    F64 time, last_time;
-    U32 texture, texture_gamma_corrected;
-    
-    glfwSetErrorCallback(error_callback);
-    
-    if (glfwInit() == GLFW_FALSE)
-        return(1);
-    
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-    glfwWindowHint(GLFW_SAMPLES, 4);
-    window = glfwCreateWindow(global_width, global_height, "Gamma correction", 0, 0);
-    if (!window)
-        goto error;
-    
-    glfwSetKeyCallback(window, key_callback);
-    glfwSetWindowSizeCallback(window, resize_callback);
-    
-    glfwMakeContextCurrent(window);
-    
-    if (glewInit() != GLEW_OK)
-        goto error;
-    
-    glEnable(GL_DEPTH_TEST);
-    glEnable(GL_MULTISAMPLE);
-    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-    /* NOTE(pryazha): A less controlled method of applying gamma correction */
-    /* glEnable(GL_FRAMEBUFFER_SRGB); */
-    
-    /* NOTE(pryazha): init */
-    arena = arena_alloc(Megabytes(64));
-    
-    state.camera = (Camera){ v3f(0.0f, 0.0f, 3.0f), 90.0f, 0.1f, 1000.0f };
-
-    Vertex vertices[] = {
-        // positions            // normals         // texcoords
-        vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
-        vertex(v3f(-10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 0.0f)),
-        vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
-
-        vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
-        vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
-        vertex(v3f( 10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 10.0f))
-    };
-    U32 indices[] = { 0, 1, 2, 3, 4, 5 };
-    meshes[0] = mesh_init(arena, vertices, 6, indices, 6);
-    meshes[1] = mesh_load_obj(arena, "../../data/models/cube.obj");
-    
-    shaders[0] = create_shader_program("shaders/blinn_phong.vs", "shaders/blinn_phong.fs");
-    shaders[1] = create_shader_program("shaders/light.vs", "shaders/light.fs");
-    
-    texture = load_texture_gamma("../../data/textures/wood.png", 0);
-    texture_gamma_corrected = load_texture_gamma("../../data/textures/wood.png", 1);
-    
-    last_time = glfwGetTime();
-    
-    while (!glfwWindowShouldClose(window))
-    {
-        glfwPollEvents();
-        if (key_first_press(global_input.exit))
-            glfwSetWindowShouldClose(window, GLFW_TRUE);
-        update(&state);
-        render(&state, shaders, texture, texture_gamma_corrected, meshes);
-        glfwSwapBuffers(window);
-        
-        time = glfwGetTime();
-        state.dt = time-last_time;
-        last_time = time;
-#if 0
-        fprintf(stdout, "[INFO]: dt: %f\n", state.dt);
-#endif
-    }
-    
-    glfwTerminate();
-    return(0);
-    
-    error:
-    glfwTerminate();
-    return(1);
+	GLFWwindow *window;
+	Arena *arena;
+	State state;
+	Input input;
+	F64 time, last_time;
+	V3F light_pos = (V3F){ 0.0f, 0.0f, 0.0f };
+	U32 gamma_correction = 0;
+	MAT4 proj, view, model;
+	S32 width, height;
+	B32 blinn;
+
+	V3F light_positions[] = {
+		(V3F){-3.0f, 0.0f, 0.0f},
+		(V3F){-1.0f, 0.0f, 0.0f},
+		(V3F){1.0f, 0.0f, 0.0f},
+		(V3F){3.0f, 0.0f, 0.0}
+	};
+	V3F light_colors[] = {
+		(V3F){0.25f, 0.25f, 0.25f},
+		(V3F){0.50f, 0.50f, 0.50f},
+		(V3F){0.75f, 0.75f, 0.75f},
+		(V3F){1.0f, 1.0f, 1.0}
+	};
+
+	glfwSetErrorCallback(error_callback);
+
+	if (glfwInit() == GLFW_FALSE)
+		return(1);
+
+	width = 1024;
+	height = 768;
+
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+	glfwWindowHint(GLFW_SAMPLES, 4);
+	window = glfwCreateWindow(width, height, "Gamma correction", 0, 0);
+	if (!window)
+		goto error;
+
+	glfwMakeContextCurrent(window);
+
+	if (glewInit() != GLEW_OK)
+		goto error;
+
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_MULTISAMPLE);
+	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+	/* NOTE(pryazha): A less controlled method of applying gamma correction */
+	/* glEnable(GL_FRAMEBUFFER_SRGB); */
+
+	/* NOTE(pryazha): init */
+	arena = arena_alloc(Megabytes(64));
+
+	state.camera = (Camera){ v3f(0.0f, 0.0f, 3.0f), 90.0f, 0.1f, 1000.0f, 0.0f, 0.0f };
+
+	Vertex vertices[] = {
+		// positions            // normals         // texcoords
+		vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
+		vertex(v3f(-10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 0.0f)),
+		vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
+
+		vertex(v3f( 10.0f,  -0.5f,  10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 0.0f)),
+		vertex(v3f(-10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f( 0.0f, 10.0f)),
+		vertex(v3f( 10.0f,  -0.5f, -10.0f), v3f(0.0f, 1.0f, 0.0f), v2f(10.0f, 10.0f))
+	};
+	U32 indices[] = { 0, 1, 2, 3, 4, 5 };
+	Mesh *quad = mesh_init(arena, vertices, 6, indices, 6);
+	Mesh *cube = mesh_load_obj(arena, "../../data/models/cube.obj");
+
+	U32 blinn_phong_shader = create_shader_program("shaders/blinn_phong.vert", "shaders/blinn_phong.frag");
+	U32 light_shader = create_shader_program("shaders/light.vert", "shaders/light.frag");
+
+	U32 texture = load_texture_gamma("../../data/textures/wood.png", 0);
+	U32 texture_gamma_corrected = load_texture_gamma("../../data/textures/wood.png", 1);
+
+	last_time = glfwGetTime();
+
+	while (!glfwWindowShouldClose(window)) {
+		glfwPollEvents();
+
+		/* NOTE(pryazha): Update */
+		process_glfw_keyboard(window, &input);
+		glfwGetFramebufferSize(window, &width, &height);
+
+		V3F target = v3f_zero();
+
+		if (key_first_press(input.exit))
+			glfwSetWindowShouldClose(window, GLFW_TRUE);
+
+		if (key_first_press(input.jump))
+			blinn = blinn ? 0 : 1;
+
+		V3F dv = get_dv_camera_orbital(&input, state.camera.pos,
+					       target, state.dt, 3.0f);
+		state.camera.pos = v3f_add(state.camera.pos, dv);
+
+		if (key_first_press(input.action_right))
+			gamma_correction = !gamma_correction;
+
+		for (S32 i = 0; i < (S32)ArrayCount(light_positions); i++) {
+			F32 radius = i*2.0+2.0;
+			F32 angle = time*i*pi_F32/6.0;
+			F32 x = f32_sin(angle)*radius;
+			F32 z = f32_cos(angle)*radius;
+			light_positions[i] = v3f(x, light_positions[i].y, z);
+		}
+
+		input_update_last_state(&input);
+
+		proj = perspective(state.camera.fovx, (F32)width/(F32)height,
+					 state.camera.near, state.camera.far);
+		view = look_at(state.camera.pos, v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
+		model = mat4_identity();
+
+		/* NOTE(pryazha): Render */
+		glViewport(0, 0, width, height);
+		glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+		glUseProgram(blinn_phong_shader);
+		shader_set_mat4fv(blinn_phong_shader, "proj", proj);
+		shader_set_mat4fv(blinn_phong_shader, "view", view);
+		shader_set_mat4fv(blinn_phong_shader, "model", model);
+		if (gamma_correction)
+			glBindTexture(GL_TEXTURE_2D, texture_gamma_corrected);
+		else
+			glBindTexture(GL_TEXTURE_2D, texture);
+		shader_set_3fv(blinn_phong_shader, "light_pos", light_pos);
+		shader_set_3fv(blinn_phong_shader, "view_pos", state.camera.pos);
+		shader_set_1i(blinn_phong_shader, "gamma_correction", gamma_correction);
+		U32 light_positions_location = glGetUniformLocation(blinn_phong_shader, "light_positions");
+		glUniform3fv(light_positions_location, 4, (F32 *)&light_positions[0]);
+		U32 light_colors_location = glGetUniformLocation(blinn_phong_shader, "light_colors");
+		glUniform3fv(light_colors_location, 4, (F32 *)&light_colors[0]);
+		mesh_draw(quad);
+
+		glUseProgram(light_shader);
+		shader_set_mat4fv(light_shader, "proj", proj);
+		shader_set_mat4fv(light_shader, "view", view);
+		for (S32 i = 0; i < (S32)ArrayCount(light_positions); i++) {
+			model = mat4_make_scale(v3f(0.1f, 0.1f, 0.1f));
+			model = mat4_translate(model, light_positions[i]);
+			shader_set_mat4fv(light_shader, "model", model);
+			mesh_draw(cube);
+		}
+		glBindTexture(GL_TEXTURE_2D, 0);
+
+		glfwSwapBuffers(window);
+
+		time = glfwGetTime();
+		state.dt = time-last_time;
+		last_time = time;
+	}
+
+	glfwTerminate();
+	return(0);
+
+error:
+	glfwTerminate();
+	return(1);
 }
diff --git a/advanced_lighting/2.gamma_correction/shaders/blinn_phong.fs b/advanced_lighting/2.gamma_correction/shaders/blinn_phong.frag
index 35e701c..331fc8b 100644
--- a/advanced_lighting/2.gamma_correction/shaders/blinn_phong.fs
+++ b/advanced_lighting/2.gamma_correction/shaders/blinn_phong.frag
@@ -14,9 +14,8 @@ uniform vec3 light_colors[4];
 uniform vec3 view_pos;
 uniform bool gamma_correction;
 
-vec3
-blinn_phong(vec3 light_dir, vec3 view_dir, vec3 normal,
-            vec3 light_pos, vec3 light_color)
+vec3 blinn_phong(vec3 light_dir, vec3 view_dir, vec3 normal,
+		vec3 light_pos, vec3 light_color)
 {
     float diff = max(dot(normal, light_dir), 0.0);
     vec3 diffuse = diff*light_color;
@@ -31,16 +30,14 @@ blinn_phong(vec3 light_dir, vec3 view_dir, vec3 normal,
     return((diffuse+specular)*attenuation);
 }
 
-void
-main(void)
+void main(void)
 {
     vec3 view_dir = normalize(view_pos-fs_in.frag_pos);
     vec3 normal = normalize(fs_in.normal);
     vec3 texture_color = texture(texture0, fs_in.tex_coords).rgb;
 
     vec3 lighting = vec3(0.0);
-    for (int i = 0; i < 4; i++)
-    {
+    for (int i = 0; i < 4; i++) {
         vec3 light_pos = light_positions[i];
         vec3 light_color = light_colors[i];
         vec3 light_dir = normalize(light_pos-fs_in.frag_pos);
diff --git a/advanced_lighting/1.blinn_phong/shaders/blinn_phong.vs b/advanced_lighting/2.gamma_correction/shaders/blinn_phong.vert
index 4d1b792..870e7dc 100644
--- a/advanced_lighting/1.blinn_phong/shaders/blinn_phong.vs
+++ b/advanced_lighting/2.gamma_correction/shaders/blinn_phong.vert
@@ -9,15 +9,14 @@ out VS_OUT {
     vec2 tex_coords;
 } vs_out;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
     vs_out.frag_pos = vec3(model*vec4(apos, 1.0));
     vs_out.normal = mat3(transpose(inverse(model)))*anormal;
     vs_out.tex_coords = atex_coords;
-    gl_Position = projection*view*model*vec4(apos, 1.0);
+    gl_Position = proj*view*model*vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/color.fs b/advanced_lighting/2.gamma_correction/shaders/light.frag
index bd00d82..c01da99 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/color.fs
+++ b/advanced_lighting/2.gamma_correction/shaders/light.frag
@@ -2,8 +2,7 @@
 
 out vec4 frag_color;
 
-void
-main(void)
+void main(void)
 {
     frag_color = vec4(1.0);
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/color.vs b/advanced_lighting/2.gamma_correction/shaders/light.vert
index ade669b..a8b1247 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/color.vs
+++ b/advanced_lighting/2.gamma_correction/shaders/light.vert
@@ -1,12 +1,11 @@
 #version 330 core
 layout(location = 0) in vec3 apos;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
-    gl_Position = projection*view*model*vec4(apos, 1.0);
+    gl_Position = proj*view*model*vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/build.sh b/advanced_lighting/3.1.shadow_mapping/build.sh
index bba445d..79ca088 100755
--- a/advanced_lighting/3.1.shadow_mapping/build.sh
+++ b/advanced_lighting/3.1.shadow_mapping/build.sh
@@ -2,4 +2,4 @@
 . ../../config
 TARGET='shadow_mapping'
 set -x
-gcc -o $TARGET $CFLAGS $INCLUDE $LFLAGS $TARGET.c $LIBS
+gcc -o $TARGET $CFLAGS $INCLUDE $LFLAGS $TARGET.c $LIBS && ./$TARGET
diff --git a/advanced_lighting/1.blinn_phong/shaders/light.fs b/advanced_lighting/3.1.shadow_mapping/shaders/color.frag
index bd00d82..c01da99 100644
--- a/advanced_lighting/1.blinn_phong/shaders/light.fs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/color.frag
@@ -2,8 +2,7 @@
 
 out vec4 frag_color;
 
-void
-main(void)
+void main(void)
 {
     frag_color = vec4(1.0);
 }
diff --git a/advanced_lighting/1.blinn_phong/shaders/light.vs b/advanced_lighting/3.1.shadow_mapping/shaders/color.vert
index ade669b..6aa621e 100644
--- a/advanced_lighting/1.blinn_phong/shaders/light.vs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/color.vert
@@ -1,12 +1,11 @@
 #version 330 core
 layout(location = 0) in vec3 apos;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
-    gl_Position = projection*view*model*vec4(apos, 1.0);
+	gl_Position = proj * view * model * vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.fs b/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.frag
index d250894..4cb6df1 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.fs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.frag
@@ -8,15 +8,13 @@ uniform sampler2D depth_map;
 uniform float near;
 uniform float far;
 
-float
-linearize_depth(float depth)
+float linearize_depth(float depth)
 {
     float z = (depth+1.0)*0.5;
     return((2.0*near*far)/(far+near-z*(far-near)));
 }
 
-void
-main(void)
+void main(void)
 {
     float depth = texture(depth_map, tex_coords).r;
 
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.vs b/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.vert
index 5717608..5717608 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.vs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/debug_quad.vert
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/shadow.fs b/advanced_lighting/3.1.shadow_mapping/shaders/shadow.frag
index 1c7018a..3403d1d 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/shadow.fs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/shadow.frag
@@ -15,8 +15,7 @@ uniform vec3 view_pos;
 uniform sampler2D diffuse_texture;
 uniform sampler2D shadow_map;
 
-float
-calculate_shadow()
+float calculate_shadow()
 {
     vec3 proj_coords = fs_in.frag_pos_light_space.xyz/fs_in.frag_pos_light_space.w;
     proj_coords = proj_coords*0.5+0.5;
@@ -43,8 +42,7 @@ calculate_shadow()
     return(shadow);
 }
 
-void
-main(void)
+void main(void)
 {
     vec3 color = texture(diffuse_texture, fs_in.tex_coords).rgb;
     vec3 normal = normalize(fs_in.normal);
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/shadow.vs b/advanced_lighting/3.1.shadow_mapping/shaders/shadow.vert
index 3ecd5b1..3f14663 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/shadow.vs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/shadow.vert
@@ -10,17 +10,16 @@ out VS_OUT {
     vec2 tex_coords;
 } vs_out;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 uniform mat4 light_space_matrix;
 
-void
-main(void)
+void main(void)
 {
     vs_out.frag_pos = vec3(model*vec4(apos, 1.0));
     vs_out.frag_pos_light_space = light_space_matrix*vec4(vs_out.frag_pos, 1.0);
     vs_out.normal = mat3(transpose(inverse(model)))*anormal;
     vs_out.tex_coords = atex_coords;
-    gl_Position = projection*view*vec4(vs_out.frag_pos, 1.0);
+    gl_Position = proj*view*vec4(vs_out.frag_pos, 1.0);
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.fs b/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.frag
index 16b9908..d99aab2 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.fs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.frag
@@ -1,6 +1,5 @@
 #version 330 core
 
-void
-main(void)
+void main(void)
 {
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.vs b/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.vert
index b9752ed..d3adca9 100644
--- a/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.vs
+++ b/advanced_lighting/3.1.shadow_mapping/shaders/simple_depth.vert
@@ -4,8 +4,7 @@ layout(location = 0) in vec3 apos;
 uniform mat4 light_space_matrix;
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
     gl_Position = light_space_matrix*model*vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/3.1.shadow_mapping/shadow_mapping.c b/advanced_lighting/3.1.shadow_mapping/shadow_mapping.c
index 7f03415..fd03ed9 100644
--- a/advanced_lighting/3.1.shadow_mapping/shadow_mapping.c
+++ b/advanced_lighting/3.1.shadow_mapping/shadow_mapping.c
@@ -1,417 +1,275 @@
-#include "pwyazh.h"
-
 #include "GL/glew.h"
 #include "GLFW/glfw3.h"
 
+#include "pwyazh.h"
 #include "pwyazh_GL.h"
 
 #include "common.h"
 
-static S32 global_screen_width = 800, global_screen_height = 600;
-static U32 global_shadow_width = 1024, global_shadow_height = 1024;
-
-static Input global_input;
-
-static V3F camera_dp = (V3F){ 0.0f, 0.0f, 0.0f };
-
-static U32 global_depth_map_fbo, global_depth_map;
-
-static U32 global_debug_quad_shader, global_simple_depth_shader,
-           global_shadow_shader, global_color_shader;
-
-static U32 global_wood_texture;
-
-static U32 global_quad_vao;
-
-static U32 shadows_ortho = 1;
-
-static V3F light_pos;
-
-void
-glfw_key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
-{
-    switch (action)
-    {
-        case GLFW_PRESS: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_DOWN: {
-                    global_input.action_down.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_PRESS;
-                } break;
-            }
-        } break;
-        
-        case GLFW_RELEASE: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_DOWN: {
-                    global_input.action_down.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_RELEASE;
-                } break;
-            }
-        } break;
-    }
-}
-
-void
-resize_callback(GLFWwindow* window, int width, int height)
-{
-    global_screen_width = width;
-    global_screen_height = height;
-    glViewport(0, 0, global_screen_width, global_screen_height);
-}
-
-void
-error_callback(int error, const char *desc)
-{
-    fprintf(stderr, "[ERROR] GLFW: %s\n", desc);
-}
-
-void
-update(State *state, F32 time)
-{
-    F32 radius;
-
-    V3F camera_dv = get_dv_camera_orbital(&global_input, state->camera.pos,
-                                          v3f_zero(), state->dt, 2.0f);
-    if (key_is_pressed(global_input.action_up))
-        camera_dv = v3f_scalef(camera_dv, 3.0f);
-    camera_dp = v3f_add(camera_dp, camera_dv);
-    camera_dp = v3f_scalef(camera_dp, 0.8f);
-    state->camera.pos = v3f_add(state->camera.pos, camera_dp);
-
-    if (key_first_press(global_input.action_down))
-        shadows_ortho = !shadows_ortho;
-    
-    input_update_last_state(&global_input);
-
-    F32 x, z, angular_speed;
-
-    angular_speed = 1.0f;
-    radius = 4.0f;
-    x = f32_sin(time*angular_speed)*radius;
-    z = f32_cos(time*angular_speed)*radius;
-
-    light_pos = v3f(x, 4.0f, z);
-}
-
-void
-render_scene(U32 shader, Mesh *cube, Mesh *plane)
-{
-    MAT4 model;
-
-    model = mat4_identity();
-    shader_set_mat4fv(shader, "model", model); 
-    mesh_draw(plane);
-
-    /*
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(10.0f, 0.1f, 10.0f));
-    model = mat4_translate(model, v3f(0.0f, -0.6f, 0.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-    */
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
-    model = mat4_translate(model, v3f(0.0f, 1.5f, 0.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
-    model = mat4_translate(model, v3f(2.0f, 0.0f, 1.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.25f, 0.25f, 0.25f));
-    model = mat4_rotate_angles(model, v3f(60.0f, 0.0f, 0.0f));
-    model = mat4_translate(model, v3f(-1.0f, 0.0f, 2.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-}
-
-void
-render(State *state, Mesh *cube, Mesh *plane)
+void render_scene(U32 shader, Mesh *cube, Mesh *plane)
 {
-    /* MAT4 projection, view, model; */
-    MAT4 light_projection, light_view, model;
-    F32 near, far, fovx;
-    V3F target, up;
-
-    if (shadows_ortho)
-    {
-        near = 1.0f;
-        far = 10.0f;
-        F32 half_side = 10.0f;
-        light_projection = ortho(-half_side, half_side, -half_side, half_side, near, far);
-    }
-    else
-    {
-        fovx = 90.0f;
-        near = 1.0f;
-        far = 50.0f;
-        light_projection = perspective(fovx, (F32)global_shadow_width/(F32)global_shadow_height,
-                                       near, far);
-    }
-
-    target = v3f_zero();
-    up = v3f(0.0f, 1.0f, 0.0f);
-    light_view = look_at(light_pos, target, up);
-    MAT4 light_space_matrix = mat4_mul(light_projection, light_view);
-
-    glUseProgram(global_simple_depth_shader);
-    shader_set_mat4fv(global_simple_depth_shader, "light_space_matrix", light_space_matrix); 
-    glViewport(0, 0, global_shadow_width, global_shadow_height);
-    glBindFramebuffer(GL_FRAMEBUFFER, global_depth_map_fbo);
-    glClear(GL_DEPTH_BUFFER_BIT);
-    // glCullFace(GL_FRONT);
-    render_scene(global_simple_depth_shader, cube, plane);
-    // glCullFace(GL_BACK);
-    glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-    glViewport(0, 0, global_screen_width, global_screen_height);
-    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
-    MAT4 projection = perspective(state->camera.fovx, (F32)global_screen_width/(F32)global_screen_height,
-                                  state->camera.near, state->camera.far);
-    MAT4 view = look_at(state->camera.pos, v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
-    glUseProgram(global_shadow_shader);
-    shader_set_mat4fv(global_shadow_shader, "projection", projection); 
-    shader_set_mat4fv(global_shadow_shader, "view", view);
-
-    shader_set_3fv(global_shadow_shader, "light_pos", light_pos);
-    shader_set_3fv(global_shadow_shader, "view_pos", state->camera.pos);
-    shader_set_mat4fv(global_shadow_shader, "light_space_matrix", light_space_matrix); 
-    glActiveTexture(GL_TEXTURE0);
-    glBindTexture(GL_TEXTURE_2D, global_wood_texture);
-    glActiveTexture(GL_TEXTURE1);
-    glBindTexture(GL_TEXTURE_2D, global_depth_map);
-    render_scene(global_shadow_shader, cube, plane);
-
-    glUseProgram(global_color_shader);
-    shader_set_mat4fv(global_shadow_shader, "projection", projection); 
-    shader_set_mat4fv(global_shadow_shader, "view", view);
-    model = mat4_make_scale(v3f(0.1f, 0.1f, 0.1f));
-    model = mat4_translate(model, light_pos);
-    shader_set_mat4fv(global_shadow_shader, "model", model);
-    mesh_draw(cube);
-
-    glDisable(GL_DEPTH_TEST);
-    glUseProgram(global_debug_quad_shader);
-    F32 scale = 0.3f;
-    Transform transform = transform_make_scale_translate(v3f(scale, scale, scale),
-                                                         v3f(1.0f-scale, 1.0f-scale, 0.0f));
-    model = transform_apply(transform);
-    shader_set_mat4fv(global_debug_quad_shader, "model", model);
-    shader_set_1f(global_debug_quad_shader, "near", near);
-    shader_set_1f(global_debug_quad_shader, "far", far);
-    glActiveTexture(GL_TEXTURE0);
-    glBindTexture(GL_TEXTURE_2D, global_depth_map);
-    glBindVertexArray(global_quad_vao);
-    glDrawArrays(GL_TRIANGLES, 0, 6);
-    glBindVertexArray(0);
-    glEnable(GL_DEPTH_TEST);
+	MAT4 model;
+
+	model = mat4_identity();
+	shader_set_mat4fv(shader, "model", model); 
+	mesh_draw(plane);
+
+	/*
+	   model = mat4_identity();
+	   model = mat4_make_scale(v3f(10.0f, 0.1f, 10.0f));
+	   model = mat4_translate(model, v3f(0.0f, -0.6f, 0.0f));
+	   shader_set_mat4fv(shader, "model", model);
+	   mesh_draw(cube);
+	   */
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
+	model = mat4_translate(model, v3f(0.0f, 1.5f, 0.0f));
+	shader_set_mat4fv(shader, "model", model);
+	mesh_draw(cube);
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
+	model = mat4_translate(model, v3f(2.0f, 0.0f, 1.0f));
+	shader_set_mat4fv(shader, "model", model);
+	mesh_draw(cube);
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(0.25f, 0.25f, 0.25f));
+	model = mat4_rotate_angles(model, v3f(60.0f, 0.0f, 0.0f));
+	model = mat4_translate(model, v3f(-1.0f, 0.0f, 2.0f));
+	shader_set_mat4fv(shader, "model", model);
+	mesh_draw(cube);
 }
 
-int
-main(void)
+int main(void)
 {
-    GLFWwindow *window;
-    Arena *arena;
-    State state;
-    Mesh *cube_mesh, *plane_mesh;
-    F64 time, last_time;
-    
-    glfwSetErrorCallback(error_callback);
-    
-    if (glfwInit() == GLFW_FALSE)
-        return(1);
-    
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-    glfwWindowHint(GLFW_SAMPLES, 4);
-    window = glfwCreateWindow(global_screen_width, global_screen_height, "Shadow mapping", 0, 0);
-    if (!window)
-        goto error;
-    
-    glfwSetKeyCallback(window, glfw_key_callback);
-    glfwSetWindowSizeCallback(window, resize_callback);
-    
-    glfwMakeContextCurrent(window);
-    
-    if (glewInit() != GLEW_OK)
-        goto error;
-    
-    glEnable(GL_DEPTH_TEST);
-    // glEnable(GL_CULL_FACE);
-    
-    /* NOTE(pryazha): Init */
-    arena = arena_alloc(Megabytes(64));
-    
-    state.camera = (Camera){ v3f(0.0f, 1.0f, 3.0f), 90.0f, 0.1f, 100.0f };
-    light_pos = v3f(-2.0f, 4.0f, -2.0f);
-
-    /* NOTE(pryazha): Meshes */
-    Vertex plane_vertices[] = {
-        // positions            // normals         // texcoords
-        vertex(v3f(-25.0f, -0.5f,  25.0f),  v3f(0.0f, 1.0f, 0.0f),   v2f(0.0f,  0.0f)),
-        vertex(v3f(25.0f, -0.5f,  25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f(25.0f,  0.0f)),
-        vertex(v3f(-25.0f, -0.5f, -25.0f),  v3f(0.0f, 1.0f, 0.0f),   v2f(0.0f, 25.0f)),
-
-        vertex(v3f(25.0f, -0.5f,  25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f(25.0f,  0.0f)),
-        vertex(v3f(25.0f, -0.5f, -25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f(25.0f, 25.0f)),
-        vertex(v3f(-25.0f, -0.5f, -25.0f),  v3f(0.0f, 1.0f, 0.0f),   v2f(0.0f, 25.0f)),
-    };
-    U32 indices[] = { 0, 1, 2, 3, 4, 5 };
-    plane_mesh = mesh_init(arena, plane_vertices, ArrayCount(plane_vertices), indices, ArrayCount(indices));
-    cube_mesh = mesh_load_obj(arena, "../../data/models/cube.obj");
-    
-    F32 quad_vertices[] = {
-        -1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
-         1.0f, -1.0f,  0.0f,   1.0f, 0.0f,
-         1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
-        -1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
-         1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
-        -1.0f,  1.0f,  0.0f,   0.0f, 1.0f
-    };
-    
-    U32 vbo;    
-    glGenVertexArrays(1, &global_quad_vao);
-    glBindVertexArray(global_quad_vao);
-    glGenBuffers(1, &vbo);
-    glBindBuffer(GL_ARRAY_BUFFER, vbo);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), quad_vertices, GL_STATIC_DRAW);
-    glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)0);
-    glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)(3*sizeof(F32)));
-    glBindVertexArray(0);
-
-    /* NOTE(pryazha): Shaders */
-    global_debug_quad_shader = create_shader_program("shaders/debug_quad.vs",
-                                                     "shaders/debug_quad.fs");
-    global_simple_depth_shader = create_shader_program("shaders/simple_depth.vs",
-                                                       "shaders/simple_depth.fs");
-    global_shadow_shader = create_shader_program("shaders/shadow.vs", "shaders/shadow.fs");
-    global_color_shader = create_shader_program("shaders/color.vs", "shaders/color.fs");
-    
-    glUseProgram(global_shadow_shader);
-    shader_set_1i(global_shadow_shader, "diffuse_texture", 0);
-    shader_set_1i(global_shadow_shader, "shadow_map", 1);
-    glUseProgram(0);
-
-    global_wood_texture = load_texture_gamma("../../data/textures/wood.png", 1);
-
-    glGenFramebuffers(1, &global_depth_map_fbo);
-    glGenTextures(1, &global_depth_map);
-    glBindTexture(GL_TEXTURE_2D, global_depth_map);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, global_shadow_width,
-                 global_shadow_height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
-    glBindFramebuffer(GL_FRAMEBUFFER, global_depth_map_fbo);
-    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D,
-                           global_depth_map, 0);
-    V4F border_color = v4f(1.0f, 1.0f, 1.0f, 1.0f);
-    glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, (const F32 *)&border_color);
-    glDrawBuffer(GL_NONE);
-    glReadBuffer(GL_NONE);
-    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
-        fprintf(stderr, "[ERROR]: Failed to complete depth map framebuffer.\n");
-    glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-    last_time = glfwGetTime();
-    
-    while (!glfwWindowShouldClose(window))
-    {
-        glfwPollEvents();
-        if (key_first_press(global_input.exit))
-            glfwSetWindowShouldClose(window, GLFW_TRUE);
-        update(&state, time);
-        render(&state, cube_mesh, plane_mesh);
-        glfwSwapBuffers(window);
-        
-        time = glfwGetTime();
-        state.dt = time-last_time;
-        last_time = time;
-#if 0
-        fprintf(stdout, "[INFO]: dt: %f\n", state.dt);
-#endif
-    }
-
-    glfwTerminate();
-    return(0);
-    
-    error:
-    glfwTerminate();
-    return(1);
+	GLFWwindow *window;
+	Arena *arena;
+	State state;
+	F64 time, last_time;
+	S32 screen_width = 800, screen_height = 600;
+	U32 shadow_width = 1024, shadow_height = 1024;
+	Input input;
+	U32 shadows_ortho = 1;
+	V3F light_pos = v3f(-2.0f, 4.0f, -2.0f);
+
+	glfwSetErrorCallback(error_callback);
+
+	if (glfwInit() == GLFW_FALSE)
+		return(1);
+
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+	glfwWindowHint(GLFW_SAMPLES, 4);
+	window = glfwCreateWindow(screen_width, screen_height, "Shadow mapping", 0, 0);
+	if (!window)
+		goto error;
+
+	glfwMakeContextCurrent(window);
+
+	if (glewInit() != GLEW_OK)
+		goto error;
+
+	glEnable(GL_DEPTH_TEST);
+	// glEnable(GL_CULL_FACE);
+
+	/* NOTE(pryazha): Init */
+	arena = arena_alloc(Megabytes(64));
+
+	state.camera = (Camera){ v3f(0.0f, 1.0f, 3.0f), 90.0f, 0.1f, 100.0f, 0.0f, 0.0f };
+
+	/* NOTE(pryazha): Meshes */
+	Vertex plane_vertices[] = {
+		// positions            // normals         // texcoords
+		vertex(v3f(-25.0f, -0.5f,  25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f( 0.0f,  0.0f)),
+		vertex(v3f( 25.0f, -0.5f,  25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f(25.0f,  0.0f)),
+		vertex(v3f(-25.0f, -0.5f, -25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f( 0.0f, 25.0f)),
+
+		vertex(v3f( 25.0f, -0.5f,  25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f(25.0f,  0.0f)),
+		vertex(v3f( 25.0f, -0.5f, -25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f(25.0f, 25.0f)),
+		vertex(v3f(-25.0f, -0.5f, -25.0f),  v3f(0.0f, 1.0f, 0.0f),  v2f( 0.0f, 25.0f)),
+	};
+	U32 indices[] = { 0, 1, 2, 3, 4, 5 };
+	Mesh *plane = mesh_init(arena, plane_vertices, ArrayCount(plane_vertices),
+				indices, ArrayCount(indices));
+	Mesh *cube = mesh_load_obj(arena, "../../data/models/cube.obj");
+
+	F32 quad_vertices[] = {
+		-1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
+		1.0f, -1.0f,  0.0f,   1.0f, 0.0f,
+		1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
+		-1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
+		1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
+		-1.0f,  1.0f,  0.0f,   0.0f, 1.0f
+	};
+
+	U32 quad_vao, vbo;    
+	glGenVertexArrays(1, &quad_vao);
+	glBindVertexArray(quad_vao);
+	glGenBuffers(1, &vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), quad_vertices, GL_STATIC_DRAW);
+	glEnableVertexAttribArray(0);
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)0);
+	glEnableVertexAttribArray(1);
+	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)(3*sizeof(F32)));
+	glBindVertexArray(0);
+
+	/* NOTE(pryazha): Shaders */
+	U32 debug_quad_shader = create_shader_program("shaders/debug_quad.vert",
+						      "shaders/debug_quad.frag");
+	U32 simple_depth_shader = create_shader_program("shaders/simple_depth.vert",
+							"shaders/simple_depth.frag");
+	U32 shadow_shader = create_shader_program("shaders/shadow.vert",
+						  "shaders/shadow.frag");
+	U32 color_shader = create_shader_program("shaders/color.vert",
+						 "shaders/color.frag");
+
+	glUseProgram(shadow_shader);
+	shader_set_1i(shadow_shader, "diffuse_texture", 0);
+	shader_set_1i(shadow_shader, "shadow_map", 1);
+	glUseProgram(0);
+
+	U32 wood_texture = load_texture_gamma("../../data/textures/wood.png", 1);
+
+	U32 depth_map_fbo, depth_map;
+	glGenFramebuffers(1, &depth_map_fbo);
+	glGenTextures(1, &depth_map);
+	glBindTexture(GL_TEXTURE_2D, depth_map);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, shadow_width,
+		     shadow_height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+	glBindFramebuffer(GL_FRAMEBUFFER, depth_map_fbo);
+	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D,
+			       depth_map, 0);
+	V4F border_color = v4f(1.0f, 1.0f, 1.0f, 1.0f);
+	glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, (const F32 *)&border_color);
+	glDrawBuffer(GL_NONE);
+	glReadBuffer(GL_NONE);
+	if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+		fprintf(stderr, "[ERROR]: Failed to complete depth map framebuffer.\n");
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+	last_time = glfwGetTime();
+
+	while (!glfwWindowShouldClose(window)) {
+		glfwPollEvents();
+
+		/* NOTE(pryazha): Update */
+		process_glfw_keyboard(window, &input);
+		glfwGetFramebufferSize(window, &screen_width, &screen_height);
+
+		V3F target = v3f_zero();
+
+		if (key_first_press(input.exit))
+			glfwSetWindowShouldClose(window, GLFW_TRUE);
+
+		V3F dv = get_dv_camera_orbital(&input, state.camera.pos,
+					       target, state.dt, 3.0f);
+		state.camera.pos = v3f_add(state.camera.pos, dv);
+
+		if (key_first_press(input.action_down))
+			shadows_ortho = !shadows_ortho;
+
+		input_update_last_state(&input);
+
+		F32 radius, angular_speed, x, z;
+
+		angular_speed = 1.0f;
+		radius = 4.0f;
+		x = f32_sin(time*angular_speed)*radius;
+		z = f32_cos(time*angular_speed)*radius;
+
+		light_pos = v3f(x, 4.0f, z);
+
+		/* NOTE(pryazha): Render */
+		MAT4 proj, view, model, light_proj;
+		F32 fovx, near, far;
+
+		if (shadows_ortho) {
+			near = 1.0f;
+			far = 10.0f;
+			F32 half_side = 10.0f;
+			light_proj = ortho(-half_side, half_side, -half_side, half_side, near, far);
+		} else {
+			fovx = 90.0f;
+			near = 1.0f;
+			far = 50.0f;
+			light_proj = perspective(fovx, (F32)shadow_width/(F32)shadow_height,
+						 near, far);
+		}
+
+		V3F up = v3f(0.0f, 1.0f, 0.0f);
+		MAT4 light_view = look_at(light_pos, target, up);
+		MAT4 light_space_matrix = mat4_mul(light_proj, light_view);
+
+		glUseProgram(simple_depth_shader);
+		shader_set_mat4fv(simple_depth_shader, "light_space_matrix", light_space_matrix); 
+		glViewport(0, 0, shadow_width, shadow_height);
+		glBindFramebuffer(GL_FRAMEBUFFER, depth_map_fbo);
+		glClear(GL_DEPTH_BUFFER_BIT);
+		// glCullFace(GL_FRONT);
+		render_scene(simple_depth_shader, cube, plane);
+		// glCullFace(GL_BACK);
+		glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+		glViewport(0, 0, screen_width, screen_height);
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+		proj = perspective(state.camera.fovx, (F32)screen_width/(F32)screen_height, 
+				   state.camera.near, state.camera.far);
+		view = look_at(state.camera.pos, v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
+
+		glUseProgram(shadow_shader);
+		shader_set_mat4fv(shadow_shader, "proj", proj); 
+		shader_set_mat4fv(shadow_shader, "view", view);
+		shader_set_3fv(shadow_shader, "light_pos", light_pos);
+		shader_set_3fv(shadow_shader, "view_pos", state.camera.pos);
+		shader_set_mat4fv(shadow_shader, "light_space_matrix", light_space_matrix); 
+		glActiveTexture(GL_TEXTURE0);
+		glBindTexture(GL_TEXTURE_2D, wood_texture);
+		glActiveTexture(GL_TEXTURE1);
+		glBindTexture(GL_TEXTURE_2D, depth_map);
+		render_scene(shadow_shader, cube, plane);
+
+		glUseProgram(color_shader);
+		shader_set_mat4fv(shadow_shader, "proj", proj); 
+		shader_set_mat4fv(shadow_shader, "view", view);
+		model = mat4_make_scale(v3f(0.1f, 0.1f, 0.1f));
+		model = mat4_translate(model, light_pos);
+		shader_set_mat4fv(shadow_shader, "model", model);
+		mesh_draw(cube);
+
+		glDisable(GL_DEPTH_TEST);
+		glUseProgram(debug_quad_shader);
+		F32 scale = 0.3f;
+		Transform transform = transform_make_scale_translate(v3f(scale, scale, scale),
+								     v3f(1.0f-scale, 1.0f-scale, 0.0f));
+		model = transform_apply(transform);
+		shader_set_mat4fv(debug_quad_shader, "model", model);
+		shader_set_1f(debug_quad_shader, "near", near);
+		shader_set_1f(debug_quad_shader, "far", far);
+		glActiveTexture(GL_TEXTURE0);
+		glBindTexture(GL_TEXTURE_2D, depth_map);
+		glBindVertexArray(quad_vao);
+		glDrawArrays(GL_TRIANGLES, 0, 6);
+		glBindVertexArray(0);
+		glEnable(GL_DEPTH_TEST);
+		glfwSwapBuffers(window);
+
+		time = glfwGetTime();
+		state.dt = time-last_time;
+		last_time = time;
+	}
+
+	glfwTerminate();
+	return(0);
+
+error:
+	glfwTerminate();
+	return(1);
 }
diff --git a/advanced_lighting/3.2.point_shadows/point_shadows b/advanced_lighting/3.2.point_shadows/point_shadows
index c4668ab..452a2a2 100755
--- a/advanced_lighting/3.2.point_shadows/point_shadows
+++ b/advanced_lighting/3.2.point_shadows/point_shadows
diff --git a/advanced_lighting/3.2.point_shadows/point_shadows.c b/advanced_lighting/3.2.point_shadows/point_shadows.c
index 0f60565..e622f6c 100644
--- a/advanced_lighting/3.2.point_shadows/point_shadows.c
+++ b/advanced_lighting/3.2.point_shadows/point_shadows.c
@@ -1,383 +1,261 @@
-#include "pwyazh.h"
-
 #include "GL/glew.h"
 #include "GLFW/glfw3.h"
 
+#include "pwyazh.h"
 #include "pwyazh_GL.h"
 
 #include "common.h"
 
-static S32 global_screen_width = 800, global_screen_height = 600;
-static Input global_input;
-static B32 first_mouse = 1;
-
-void
-glfw_key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
-{
-    switch (action)
-    {
-        case GLFW_PRESS: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_DOWN: {
-                    global_input.action_down.state = KeyState_PRESS;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_PRESS;
-                } break;
-            }
-        } break;
-        
-        case GLFW_RELEASE: {
-            switch (key)
-            {
-                case GLFW_KEY_D: {
-                    global_input.move_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_W: {
-                    global_input.move_forward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_A: {
-                    global_input.move_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_S: {
-                    global_input.move_backward.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_E: {
-                    global_input.move_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_Q: {
-                    global_input.move_down.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_SPACE: {
-                    global_input.jump.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_RIGHT: {
-                    global_input.action_right.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_UP: {
-                    global_input.action_up.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_LEFT: {
-                    global_input.action_left.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_DOWN: {
-                    global_input.action_down.state = KeyState_RELEASE;
-                } break;
-                case GLFW_KEY_ESCAPE: {
-                    global_input.exit.state = KeyState_RELEASE;
-                } break;
-            }
-        } break;
-    }
-}
-
-void
-resize_callback(GLFWwindow* window, int width, int height)
-{
-    global_screen_width = width;
-    global_screen_height = height;
-    /* glViewport(0, 0, global_screen_width, global_screen_height); */
-}
-
-void
-error_callback(int error, const char *desc)
-{
-    fprintf(stderr, "[ERROR] GLFW: %s\n", desc);
-}
-
-void
-cursor_pos_callback(GLFWwindow* window, double xpos, double ypos)
-{
-    if (first_mouse)
-    {
-        global_input.last_mouse_pos = v2f(xpos, ypos);
-        first_mouse = 0;
-    }
-    global_input.mouse_offset = v2f(global_input.mouse_offset.x+((F32)xpos-global_input.last_mouse_pos.x),
-                             global_input.mouse_offset.y+((F32)ypos-global_input.last_mouse_pos.y));
-    global_input.last_mouse_pos = v2f((F32)xpos, (F32)ypos);
-}
-
-
-void
-render_scene(U32 shader, Mesh *cube)
+void render_scene(U32 shader, Mesh *cube)
 {
-    MAT4 model;
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(5.0f, 5.0f, 5.0f));
-    shader_set_mat4fv(shader, "model", model);
-    glDisable(GL_CULL_FACE);
-    shader_set_1i(shader, "reverse_normals", 1);
-    mesh_draw(cube);
-    shader_set_1i(shader, "reverse_normals", 0);
-    glEnable(GL_CULL_FACE);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
-    model = mat4_translate(model, v3f(0.0f, 1.5f, 0.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
-    model = mat4_translate(model, v3f(2.0f, 0.0f, 1.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.25f, 0.25f, 0.25f));
-    model = mat4_rotate_angles(model, v3f(60.0f, 0.0f, 0.0f));
-    model = mat4_translate(model, v3f(-1.0f, 0.0f, 2.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
+	MAT4 model;
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(5.0f, 5.0f, 5.0f));
+	shader_set_mat4fv(shader, "model", model);
+	glDisable(GL_CULL_FACE);
+	shader_set_1i(shader, "reverse_normals", 1);
+	mesh_draw(cube);
+	shader_set_1i(shader, "reverse_normals", 0);
+	glEnable(GL_CULL_FACE);
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
+	model = mat4_translate(model, v3f(0.0f, 1.5f, 0.0f));
+	shader_set_mat4fv(shader, "model", model);
+	mesh_draw(cube);
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
+	model = mat4_translate(model, v3f(2.0f, 0.0f, 1.0f));
+	shader_set_mat4fv(shader, "model", model);
+	mesh_draw(cube);
+
+	model = mat4_identity();
+	model = mat4_make_scale(v3f(0.25f, 0.25f, 0.25f));
+	model = mat4_rotate_angles(model, v3f(60.0f, 0.0f, 0.0f));
+	model = mat4_translate(model, v3f(-1.0f, 0.0f, 2.0f));
+	shader_set_mat4fv(shader, "model", model);
+	mesh_draw(cube);
 }
 
-int
-main(void)
+int main(void)
 {
-    GLFWwindow *window;
-    Arena *arena;
-    State state;
-    Mesh *cube;
-    F64 time, last_time;
-    V3F light_pos;
-    MAT4 shadow_transforms[6];
-    MAT4 proj, view;
-    
-    glfwSetErrorCallback(error_callback);
-    
-    if (glfwInit() == GLFW_FALSE)
-        return(1);
-    
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-    glfwWindowHint(GLFW_SAMPLES, 4);
-    window = glfwCreateWindow(global_screen_width, global_screen_height, "Point shadows", 0, 0);
-    if (!window)
-        goto error;
-
-    glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
-    
-    glfwSetKeyCallback(window, glfw_key_callback);
-    glfwSetWindowSizeCallback(window, resize_callback);
-    glfwSetCursorPosCallback(window, cursor_pos_callback);
-    
-    glfwMakeContextCurrent(window);
-    
-    if (glewInit() != GLEW_OK)
-        goto error;
-    
-    glEnable(GL_DEPTH_TEST);
-    glEnable(GL_CULL_FACE);
-    
-    /* NOTE(pryazha): Init */
-    arena = arena_alloc(Megabytes(64));
-    
-    state.camera = (Camera){
-        .pos = v3f(0.0f, 1.0f, 3.0f),
-        .fovx = 100.0f,
-        .near = 0.1f,
-        .far = 100.0f,
-        .yaw = 0.0f,
-        .pitch = 0.0f
-    };
-    V3F camera_dp = v3f_zero();
-    /* light_pos = v3f(-2.0f, 4.0f, -2.0f); */
-    light_pos = v3f_zero();
-
-    /* NOTE(pryazha): Meshes */
-    cube = mesh_load_obj(arena, "../../data/models/cube.obj");
-    
-    F32 quad_vertices[] = {
-        -1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
-         1.0f, -1.0f,  0.0f,   1.0f, 0.0f,
-         1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
-        -1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
-         1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
-        -1.0f,  1.0f,  0.0f,   0.0f, 1.0f
-    };
-    U32 quad_vao, vbo;
-    glGenVertexArrays(1, &quad_vao);
-    glBindVertexArray(quad_vao);
-    glGenBuffers(1, &vbo);
-    glBindBuffer(GL_ARRAY_BUFFER, vbo);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), quad_vertices, GL_STATIC_DRAW);
-    glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)0);
-    glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)(3*sizeof(F32)));
-    glBindVertexArray(0);
-
-    /* NOTE(pryazha): Shaders */
-    U32 depth_shader = create_shader_program_geom("shaders/depth.vs",
-                                                  "shaders/depth.fs",
-                                                  "shaders/depth.gs");
-    U32 shadow_shader = create_shader_program("shaders/shadow.vs", "shaders/shadow.fs");
-    
-    glUseProgram(shadow_shader);
-    shader_set_1i(shadow_shader, "diffuse_texture", 0);
-    shader_set_1i(shadow_shader, "depth_cubemap", 1);
-    glUseProgram(0);
-
-    U32 wood_texture = load_texture_gamma("../../data/textures/wood.png", 0);
-
-    /* NOTE(pryazha): Depth framebuffer init */
-    U32 depth_cubemap_fbo, depth_cubemap;
-    U32 shadow_width = 1024, shadow_height = 1024;
-    glGenFramebuffers(1, &depth_cubemap_fbo);
-    glGenTextures(1, &depth_cubemap);
-    glBindTexture(GL_TEXTURE_CUBE_MAP, depth_cubemap);
-    for (U32 cubemap_side = 0; cubemap_side < 6; ++cubemap_side)
-        glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X+cubemap_side, 0, GL_DEPTH_COMPONENT,
-                     shadow_width, shadow_height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_BORDER);
-    glBindFramebuffer(GL_FRAMEBUFFER, depth_cubemap_fbo);
-    glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depth_cubemap, 0);
-    glDrawBuffer(GL_NONE);
-    glReadBuffer(GL_NONE);
-    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
-        fprintf(stderr, "[ERROR]: Failed to complete depth map framebuffer.\n");
-    glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-    last_time = glfwGetTime();
-    
-    while (!glfwWindowShouldClose(window))
-    {
-        glfwPollEvents();
-        if (key_first_press(global_input.exit))
-            glfwSetWindowShouldClose(window, GLFW_TRUE);
-
-        /* NOTE(pryazha): For now it's easier to write all of the logic in the main loop */
-        /* NOTE(pryazha): Update */
-        F32 x, y, z, angular_speed, radius;
-        V3F camera_dv;
-
-        camera_dv = get_dv_camera_first_person(&global_input, &state.camera,
-                                               1.0f, state.dt);
-        if (key_is_pressed(global_input.action_up))
-            camera_dv = v3f_scalef(camera_dv, 3.0f);
-        camera_dp = v3f_add(camera_dp, camera_dv);
-        camera_dp = v3f_scalef(camera_dp, 0.8f);
-        state.camera.pos = v3f_add(state.camera.pos, camera_dp);
-
-        F32 sensitivity = 0.1f;
-        global_input.mouse_offset = v2f_scalef(global_input.mouse_offset, sensitivity);
-        state.camera.yaw += global_input.mouse_offset.x;
-        state.camera.pitch += global_input.mouse_offset.y;
-        if (state.camera.pitch > 89.0f)
-            state.camera.pitch = 89.0f;
-        if (state.camera.pitch < -89.0f)
-            state.camera.pitch = -89.0f;
-
-        input_update_last_state(&global_input);
-
-        angular_speed = 1.0f;
-        radius = 4.0f;
-        x = f32_sin(time*angular_speed)*radius;
-        y = f32_sin(time*angular_speed)*f32_sin(time*angular_speed)*radius;
-        z = f32_cos(time*angular_speed)*radius;
-
-        light_pos = v3f(x, y, z);
-
-        /* NOTE(pryazha): Render */
-
-        /* NOTE(pryazha): Render the depth cubemap */
-        F32 fovx, aspect, near, far;
-        fovx = 90.0f;
-        aspect = (F32)shadow_width/(F32)shadow_height;
-        near = 1.0f;
-        far = 25.0f;
-        proj = perspective(fovx, aspect, near, far);
-        shadow_transforms[0] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 1.0f,  0.0f,  0.0f)), v3f(0.0f, -1.0f,  0.0f))); /* right */
-        shadow_transforms[1] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f(-1.0f,  0.0f,  0.0f)), v3f(0.0f, -1.0f,  0.0f))); /* left */
-        shadow_transforms[2] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  1.0f,  0.0f)), v3f(0.0f,  0.0f,  1.0f))); /* top */
-        shadow_transforms[3] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f, -1.0f,  0.0f)), v3f(0.0f,  0.0f, -1.0f))); /* bottom */
-        shadow_transforms[4] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  0.0f,  1.0f)), v3f(0.0f, -1.0f,  0.0f))); /* near */
-        shadow_transforms[5] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  0.0f, -1.0f)), v3f(0.0f, -1.0f,  0.0f))); /* far */
-        glViewport(0, 0, shadow_width, shadow_height);
-        glBindFramebuffer(GL_FRAMEBUFFER, depth_cubemap_fbo);
-        glClear(GL_DEPTH_BUFFER_BIT);
-        glUseProgram(depth_shader);
-        shader_set_1f(depth_shader, "far", far);
-        shader_set_3fv(depth_shader, "light_pos", light_pos);
-        for (U32 i = 0; i < 6; ++i)
-        {
-            char uniform_name[256];
-            snprintf(uniform_name, 256, "shadow_transforms[%d]", i);
-            shader_set_mat4fv(depth_shader, uniform_name, shadow_transforms[i]);
-        }
-        render_scene(depth_shader, cube);
-        glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-        /* NOTE(pryazha): Render the scene as normal */
-        glViewport(0, 0, global_screen_width, global_screen_height);
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
-        glUseProgram(shadow_shader);
-
-        aspect = (F32)global_screen_width/(F32)global_screen_height;
-        proj = perspective(state.camera.fovx, aspect, state.camera.near, state.camera.far);
-        view = get_view_matrix(&state.camera);
-
-        shader_set_mat4fv(shadow_shader, "projection", proj); 
-        shader_set_mat4fv(shadow_shader, "view", view);
-        shader_set_3fv(shadow_shader, "light_pos", light_pos);
-        shader_set_3fv(shadow_shader, "view_pos", state.camera.pos);
-        shader_set_1f(shadow_shader, "far", far);
-
-        glActiveTexture(GL_TEXTURE0);
-        glBindTexture(GL_TEXTURE_2D, wood_texture);
-        glActiveTexture(GL_TEXTURE1);
-        glBindTexture(GL_TEXTURE_CUBE_MAP, depth_cubemap);
-        render_scene(shadow_shader, cube);
-
-        glfwSwapBuffers(window);
-        
-        time = glfwGetTime();
-        state.dt = time-last_time;
-        last_time = time;
-    }
-
-    glfwTerminate();
-    return(0);
-    
-    error:
-    glfwTerminate();
-    return(1);
+	GLFWwindow *window;
+	Arena *arena;
+	State state;
+	Input input;
+	F64 time, last_time;
+	V3F light_pos;
+	MAT4 shadow_transforms[6];
+	MAT4 proj, view;
+	S32 screen_width, screen_height;
+
+	glfwSetErrorCallback(error_callback);
+
+	if (glfwInit() == GLFW_FALSE)
+		return(1);
+
+	screen_width = 800;
+	screen_height = 600;
+
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+	glfwWindowHint(GLFW_SAMPLES, 4);
+	window = glfwCreateWindow(screen_width, screen_height, "Point shadows", 0, 0);
+	if (!window)
+		goto error;
+
+	glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
+
+	glfwMakeContextCurrent(window);
+
+	if (glewInit() != GLEW_OK)
+		goto error;
+
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_CULL_FACE);
+
+	/* NOTE(pryazha): Init */
+	arena = arena_alloc(Megabytes(64));
+
+	state.camera = (Camera){
+		.pos = v3f(0.0f, 1.0f, 3.0f),
+			.fovx = 100.0f,
+			.near = 0.1f,
+			.far = 100.0f,
+			.yaw = 0.0f,
+			.pitch = 0.0f
+	};
+	V3F camera_dp = v3f_zero();
+	/* light_pos = v3f(-2.0f, 4.0f, -2.0f); */
+	light_pos = v3f_zero();
+
+	/* NOTE(pryazha): Meshes */
+	Mesh *cube = mesh_load_obj(arena, "../../data/models/cube.obj");
+
+	F32 quad_vertices[] = {
+		-1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
+		1.0f, -1.0f,  0.0f,   1.0f, 0.0f,
+		1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
+		-1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
+		1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
+		-1.0f,  1.0f,  0.0f,   0.0f, 1.0f
+	};
+	U32 quad_vao, vbo;
+	glGenVertexArrays(1, &quad_vao);
+	glBindVertexArray(quad_vao);
+	glGenBuffers(1, &vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), quad_vertices, GL_STATIC_DRAW);
+	glEnableVertexAttribArray(0);
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)0);
+	glEnableVertexAttribArray(1);
+	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)(3*sizeof(F32)));
+	glBindVertexArray(0);
+
+	/* NOTE(pryazha): Shaders */
+	U32 depth_shader = create_shader_program_geom("shaders/depth.vert",
+						      "shaders/depth.frag",
+						      "shaders/depth.geom");
+	U32 shadow_shader = create_shader_program("shaders/shadow.vert",
+						  "shaders/shadow.frag");
+
+	glUseProgram(shadow_shader);
+	shader_set_1i(shadow_shader, "diffuse_texture", 0);
+	shader_set_1i(shadow_shader, "depth_cubemap", 1);
+	glUseProgram(0);
+
+	U32 wood_texture = load_texture_gamma("../../data/textures/wood.png", 0);
+
+	/* NOTE(pryazha): Depth framebuffer init */
+	U32 depth_cubemap_fbo, depth_cubemap;
+	U32 shadow_width = 1024, shadow_height = 1024;
+	glGenFramebuffers(1, &depth_cubemap_fbo);
+	glGenTextures(1, &depth_cubemap);
+	glBindTexture(GL_TEXTURE_CUBE_MAP, depth_cubemap);
+	for (U32 cubemap_side = 0; cubemap_side < 6; ++cubemap_side)
+		glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X+cubemap_side, 0, GL_DEPTH_COMPONENT,
+			     shadow_width, shadow_height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_BORDER);
+	glBindFramebuffer(GL_FRAMEBUFFER, depth_cubemap_fbo);
+	glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depth_cubemap, 0);
+	glDrawBuffer(GL_NONE);
+	glReadBuffer(GL_NONE);
+	if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+		fprintf(stderr, "[ERROR]: Failed to complete depth map framebuffer.\n");
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+	last_time = glfwGetTime();
+
+	while (!glfwWindowShouldClose(window)) {
+		glfwPollEvents();
+
+		/* NOTE(pryazha): For now it's easier to write all of the logic in the main loop */
+		/* NOTE(pryazha): Update */
+		F32 x, y, z, angular_speed, radius;
+
+		glfwGetFramebufferSize(window, &screen_width, &screen_height);
+		process_glfw_keyboard(window, &input);
+		process_glfw_mouse_pos(window, &input);
+
+		if (key_first_press(input.exit))
+			glfwSetWindowShouldClose(window, GLFW_TRUE);
+
+		F32 speed = 4.0f;
+		V3F dv = get_dv_camera_first_person(&input, &state.camera,
+						    speed, state.dt);
+		if (key_is_pressed(input.action_up))
+			dv = v3f_scalef(dv, 3.0f);
+		camera_dp = v3f_add(camera_dp, dv);
+		camera_dp = v3f_scalef(camera_dp, 0.8f);
+		state.camera.pos = v3f_add(state.camera.pos, camera_dp);
+
+		F32 sensitivity = 0.1f;
+		input.mouse_offset = v2f_scalef(input.mouse_offset, sensitivity);
+		state.camera.yaw += input.mouse_offset.x;
+		state.camera.pitch += input.mouse_offset.y;
+		if (state.camera.pitch > 89.0f)
+			state.camera.pitch = 89.0f;
+		if (state.camera.pitch < -89.0f)
+			state.camera.pitch = -89.0f;
+
+		input_update_last_state(&input);
+
+		angular_speed = 1.0f;
+		radius = 4.0f;
+		x = f32_sin(time*angular_speed)*radius;
+		y = f32_sin(time*angular_speed)*f32_sin(time*angular_speed)*radius;
+		z = f32_cos(time*angular_speed)*radius;
+
+		light_pos = v3f(x, y, z);
+
+		/* NOTE(pryazha): Render */
+
+		/* NOTE(pryazha): Render the depth cubemap */
+		F32 fovx, aspect, near, far;
+		fovx = 90.0f;
+		aspect = (F32)shadow_width/(F32)shadow_height;
+		near = 1.0f;
+		far = 25.0f;
+		proj = perspective(fovx, aspect, near, far);
+		shadow_transforms[0] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 1.0f,  0.0f,  0.0f)), v3f(0.0f, -1.0f,  0.0f))); /* right */
+		shadow_transforms[1] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f(-1.0f,  0.0f,  0.0f)), v3f(0.0f, -1.0f,  0.0f))); /* left */
+		shadow_transforms[2] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  1.0f,  0.0f)), v3f(0.0f,  0.0f,  1.0f))); /* top */
+		shadow_transforms[3] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f, -1.0f,  0.0f)), v3f(0.0f,  0.0f, -1.0f))); /* bottom */
+		shadow_transforms[4] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  0.0f,  1.0f)), v3f(0.0f, -1.0f,  0.0f))); /* near */
+		shadow_transforms[5] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  0.0f, -1.0f)), v3f(0.0f, -1.0f,  0.0f))); /* far */
+		glViewport(0, 0, shadow_width, shadow_height);
+		glBindFramebuffer(GL_FRAMEBUFFER, depth_cubemap_fbo);
+		glClear(GL_DEPTH_BUFFER_BIT);
+		glUseProgram(depth_shader);
+		shader_set_1f(depth_shader, "far", far);
+		shader_set_3fv(depth_shader, "light_pos", light_pos);
+		for (U32 i = 0; i < 6; ++i) {
+			char uniform_name[256];
+			snprintf(uniform_name, 256, "shadow_transforms[%d]", i);
+			shader_set_mat4fv(depth_shader, uniform_name, shadow_transforms[i]);
+		}
+		render_scene(depth_shader, cube);
+		glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+		/* NOTE(pryazha): Render the scene as normal */
+		glViewport(0, 0, screen_width, screen_height);
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+		glUseProgram(shadow_shader);
+
+		aspect = (F32)screen_width/(F32)screen_height;
+		proj = perspective(state.camera.fovx, aspect, state.camera.near, state.camera.far);
+		view = get_view_matrix(&state.camera);
+
+		shader_set_mat4fv(shadow_shader, "proj", proj); 
+		shader_set_mat4fv(shadow_shader, "view", view);
+		shader_set_3fv(shadow_shader, "light_pos", light_pos);
+		shader_set_3fv(shadow_shader, "view_pos", state.camera.pos);
+		shader_set_1f(shadow_shader, "far", far);
+
+		glActiveTexture(GL_TEXTURE0);
+		glBindTexture(GL_TEXTURE_2D, wood_texture);
+		glActiveTexture(GL_TEXTURE1);
+		glBindTexture(GL_TEXTURE_CUBE_MAP, depth_cubemap);
+		render_scene(shadow_shader, cube);
+
+		glfwSwapBuffers(window);
+
+		time = glfwGetTime();
+		state.dt = time-last_time;
+		last_time = time;
+	}
+
+	glfwTerminate();
+	return(0);
+
+error:
+	glfwTerminate();
+	return(1);
 }
diff --git a/advanced_lighting/3.2.point_shadows/shaders/depth.fs b/advanced_lighting/3.2.point_shadows/shaders/depth.frag
index 88fb9e6..f95c0f8 100644
--- a/advanced_lighting/3.2.point_shadows/shaders/depth.fs
+++ b/advanced_lighting/3.2.point_shadows/shaders/depth.frag
@@ -5,8 +5,7 @@ in vec4 frag_pos;
 uniform vec3 light_pos;
 uniform float far;
 
-void
-main(void)
+void main(void)
 {
     float light_distance = length(frag_pos.xyz-light_pos);
     light_distance = light_distance/far;
diff --git a/advanced_lighting/3.2.point_shadows/shaders/depth.gs b/advanced_lighting/3.2.point_shadows/shaders/depth.geom
index 638e2b9..de39788 100644
--- a/advanced_lighting/3.2.point_shadows/shaders/depth.gs
+++ b/advanced_lighting/3.2.point_shadows/shaders/depth.geom
@@ -6,18 +6,11 @@ uniform mat4 shadow_transforms[6];
 
 out vec4 frag_pos;
 
-void
-main(void)
+void main(void)
 {
-    for (int face = 0;
-         face < 6;
-         ++face)
-    {
+    for (int face = 0; face < 6; ++face) {
         gl_Layer = face;
-        for (int vertex = 0;
-             vertex < 3;
-             ++vertex)
-        {
+        for (int vertex = 0; vertex < 3; ++vertex) {
             frag_pos = gl_in[vertex].gl_Position;
             gl_Position = shadow_transforms[face]*frag_pos;
             EmitVertex();
diff --git a/advanced_lighting/3.2.point_shadows/shaders/depth.vs b/advanced_lighting/3.2.point_shadows/shaders/depth.vert
index 37a3484..37ffd1b 100644
--- a/advanced_lighting/3.2.point_shadows/shaders/depth.vs
+++ b/advanced_lighting/3.2.point_shadows/shaders/depth.vert
@@ -3,8 +3,7 @@ layout(location = 0) in vec3 apos;
 
 uniform mat4 model;
 
-void
-main(void)
+void main(void)
 {
     gl_Position = model*vec4(apos, 1.0);
 }
diff --git a/advanced_lighting/3.2.point_shadows/shaders/shadow.fs b/advanced_lighting/3.2.point_shadows/shaders/shadow.frag
index 6a3a8b0..bb006ca 100644
--- a/advanced_lighting/3.2.point_shadows/shaders/shadow.fs
+++ b/advanced_lighting/3.2.point_shadows/shaders/shadow.frag
@@ -24,8 +24,7 @@ vec3 grid_sampling_disk[20] = vec3[]
    vec3(0, 1,  1), vec3( 0, -1,  1), vec3( 0, -1, -1), vec3( 0, 1, -1)
 );
 
-float
-calculate_shadow(vec3 frag_pos)
+float calculate_shadow(vec3 frag_pos)
 {
     vec3 frag_to_light = frag_pos-light_pos;
     /* float closest_depth = texture(depth_cubemap, frag_to_light).r; */
@@ -80,8 +79,7 @@ calculate_shadow(vec3 frag_pos)
     return(shadow);
 }
 
-void
-main(void)
+void main(void)
 {
     vec3 color = texture(diffuse_texture, fs_in.tex_coords).rgb;
     vec3 normal = normalize(fs_in.normal);
diff --git a/advanced_lighting/3.2.point_shadows/shaders/shadow.vs b/advanced_lighting/3.2.point_shadows/shaders/shadow.vert
index ac8ee4f..dccaa76 100644
--- a/advanced_lighting/3.2.point_shadows/shaders/shadow.vs
+++ b/advanced_lighting/3.2.point_shadows/shaders/shadow.vert
@@ -9,14 +9,13 @@ out VS_OUT {
     vec2 tex_coords;
 } vs_out;
 
-uniform mat4 projection;
+uniform mat4 proj;
 uniform mat4 view;
 uniform mat4 model;
 
 uniform bool reverse_normals;
 
-void
-main(void)
+void main(void)
 {
     vs_out.frag_pos = vec3(model*vec4(apos, 1.0));
     if (reverse_normals)
@@ -25,5 +24,5 @@ main(void)
         vs_out.normal = mat3(transpose(inverse(model)))*anormal;
 
     vs_out.tex_coords = atex_coords;
-    gl_Position = projection*view*vec4(vs_out.frag_pos, 1.0);
+    gl_Position = proj*view*vec4(vs_out.frag_pos, 1.0);
 }
diff --git a/advanced_lighting/4.normal_mapping/normal_mapping b/advanced_lighting/4.normal_mapping/normal_mapping
index 6d33c26..1fbb26b 100755
--- a/advanced_lighting/4.normal_mapping/normal_mapping
+++ b/advanced_lighting/4.normal_mapping/normal_mapping
diff --git a/advanced_lighting/4.normal_mapping/normal_mapping.c b/advanced_lighting/4.normal_mapping/normal_mapping.c
index 1d65b49..980f4a0 100644
--- a/advanced_lighting/4.normal_mapping/normal_mapping.c
+++ b/advanced_lighting/4.normal_mapping/normal_mapping.c
@@ -1,288 +1,251 @@
-#include "pwyazh.h"
-
 #include "GL/glew.h"
 #include "GLFW/glfw3.h"
 
+#include "pwyazh.h"
 #include "pwyazh_GL.h"
 
 #include "common.h"
 
-static S32 global_screen_width = 800, global_screen_height = 600;
-static Input global_input;
-static B32 first_mouse = 1;
-
-void
-resize_callback(GLFWwindow* window, int width, int height)
-{
-    global_screen_width = width;
-    global_screen_height = height;
-    glViewport(0, 0, global_screen_width, global_screen_height);
-}
-
-void
-cursor_pos_callback(GLFWwindow* window, double xpos, double ypos)
-{
-    if (first_mouse)
-    {
-        global_input.last_mouse_pos = v2f(xpos, ypos);
-        first_mouse = 0;
-    }
-    global_input.mouse_offset = v2f(global_input.mouse_offset.x+((F32)xpos-global_input.last_mouse_pos.x),
-                                    global_input.mouse_offset.y+((F32)ypos-global_input.last_mouse_pos.y));
-    global_input.last_mouse_pos = v2f((F32)xpos, (F32)ypos);
-}
-
-void
-render_scene(U32 shader, Mesh *cube)
-{
-    MAT4 model;
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(5.0f, 5.0f, 5.0f));
-    shader_set_mat4fv(shader, "model", model);
-    glDisable(GL_CULL_FACE);
-    shader_set_1i(shader, "reverse_normals", 1);
-    mesh_draw(cube);
-    shader_set_1i(shader, "reverse_normals", 0);
-    glEnable(GL_CULL_FACE);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
-    model = mat4_translate(model, v3f(0.0f, 1.5f, 0.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.5f, 0.5f, 0.5f));
-    model = mat4_translate(model, v3f(2.0f, 0.0f, 1.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-
-    model = mat4_identity();
-    model = mat4_make_scale(v3f(0.25f, 0.25f, 0.25f));
-    model = mat4_rotate_angles(model, v3f(60.0f, 0.0f, 0.0f));
-    model = mat4_translate(model, v3f(-1.0f, 0.0f, 2.0f));
-    shader_set_mat4fv(shader, "model", model);
-    mesh_draw(cube);
-}
-
-int
-main(void)
+int main(void)
 {
-    GLFWwindow *window;
-    Arena *arena;
-    State state;
-    Mesh *cube;
-    F64 time, last_time;
-    V3F light_pos;
-    MAT4 shadow_transforms[6];
-    MAT4 proj, view;
-    
-    glfwSetErrorCallback(error_callback);
-    
-    if (glfwInit() == GLFW_FALSE)
-        return(1);
-    
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-    glfwWindowHint(GLFW_SAMPLES, 4);
-    window = glfwCreateWindow(global_screen_width, global_screen_height, "Point shadows", 0, 0);
-    if (!window)
-        goto error;
-
-    glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
-    
-    glfwSetWindowSizeCallback(window, resize_callback);
-    glfwSetCursorPosCallback(window, cursor_pos_callback);
-    
-    glfwMakeContextCurrent(window);
-    
-    if (glewInit() != GLEW_OK)
-        goto error;
-    
-    glEnable(GL_DEPTH_TEST);
-    glEnable(GL_CULL_FACE);
-    
-    /* NOTE(pryazha): Init */
-    arena = arena_alloc(Megabytes(64));
-    
-    state.camera = (Camera){
-        .pos = v3f(0.0f, 1.0f, 3.0f),
-        .fovx = 100.0f,
-        .near = 0.1f,
-        .far = 100.0f,
-        .yaw = 0.0f,
-        .pitch = 0.0f
-    };
-    V3F camera_dp = v3f_zero();
-    /* light_pos = v3f(-2.0f, 4.0f, -2.0f); */
-    light_pos = v3f_zero();
-
-    /* NOTE(pryazha): Meshes */
-    cube = mesh_load_obj(arena, "../../data/models/cube.obj");
-    
-    F32 quad_vertices[] = {
-        -1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
-         1.0f, -1.0f,  0.0f,   1.0f, 0.0f,
-         1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
-        -1.0f, -1.0f,  0.0f,   0.0f, 0.0f,
-         1.0f,  1.0f,  0.0f,   1.0f, 1.0f,
-        -1.0f,  1.0f,  0.0f,   0.0f, 1.0f
-    };
-    U32 quad_vao, vbo;
-    glGenVertexArrays(1, &quad_vao);
-    glBindVertexArray(quad_vao);
-    glGenBuffers(1, &vbo);
-    glBindBuffer(GL_ARRAY_BUFFER, vbo);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), quad_vertices, GL_STATIC_DRAW);
-    glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)0);
-    glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)(3*sizeof(F32)));
-    glBindVertexArray(0);
-
-    /* NOTE(pryazha): Shaders */
-    U32 depth_shader = create_shader_program_geom("shaders/depth.vs",
-                                                  "shaders/depth.fs",
-                                                  "shaders/depth.gs");
-    U32 shadow_shader = create_shader_program("shaders/shadow.vs", "shaders/shadow.fs");
-    
-    glUseProgram(shadow_shader);
-    shader_set_1i(shadow_shader, "diffuse_texture", 0);
-    shader_set_1i(shadow_shader, "depth_cubemap", 1);
-    glUseProgram(0);
-
-    U32 wood_texture = load_texture_gamma("../../data/textures/wood.png", 0);
-
-    /* NOTE(pryazha): Depth framebuffer init */
-    U32 depth_cubemap_fbo, depth_cubemap;
-    U32 shadow_width = 1024, shadow_height = 1024;
-    glGenFramebuffers(1, &depth_cubemap_fbo);
-    glGenTextures(1, &depth_cubemap);
-    glBindTexture(GL_TEXTURE_CUBE_MAP, depth_cubemap);
-    for (U32 cubemap_side = 0; cubemap_side < 6; ++cubemap_side)
-        glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X+cubemap_side, 0, GL_DEPTH_COMPONENT,
-                     shadow_width, shadow_height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
-    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_BORDER);
-    glBindFramebuffer(GL_FRAMEBUFFER, depth_cubemap_fbo);
-    glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depth_cubemap, 0);
-    glDrawBuffer(GL_NONE);
-    glReadBuffer(GL_NONE);
-    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
-        fprintf(stderr, "[ERROR]: Failed to complete depth map framebuffer.\n");
-    glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-    last_time = glfwGetTime();
-    
-    while (!glfwWindowShouldClose(window))
-    {
-        glfwPollEvents();
-
-        /* NOTE(pryazha): For now it's easier to write all of the logic in the main loop */
-
-        /* NOTE(pryazha): Update */
-        process_glfw_keyboard(window, &global_input);
-
-        if (key_first_press(global_input.exit))
-            glfwSetWindowShouldClose(window, GLFW_TRUE);
-
-        F32 x, y, z, angular_speed, radius;
-        V3F camera_dv;
-
-        camera_dv = get_dv_camera_first_person(&global_input, &state.camera,
-                                               1.0f, state.dt);
-        if (key_is_pressed(global_input.action_up))
-            camera_dv = v3f_scalef(camera_dv, 3.0f);
-        camera_dp = v3f_add(camera_dp, camera_dv);
-        camera_dp = v3f_scalef(camera_dp, 0.8f);
-        state.camera.pos = v3f_add(state.camera.pos, camera_dp);
-
-        F32 sensitivity = 0.1f;
-        global_input.mouse_offset = v2f_scalef(global_input.mouse_offset, sensitivity);
-        state.camera.yaw += global_input.mouse_offset.x;
-        state.camera.pitch += global_input.mouse_offset.y;
-        if (state.camera.pitch > 89.0f)
-            state.camera.pitch = 89.0f;
-        if (state.camera.pitch < -89.0f)
-            state.camera.pitch = -89.0f;
-
-        input_update_last_state(&global_input);
-
-        angular_speed = 1.0f;
-        radius = 4.0f;
-        x = f32_sin(time*angular_speed)*radius;
-        y = f32_sin(time*angular_speed)*radius;
-        z = f32_cos(time*angular_speed)*radius;
-
-        light_pos = v3f(x, y, z);
-
-        /* NOTE(pryazha): Render */
-
-        /* NOTE(pryazha): Render the depth cubemap */
-        F32 fovx, aspect, near, far;
-        fovx = 90.0f;
-        aspect = (F32)shadow_width/(F32)shadow_height;
-        near = 1.0f;
-        far = 25.0f;
-        proj = perspective(fovx, aspect, near, far);
-        shadow_transforms[0] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 1.0f,  0.0f,  0.0f)), v3f(0.0f, -1.0f,  0.0f))); /* right */
-        shadow_transforms[1] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f(-1.0f,  0.0f,  0.0f)), v3f(0.0f, -1.0f,  0.0f))); /* left */
-        shadow_transforms[2] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  1.0f,  0.0f)), v3f(0.0f,  0.0f,  1.0f))); /* top */
-        shadow_transforms[3] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f, -1.0f,  0.0f)), v3f(0.0f,  0.0f, -1.0f))); /* bottom */
-        shadow_transforms[4] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  0.0f,  1.0f)), v3f(0.0f, -1.0f,  0.0f))); /* near */
-        shadow_transforms[5] = mat4_mul(proj, look_at(light_pos, v3f_add(light_pos, v3f( 0.0f,  0.0f, -1.0f)), v3f(0.0f, -1.0f,  0.0f))); /* far */
-        glViewport(0, 0, shadow_width, shadow_height);
-        glBindFramebuffer(GL_FRAMEBUFFER, depth_cubemap_fbo);
-        glClear(GL_DEPTH_BUFFER_BIT);
-        glUseProgram(depth_shader);
-        shader_set_1f(depth_shader, "far", far);
-        shader_set_3fv(depth_shader, "light_pos", light_pos);
-        for (U32 i = 0; i < 6; ++i)
-        {
-            char uniform_name[256];
-            snprintf(uniform_name, 256, "shadow_transforms[%d]", i);
-            shader_set_mat4fv(depth_shader, uniform_name, shadow_transforms[i]);
-        }
-        render_scene(depth_shader, cube);
-        glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-        /* NOTE(pryazha): Render the scene as normal */
-        glViewport(0, 0, global_screen_width, global_screen_height);
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
-        glUseProgram(shadow_shader);
-
-        aspect = (F32)global_screen_width/(F32)global_screen_height;
-        proj = perspective(state.camera.fovx, aspect, state.camera.near, state.camera.far);
-        view = get_view_matrix(&state.camera);
-
-        shader_set_mat4fv(shadow_shader, "projection", proj); 
-        shader_set_mat4fv(shadow_shader, "view", view);
-        shader_set_3fv(shadow_shader, "light_pos", light_pos);
-        shader_set_3fv(shadow_shader, "view_pos", state.camera.pos);
-        shader_set_1f(shadow_shader, "far", far);
-
-        glActiveTexture(GL_TEXTURE0);
-        glBindTexture(GL_TEXTURE_2D, wood_texture);
-        glActiveTexture(GL_TEXTURE1);
-        glBindTexture(GL_TEXTURE_CUBE_MAP, depth_cubemap);
-        render_scene(shadow_shader, cube);
-
-        glfwSwapBuffers(window);
-        
-        time = glfwGetTime();
-        state.dt = time-last_time;
-        last_time = time;
-    }
-
-    glfwTerminate();
-    return(0);
-    
-    error:
-    glfwTerminate();
-    return(1);
+	GLFWwindow *window;
+	State state;
+	Input input;
+	F64 time, last_time;
+	V3F light_pos;
+	MAT4 proj, view, model;
+	F32 aspect, angle = 0.0f;
+	Mesh *cube = 0;
+	Arena *arena = 0;
+	S32 width, height;
+
+	glfwSetErrorCallback(error_callback);
+
+	if (glfwInit() == GLFW_FALSE)
+		return(1);
+
+	width = 800;
+	height = 600;
+
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+	glfwWindowHint(GLFW_SAMPLES, 4);
+	window = glfwCreateWindow(width, height, "Point shadows", 0, 0);
+	if (!window)
+		goto error;
+
+	glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
+
+	glfwMakeContextCurrent(window);
+
+	if (glewInit() != GLEW_OK)
+		goto error;
+
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_CULL_FACE);
+
+	/* NOTE(pryazha): Init */
+	arena = arena_alloc(Kilobytes(4));
+
+	state.camera = (Camera){ v3f(0.0f, 1.0f, 3.0f), 100.0f, 0.1f, 100.0f, 0.0f, 0.0f };
+	V3F camera_dp = v3f_zero();
+	F32 x, y, z;
+
+	/* NOTE(pryazha): Meshes */
+	cube = mesh_load_obj(arena, "../../data/models/cube.obj");
+
+	/* Positions */
+	V3F p1 = v3f(-1.0f, 1.0f, 0.0f);
+	V3F p2 = v3f(-1.0f, -1.0f, 0.0f);
+	V3F p3 = v3f(1.0f, -1.0f, 0.0f);
+	V3F p4 = v3f(1.0f, 1.0f, 0.0f);
+	/* Texture ccoordinates */
+	V2F uv1 = v2f(0.0f, 1.0f);
+	V2F uv2 = v2f(0.0f, 0.0f);
+	V2F uv3 = v2f(1.0f, 0.0f);
+	V2F uv4 = v2f(1.0f, 1.0f);
+	/* Normal vector */
+	V3F nm = v3f(0.0f, 0.0f, 1.0f);
+
+	V3F edge1, edge2;
+	V2F duv1, duv2;
+	F32 f;
+	V3F t1, bit1, t2, bit2;
+
+	edge1 = v3f_sub(p2, p1);
+	edge2 = v3f_sub(p3, p1);
+	duv1 = v2f_sub(uv2, uv1);
+	duv2 = v2f_sub(uv3, uv1);
+
+	f = 1.0f/(duv1.x*duv2.y-duv2.x*duv1.y);
+
+	t1.x = f*(duv2.y*edge1.x-duv1.y*edge2.x);
+	t1.y = f*(duv2.y*edge1.y-duv1.y*edge2.y);
+	t1.z = f*(duv2.y*edge1.z-duv1.y*edge2.z);
+
+	bit1.x = f*(-duv2.x*edge1.x+duv1.x*edge2.x);
+	bit1.y = f*(-duv2.x*edge1.y+duv1.x*edge2.y);
+	bit1.z = f*(-duv2.x*edge1.z+duv1.x*edge2.z);
+
+	edge1 = v3f_sub(p3, p1);
+	edge2 = v3f_sub(p4, p1);
+	duv1 = v2f_sub(uv3, uv1);
+	duv2 = v2f_sub(uv4, uv1);
+
+	f = 1.0f/(duv1.x*duv2.y-duv2.x*duv1.y);
+
+	t2.x = f*(duv2.y*edge1.x-duv1.y*edge2.x);
+	t2.y = f*(duv2.y*edge1.y-duv1.y*edge2.y);
+	t2.z = f*(duv2.y*edge1.z-duv1.y*edge2.z);
+
+	bit2.x = f*(-duv2.x*edge1.x+duv1.x*edge2.x);
+	bit2.y = f*(-duv2.x*edge1.y+duv1.x*edge2.y);
+	bit2.z = f*(-duv2.x*edge1.z+duv1.x*edge2.z);
+
+	F32 quad_vertices[] = {
+		p1.x, p1.y, p1.z, nm.x, nm.y, nm.z, uv1.x, uv1.y, t1.x, t1.y, t1.z, bit1.x, bit1.y, bit1.z,
+		p2.x, p2.y, p2.z, nm.x, nm.y, nm.z, uv2.x, uv2.y, t1.x, t1.y, t1.z, bit1.x, bit1.y, bit1.z,
+		p3.x, p3.y, p3.z, nm.x, nm.y, nm.z, uv3.x, uv3.y, t1.x, t1.y, t1.z, bit1.x, bit1.y, bit1.z,
+
+		p1.x, p1.y, p1.z, nm.x, nm.y, nm.z, uv1.x, uv1.y, t2.x, t2.y, t2.z, bit2.x, bit2.y, bit2.z,
+		p3.x, p3.y, p3.z, nm.x, nm.y, nm.z, uv3.x, uv3.y, t2.x, t2.y, t2.z, bit2.x, bit2.y, bit2.z,
+		p4.x, p4.y, p4.z, nm.x, nm.y, nm.z, uv4.x, uv4.y, t2.x, t2.y, t2.z, bit2.x, bit2.y, bit2.z
+	};
+	U32 quad_vao, vbo;
+	glGenVertexArrays(1, &quad_vao);
+	glBindVertexArray(quad_vao);
+	glGenBuffers(1, &vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(quad_vertices), quad_vertices, GL_STATIC_DRAW);
+	glEnableVertexAttribArray(0);
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 14*sizeof(F32), (void *)0);
+	glEnableVertexAttribArray(1);
+	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 14*sizeof(F32), (void *)(3*sizeof(F32)));
+	glEnableVertexAttribArray(2);
+	glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 14*sizeof(F32), (void *)(6*sizeof(F32)));
+	glEnableVertexAttribArray(3);
+	glVertexAttribPointer(3, 3, GL_FLOAT, GL_FALSE, 14*sizeof(F32), (void *)(8*sizeof(F32)));
+	glEnableVertexAttribArray(4);
+	glVertexAttribPointer(4, 3, GL_FLOAT, GL_FALSE, 14*sizeof(F32), (void *)(11*sizeof(F32)));
+	glBindVertexArray(0);
+
+	/* NOTE(pryazha): Shaders */
+	U32 normal_map_shader = create_shader_program("shaders/normal_map.vert",
+						      "shaders/normal_map.frag");
+	U32 normals_debug_shader = create_shader_program_geom("shaders/normals_debug.vert",
+							      "shaders/normals_debug.frag",
+							      "shaders/normals_debug.geom");
+	U32 color_shader = create_shader_program("shaders/color.vert",
+						 "shaders/color.frag");
+
+	glUseProgram(normal_map_shader);
+	shader_set_1i(normal_map_shader, "diffuse_texture", 0);
+	shader_set_1i(normal_map_shader, "normal_map", 1);
+	glUseProgram(0);
+
+	U32 brickwall_diffuse_texture = load_texture("../../data/textures/brickwall.jpg");
+	U32 brickwall_normal_texture = load_texture("../../data/textures/brickwall_normal.jpg");
+
+	last_time = glfwGetTime();
+
+	while (!glfwWindowShouldClose(window)) {
+		glfwPollEvents();
+
+		/* NOTE(pryazha): For now it's easier to write all of the logic in the main loop */
+
+		/* NOTE(pryazha): Update */
+		glfwGetFramebufferSize(window, &width, &height);
+		process_glfw_keyboard(window, &input);
+		process_glfw_mouse_pos(window, &input);
+
+		if (key_first_press(input.exit))
+			glfwSetWindowShouldClose(window, GLFW_TRUE);
+
+		F32 speed = 2.0f;
+		V3F dv = get_dv_camera_first_person(&input, &state.camera,
+						    speed, state.dt);
+		if (key_is_pressed(input.action_up))
+			dv = v3f_scalef(dv, 3.0f);
+		camera_dp = v3f_add(camera_dp, dv);
+		camera_dp = v3f_scalef(camera_dp, 0.8f);
+		state.camera.pos = v3f_add(state.camera.pos, camera_dp);
+
+		F32 sensitivity = 0.1f;
+		input.mouse_offset = v2f_scalef(input.mouse_offset, sensitivity);
+		state.camera.yaw += input.mouse_offset.x;
+		state.camera.pitch += input.mouse_offset.y;
+		if (state.camera.pitch > 89.0f)
+			state.camera.pitch = 89.0f;
+		if (state.camera.pitch < -89.0f)
+			state.camera.pitch = -89.0f;
+
+		input_update_last_state(&input);
+
+		angle += 40.0f*state.dt;
+
+		x = f32_cos((F32)time);
+		y = f32_sin((F32)time);
+		z = 1.0f;
+		light_pos = v3f(x, y, z);
+
+		/* NOTE(pryazha): Render */
+		aspect = (F32)width/(F32)height;
+		proj = perspective(state.camera.fovx, aspect,
+				   state.camera.near, state.camera.far);
+		view = get_view_matrix(&state.camera);
+
+		glViewport(0, 0, width, height);
+		glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+		glUseProgram(normal_map_shader);
+		shader_set_mat4fv(normal_map_shader, "proj", proj); 
+		shader_set_mat4fv(normal_map_shader, "view", view);
+		shader_set_3fv(normal_map_shader, "light_pos", light_pos);
+		shader_set_3fv(normal_map_shader, "view_pos", state.camera.pos);
+		model = mat4_rotate_angles(mat4_identity(), v3f(angle, angle, angle));
+		shader_set_mat4fv(normal_map_shader, "model", model);
+		glActiveTexture(GL_TEXTURE0);
+		glBindTexture(GL_TEXTURE_2D, brickwall_diffuse_texture);
+		glActiveTexture(GL_TEXTURE1);
+		glBindTexture(GL_TEXTURE_2D, brickwall_normal_texture);
+		glBindVertexArray(quad_vao);
+		glDrawArrays(GL_TRIANGLES, 0, 6);
+		glBindVertexArray(0);
+		glUseProgram(0);
+
+		glUseProgram(color_shader);
+		shader_set_mat4fv(color_shader, "proj", proj); 
+		shader_set_mat4fv(color_shader, "view", view);
+		model = mat4_make_scale(v3f(0.05f, 0.05f, 0.05f));
+		model = mat4_translate(model, light_pos);
+		shader_set_mat4fv(color_shader, "model", model);
+		mesh_draw(cube);
+		glUseProgram(0);
+
+		glUseProgram(normals_debug_shader);
+		shader_set_mat4fv(normals_debug_shader, "proj", proj); 
+		shader_set_mat4fv(normals_debug_shader, "view", view);
+		model = mat4_rotate_angles(mat4_identity(), v3f(angle, angle, angle));
+		shader_set_mat4fv(normals_debug_shader, "model", model);
+		glBindVertexArray(quad_vao);
+		glDrawArrays(GL_TRIANGLES, 0, 6);
+		glBindVertexArray(0);
+		glUseProgram(0);
+
+		glfwSwapBuffers(window);
+
+		time = glfwGetTime();
+		state.dt = time-last_time;
+		last_time = time;
+	}
+
+	arena_release(arena);
+	glfwTerminate();
+	return(0);
+
+error:
+	arena_release(arena);
+	glfwTerminate();
+	return(1);
 }
diff --git a/advanced_lighting/4.normal_mapping/shaders/color.frag b/advanced_lighting/4.normal_mapping/shaders/color.frag
new file mode 100644
index 0000000..c01da99
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/color.frag
@@ -0,0 +1,8 @@
+#version 330 core
+
+out vec4 frag_color;
+
+void main(void)
+{
+    frag_color = vec4(1.0);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/color.vert b/advanced_lighting/4.normal_mapping/shaders/color.vert
new file mode 100644
index 0000000..a8b1247
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/color.vert
@@ -0,0 +1,11 @@
+#version 330 core
+layout(location = 0) in vec3 apos;
+
+uniform mat4 proj;
+uniform mat4 view;
+uniform mat4 model;
+
+void main(void)
+{
+    gl_Position = proj*view*model*vec4(apos, 1.0);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/depth.fs b/advanced_lighting/4.normal_mapping/shaders/depth.fs
deleted file mode 100644
index 88fb9e6..0000000
--- a/advanced_lighting/4.normal_mapping/shaders/depth.fs
+++ /dev/null
@@ -1,14 +0,0 @@
-#version 330 core
-
-in vec4 frag_pos;
-
-uniform vec3 light_pos;
-uniform float far;
-
-void
-main(void)
-{
-    float light_distance = length(frag_pos.xyz-light_pos);
-    light_distance = light_distance/far;
-    gl_FragDepth = light_distance;
-}
diff --git a/advanced_lighting/4.normal_mapping/shaders/depth.gs b/advanced_lighting/4.normal_mapping/shaders/depth.gs
deleted file mode 100644
index 638e2b9..0000000
--- a/advanced_lighting/4.normal_mapping/shaders/depth.gs
+++ /dev/null
@@ -1,27 +0,0 @@
-#version 330 core
-layout(triangles) in;
-layout(triangle_strip, max_vertices=18) out;
-
-uniform mat4 shadow_transforms[6];
-
-out vec4 frag_pos;
-
-void
-main(void)
-{
-    for (int face = 0;
-         face < 6;
-         ++face)
-    {
-        gl_Layer = face;
-        for (int vertex = 0;
-             vertex < 3;
-             ++vertex)
-        {
-            frag_pos = gl_in[vertex].gl_Position;
-            gl_Position = shadow_transforms[face]*frag_pos;
-            EmitVertex();
-        }
-        EndPrimitive();
-    }
-}
diff --git a/advanced_lighting/4.normal_mapping/shaders/depth.vs b/advanced_lighting/4.normal_mapping/shaders/depth.vs
deleted file mode 100644
index 37a3484..0000000
--- a/advanced_lighting/4.normal_mapping/shaders/depth.vs
+++ /dev/null
@@ -1,10 +0,0 @@
-#version 330 core
-layout(location = 0) in vec3 apos;
-
-uniform mat4 model;
-
-void
-main(void)
-{
-    gl_Position = model*vec4(apos, 1.0);
-}
diff --git a/advanced_lighting/4.normal_mapping/shaders/normal_map.frag b/advanced_lighting/4.normal_mapping/shaders/normal_map.frag
new file mode 100644
index 0000000..964d6f8
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/normal_map.frag
@@ -0,0 +1,51 @@
+#version 330 core
+
+in VS_OUT {
+    /* mat3 TBN; */
+    vec3 frag_pos;
+    vec3 tangent_light_pos;
+    vec3 tangent_view_pos;
+    vec3 tangent_frag_pos;
+    vec2 tex_coords;
+} fs_in;
+
+out vec4 frag_color;
+
+/* uniform vec3 light_pos; */
+/* uniform vec3 view_pos; */
+
+uniform sampler2D diffuse_texture;
+uniform sampler2D normal_map;
+
+void main(void)
+{
+    vec3 color = vec3(texture(diffuse_texture, fs_in.tex_coords));
+    vec3 normal = vec3(texture(normal_map, fs_in.tex_coords));
+    normal = normalize((normal*2.0)-1.0);
+    /*
+    normal = normalize(fs_in.TBN*normal);
+
+    vec3 light_dir = fs_in.TBN * normalize(light_pos - fs_in.frag_pos);
+    vec3 view_dir = fs_in.TBN * normalize(view_pos - fs_in.frag_pos);
+    */
+
+    vec3 light_color = vec3(1.0);
+
+    float ambient = 0.01;
+
+    /* vec3 light_dir = normalize(light_pos-fs_in.frag_pos); */
+    vec3 light_dir = normalize(fs_in.tangent_light_pos - fs_in.tangent_frag_pos);
+    float diff = max(dot(light_dir, normal), 0.0);
+    vec3 diffuse = diff*light_color;
+
+    /* vec3 view_dir = normalize(view_pos-fs_in.frag_pos); */
+    vec3 view_dir = normalize(fs_in.tangent_view_pos-fs_in.frag_pos);
+    vec3 halfway_dir = normalize(light_dir+view_dir); 
+    float spec = pow(max(dot(halfway_dir, normal), 0.0), 64.0);
+    float spec_strength = 1.0;
+    vec3 specular = spec_strength*spec*light_color;
+
+    vec3 result = (ambient+diffuse+specular)*color;
+
+    frag_color = vec4(result, 1.0);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/normal_map.vert b/advanced_lighting/4.normal_mapping/shaders/normal_map.vert
new file mode 100644
index 0000000..3b089b5
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/normal_map.vert
@@ -0,0 +1,36 @@
+#version 330 core
+layout(location = 0) in vec3 apos;
+layout(location = 1) in vec3 anormal;
+layout(location = 2) in vec2 atex_coords;
+layout(location = 3) in vec3 atangent;
+layout(location = 4) in vec3 abitangent;
+
+out VS_OUT {
+    /* mat3 TBN; */
+    vec3 frag_pos;
+    vec3 tangent_light_pos;
+    vec3 tangent_view_pos;
+    vec3 tangent_frag_pos;
+    vec2 tex_coords;
+} vs_out;
+
+uniform mat4 proj;
+uniform mat4 view;
+uniform mat4 model;
+
+uniform vec3 light_pos;
+uniform vec3 view_pos;
+
+void main(void)
+{
+    vs_out.frag_pos = vec3(model * vec4(apos, 1.0));
+    vs_out.tex_coords = atex_coords;
+    vec3 T = normalize(vec3(model * vec4(atangent, 0.0)));
+    vec3 B = normalize(vec3(model * vec4(abitangent, 0.0)));
+    vec3 N = normalize(vec3(model * vec4(anormal, 0.0)));
+    mat3 TBN = transpose(mat3(T, B, N));
+    vs_out.tangent_light_pos = TBN * light_pos;
+    vs_out.tangent_view_pos = TBN * view_pos;
+    vs_out.tangent_frag_pos = TBN * vec3(model * vec4(apos, 0.0));
+    gl_Position = proj * view * vec4(vs_out.frag_pos, 1.0);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/normals_debug.frag b/advanced_lighting/4.normal_mapping/shaders/normals_debug.frag
new file mode 100644
index 0000000..04dadd4
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/normals_debug.frag
@@ -0,0 +1,10 @@
+#version 330 core
+
+in vec3 vcolor;
+
+out vec4 frag_color;
+
+void main(void)
+{
+    frag_color = vec4(vcolor, 1.0);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/normals_debug.geom b/advanced_lighting/4.normal_mapping/shaders/normals_debug.geom
new file mode 100644
index 0000000..666c08a
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/normals_debug.geom
@@ -0,0 +1,44 @@
+#version 330 core
+layout(triangles) in;
+layout(line_strip, max_vertices=18) out;
+
+in VS_OUT {
+    vec4 tangent;
+    vec4 bitangent;
+    vec4 normal;
+} gs_in[];
+
+out vec3 vcolor;
+
+uniform mat4 proj;
+
+void gen_normals(int index)
+{
+    vcolor = vec3(1.0, 0.0, 0.0);
+    gl_Position = proj*(gl_in[index].gl_Position);
+    EmitVertex();
+    gl_Position = proj*(gl_in[index].gl_Position+0.5*gs_in[index].tangent);
+    EmitVertex();
+    EndPrimitive();
+
+    vcolor = vec3(0.0, 0.0, 1.0);
+    gl_Position = proj*(gl_in[index].gl_Position);
+    EmitVertex();
+    gl_Position = proj*(gl_in[index].gl_Position+0.5*gs_in[index].bitangent);
+    EmitVertex();
+    EndPrimitive();
+
+    vcolor = vec3(0.0, 1.0, 0.0);
+    gl_Position = proj*(gl_in[index].gl_Position);
+    EmitVertex();
+    gl_Position = proj*(gl_in[index].gl_Position+0.5*gs_in[index].normal);
+    EmitVertex();
+    EndPrimitive();
+}
+
+void main(void)
+{
+    gen_normals(0);
+    gen_normals(1);
+    gen_normals(2);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/normals_debug.vert b/advanced_lighting/4.normal_mapping/shaders/normals_debug.vert
new file mode 100644
index 0000000..d3eed77
--- /dev/null
+++ b/advanced_lighting/4.normal_mapping/shaders/normals_debug.vert
@@ -0,0 +1,22 @@
+#version 330 core
+layout(location = 0) in vec3 apos;
+layout(location = 1) in vec3 anormal;
+layout(location = 3) in vec3 atangent;
+layout(location = 4) in vec3 abitangent;
+
+out VS_OUT {
+    vec4 tangent;
+    vec4 bitangent;
+    vec4 normal;
+} vs_out;
+
+uniform mat4 view;
+uniform mat4 model;
+
+void main(void)
+{
+    vs_out.tangent = view*model*vec4(normalize(atangent), 0.0);
+    vs_out.bitangent = view*model*vec4(normalize(abitangent), 0.0);
+    vs_out.normal = view*model*vec4(normalize(anormal), 0.0);
+    gl_Position = view*model*vec4(apos, 1.0);
+}
diff --git a/advanced_lighting/4.normal_mapping/shaders/shadow.fs b/advanced_lighting/4.normal_mapping/shaders/shadow.fs
deleted file mode 100644
index 6a3a8b0..0000000
--- a/advanced_lighting/4.normal_mapping/shaders/shadow.fs
+++ /dev/null
@@ -1,105 +0,0 @@
-#version 330 core
-
-in VS_OUT {
-    vec3 frag_pos;
-    vec3 normal;
-    vec2 tex_coords;
-} fs_in;
-
-out vec4 frag_color;
-
-uniform vec3 light_pos;
-uniform vec3 view_pos;
-uniform float far;
-
-uniform sampler2D diffuse_texture;
-uniform samplerCube depth_cubemap;
-
-vec3 grid_sampling_disk[20] = vec3[]
-(
-   vec3(1, 1,  1), vec3( 1, -1,  1), vec3(-1, -1,  1), vec3(-1, 1,  1), 
-   vec3(1, 1, -1), vec3( 1, -1, -1), vec3(-1, -1, -1), vec3(-1, 1, -1),
-   vec3(1, 1,  0), vec3( 1, -1,  0), vec3(-1, -1,  0), vec3(-1, 1,  0),
-   vec3(1, 0,  1), vec3(-1,  0,  1), vec3( 1,  0, -1), vec3(-1, 0, -1),
-   vec3(0, 1,  1), vec3( 0, -1,  1), vec3( 0, -1, -1), vec3( 0, 1, -1)
-);
-
-float
-calculate_shadow(vec3 frag_pos)
-{
-    vec3 frag_to_light = frag_pos-light_pos;
-    /* float closest_depth = texture(depth_cubemap, frag_to_light).r; */
-    /* closest_depth *= far; */
-    float current_depth = length(frag_to_light);
-    /* float bias = 0.05; */
-    /* float shadow = current_depth-bias > closest_depth ? 1.0 : 0.0; */
-    /* NOTE(pryazha): Display depth value for debugging */
-    /* frag_color = vec4(vec3(closest_depth/far), 1.0); */
-    /*
-    float shadow = 0.0;
-    float offset = 0.1;
-    float samples = 4.0;
-    for (float x = -offset;
-         x < offset;
-         x += offset/(samples*0.5))
-    {
-        for (float y = -offset;
-             y < offset;
-             y += offset/(samples*0.5))
-        {
-            for (float z = -offset;
-                 z < offset;
-                 z += offset/(samples*0.5))
-            {
-                float closest_depth = texture(depth_cubemap, frag_to_light+vec3(x, y, z)).r;
-                closest_depth *= far;
-                if (current_depth-bias > closest_depth)
-                    shadow += 1.0;
-            }
-        }
-    }
-    shadow /= (samples*samples*samples);
-    */
-
-    float shadow = 0.0;
-    float bias = 0.15;
-    int samples = 20;
-    float view_distance = length(view_pos-frag_pos);
-    float disk_radius = (1.0+(view_distance/far))/25.0;
-    for (int sample = 0;
-         sample < samples;
-         ++sample)
-    {
-        float closest_depth = texture(depth_cubemap, frag_to_light+
-                                      grid_sampling_disk[sample]*disk_radius).r;
-        closest_depth *= far;
-        if (current_depth-bias > closest_depth)
-            shadow += 1.0;
-    }
-    shadow /= float(samples);
-    return(shadow);
-}
-
-void
-main(void)
-{
-    vec3 color = texture(diffuse_texture, fs_in.tex_coords).rgb;
-    vec3 normal = normalize(fs_in.normal);
-    vec3 light_color = vec3(0.5);
-
-    vec3 ambient = 0.5*light_color;
-    
-    vec3 light_dir = normalize(light_pos-fs_in.frag_pos);
-    float diff = max(dot(light_dir, normal), 0.0);
-    vec3 diffuse = diff*light_color;
-
-    vec3 view_dir = normalize(view_pos-fs_in.frag_pos);
-    vec3 halfway_dir = normalize(light_dir+view_dir); 
-    float spec = pow(max(dot(halfway_dir, normal), 0.0), 64.0);
-    vec3 specular = spec*light_color;
-
-    float shadow = calculate_shadow(fs_in.frag_pos);
-    vec3 lighting = (ambient+(1.0-shadow)*(diffuse+specular))*color;
-
-    frag_color = vec4(lighting, 1.0);
-}
diff --git a/advanced_lighting/4.normal_mapping/shaders/shadow.vs b/advanced_lighting/4.normal_mapping/shaders/shadow.vs
deleted file mode 100644
index ac8ee4f..0000000
--- a/advanced_lighting/4.normal_mapping/shaders/shadow.vs
+++ /dev/null
@@ -1,29 +0,0 @@
-#version 330 core
-layout(location = 0) in vec3 apos;
-layout(location = 1) in vec3 anormal;
-layout(location = 2) in vec2 atex_coords;
-
-out VS_OUT {
-    vec3 frag_pos;
-    vec3 normal;
-    vec2 tex_coords;
-} vs_out;
-
-uniform mat4 projection;
-uniform mat4 view;
-uniform mat4 model;
-
-uniform bool reverse_normals;
-
-void
-main(void)
-{
-    vs_out.frag_pos = vec3(model*vec4(apos, 1.0));
-    if (reverse_normals)
-        vs_out.normal = mat3(transpose(inverse(model)))*(-1.0*anormal);
-    else
-        vs_out.normal = mat3(transpose(inverse(model)))*anormal;
-
-    vs_out.tex_coords = atex_coords;
-    gl_Position = projection*view*vec4(vs_out.frag_pos, 1.0);
-}