initial commit

1 files changed, 422 insertions, 0 deletions

diff --git a/framebuffers/framebuffers.c b/framebuffers/framebuffers.c
new file mode 100644
index 0000000..e71c95c
--- /dev/null
+++ b/framebuffers/framebuffers.c
@@ -0,0 +1,422 @@
+#include "GL/glew.h"
+#include "GLFW/glfw3.h"
+
+#include "pwyazh.h"
+
+#include "common.h"
+
+#include <unistd.h>
+
+#define WIDTH 1024
+#define HEIGHT 768
+
+static V3F camera_pos;
+static F32 dt;
+static Input input;
+
+void
+key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
+{
+    switch (action)
+    {
+        case GLFW_PRESS: {
+            switch (key)
+            {
+                case GLFW_KEY_D: {
+                    input.move_right.state = KeyState_PRESS;
+                } break;
+                case GLFW_KEY_W: {
+                    input.move_forward.state = KeyState_PRESS;
+                } break;
+                case GLFW_KEY_A: {
+                    input.move_left.state = KeyState_PRESS;
+                } break;
+                case GLFW_KEY_S: {
+                    input.move_backward.state = KeyState_PRESS;
+                } break;
+                case GLFW_KEY_E: {
+                    input.move_up.state = KeyState_PRESS;
+                } break;
+                case GLFW_KEY_Q: {
+                    input.move_down.state = KeyState_PRESS;
+                } break;
+            }
+        } break;
+
+        case GLFW_RELEASE: {
+            switch (key)
+            {
+                case GLFW_KEY_D: {
+                    input.move_right.state = KeyState_RELEASE;
+                } break;
+                case GLFW_KEY_W: {
+                    input.move_forward.state = KeyState_RELEASE;
+                } break;
+                case GLFW_KEY_A: {
+                    input.move_left.state = KeyState_RELEASE;
+                } break;
+                case GLFW_KEY_S: {
+                    input.move_backward.state = KeyState_RELEASE;
+                } break;
+                case GLFW_KEY_E: {
+                    input.move_up.state = KeyState_RELEASE;
+                } break;
+                case GLFW_KEY_Q: {
+                    input.move_down.state = KeyState_RELEASE;
+                } break;
+            }
+        } break;
+    }
+}
+
+int
+main(void)
+{
+    GLFWwindow *window;
+    
+    if (glfwInit() == GLFW_FALSE)
+    {
+        fprintf(stderr, "[ERROR] Failed to initialize glfw.\n");
+        return(1);
+    }
+    
+    glfwWindowHint(GLFW_RESIZABLE, 0);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
+    window = glfwCreateWindow(WIDTH, HEIGHT, "depth testing", 0, 0);
+    if (!window)
+    {
+        fprintf(stderr, "[ERROR] Failed to create window.\n");
+        glfwTerminate();
+        return(1);
+    }
+    
+    glfwMakeContextCurrent(window);
+    
+    glfwSetKeyCallback(window, key_callback);
+    
+    if (glewInit() != GLEW_OK)
+    {
+        fprintf(stderr, "[ERROR] Failed to initialize glew.\n");
+        glfwTerminate();
+        return(1);
+    }
+    
+    U32 screen_shader = create_shader_program("shaders/screen.vs", "shaders/screen.fs");
+    U32 cube_shader = create_shader_program("shaders/cube.vs", "shaders/cube.fs");
+    U32 marble_texture = load_texture("../data/textures/marble.jpg");
+    U32 metal_texture = load_texture("../data/textures/metal.png");
+    U32 window_texture = load_texture("../data/textures/window.png");
+
+    U32 fbo;
+    glGenFramebuffers(1, &fbo);
+    glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+
+    U32 texture_colorbuffer;
+    glGenTextures(1, &texture_colorbuffer);
+    glBindTexture(GL_TEXTURE_2D, texture_colorbuffer);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, WIDTH, HEIGHT, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
+                           texture_colorbuffer, 0);
+
+    U32 rbo;
+    glGenRenderbuffers(1, &rbo);
+    glBindRenderbuffer(GL_RENDERBUFFER, rbo);
+    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, WIDTH, HEIGHT);
+    glBindRenderbuffer(GL_RENDERBUFFER, 0);
+
+    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
+                              GL_RENDERBUFFER, rbo);
+    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+        fprintf(stderr, "[ERROR]: Framebuffer is not complete.\n");
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+    F32 a = 0.5f;
+    F32 vertices[] = {
+        -a, -a, -a,  0.0f, 0.0f,
+         a, -a, -a,  1.0f, 0.0f,
+         a,  a, -a,  1.0f, 1.0f,
+         a,  a, -a,  1.0f, 1.0f,
+        -a,  a, -a,  0.0f, 1.0f,
+        -a, -a, -a,  0.0f, 0.0f,
+
+        -a, -a,  a,  0.0f, 0.0f,
+         a, -a,  a,  1.0f, 0.0f,
+         a,  a,  a,  1.0f, 1.0f,
+         a,  a,  a,  1.0f, 1.0f,
+        -a,  a,  a,  0.0f, 1.0f,
+        -a, -a,  a,  0.0f, 0.0f,
+ 
+        -a,  a,  a,  1.0f, 0.0f,
+        -a,  a, -a,  1.0f, 1.0f,
+        -a, -a, -a,  0.0f, 1.0f,
+        -a, -a, -a,  0.0f, 1.0f,
+        -a, -a,  a,  0.0f, 0.0f,
+        -a,  a,  a,  1.0f, 0.0f,
+
+         a,  a,  a,  1.0f, 0.0f,
+         a,  a, -a,  1.0f, 1.0f,
+         a, -a, -a,  0.0f, 1.0f,
+         a, -a, -a,  0.0f, 1.0f,
+         a, -a,  a,  0.0f, 0.0f,
+         a,  a,  a,  1.0f, 0.0f,
+
+        -a, -a, -a,  0.0f, 1.0f,
+         a, -a, -a,  1.0f, 1.0f,
+         a, -a,  a,  1.0f, 0.0f,
+         a, -a,  a,  1.0f, 0.0f,
+        -a, -a,  a,  0.0f, 0.0f,
+        -a, -a, -a,  0.0f, 1.0f,
+
+        -a,  a, -a,  0.0f, 1.0f,
+         a,  a, -a,  1.0f, 1.0f,
+         a,  a,  a,  1.0f, 0.0f,
+         a,  a,  a,  1.0f, 0.0f,
+        -a,  a,  a,  0.0f, 0.0f,
+        -a,  a, -a,  0.0f, 1.0f
+    };
+
+    Transform cube_positions[] = {
+        transform_default(),
+        transform_make_translate(v3f(a, 0.0f, -4.0f*a))
+    };
+
+    Transform platform_position =
+        transform_make_scale_translate(v3f(10.0f, 0.2f, 10.0f),
+                                       v3f(0.0f, -(a+(a*0.2f)+0.01f), 0.0f));
+
+    U32 cube_vao, quad_vao, vbo;
+
+    glGenVertexArrays(1, &cube_vao);
+    glBindVertexArray(cube_vao);
+
+    glGenBuffers(1, &vbo);
+    glBindBuffer(GL_ARRAY_BUFFER, vbo);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), 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);
+    
+    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
+    };
+    
+    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);
+
+    Transform window_transforms[] = {
+        transform_make_scale_translate(v3f(0.5f, 0.5f, 0.5f), v3f(0.0f, 0.0f, a+0.1f)),
+        transform_make_scale_translate(v3f(0.5f, 0.5f, 0.5f), v3f(0.0f, 0.0f, 2.0f)),
+        transform_make_scale_translate(v3f(0.5f, 0.5f, 0.5f), v3f(1.0f, 0.0f, -1.0f)),
+        transform_make_scale_translate(v3f(0.5f, 0.5f, 0.5f), v3f(-2.0f, 0.0f, 0.5f)),
+        transform_make_scale_translate(v3f(0.5f, 0.5f, 0.5f), v3f(-3.0f, 0.0f, -3.0f)),
+        transform_make_scale_translate(v3f(0.5f, 0.5f, 0.5f), v3f(3.0f, 0.0f, 0.2)),
+    };
+
+    F32 angle = 0.0f;
+    for (S32 window_index = 0;
+         window_index < (S32)ArrayCount(window_transforms);
+         ++window_index)
+    {
+        Transform *transform = window_transforms+window_index;
+        *transform = transform_rotate(*transform, v3f(0.0f, angle, 0.0f));
+        angle += 30.0f;
+    }
+    
+    F32 target_fps = 60.0f;
+    F32 target_spf = 1.0f/target_fps;
+    camera_pos = v3f(0.0f, 1.0f, 3.0f);
+    
+    F32 last_time = glfwGetTime();
+
+    while (!glfwWindowShouldClose(window))
+    {
+        glfwPollEvents();
+        
+        /* INFO(pryazha): update */
+        V3F left, up, forward;
+        V3F world_up = v3f(0.0f, 1.0f, 0.0f);
+        
+        forward = v3f_norm(v3f_sub(v3f(0.0f, 0.0f, 0.0f), camera_pos));
+        left = v3f_norm(v3f_cross(world_up, forward));
+        up = v3f_cross(forward, left);
+        
+        V3F dp = v3f_zero();
+        F32 speed = 2.0f;
+        if (key_is_pressed(input.move_right))
+            dp = v3f_add(dp, v3f_scalef(left, -speed*dt));
+        if (key_is_pressed(input.move_forward))
+            dp = v3f_add(dp, v3f_scalef(forward, speed*dt));
+        if (key_is_pressed(input.move_left))
+            dp = v3f_add(dp, v3f_scalef(left, speed*dt));
+        if (key_is_pressed(input.move_backward))
+            dp = v3f_add(dp, v3f_scalef(forward, -speed*dt));
+        if (key_is_pressed(input.move_up))
+            dp = v3f_add(dp, v3f_scalef(up, speed*dt));
+        if (key_is_pressed(input.move_down))
+            dp = v3f_add(dp, v3f_scalef(up, -speed*dt));
+
+        input_update_last_state(&input);
+
+        camera_pos = v3f_add(camera_pos, dp);
+
+        Transform sorted_window_transforms[ArrayCount(window_transforms)];
+        MemoryCopyArray(sorted_window_transforms, window_transforms);
+        for (S32 i = 0; i < (S32)ArrayCount(sorted_window_transforms); ++i) {
+            for (S32 pos_index = 1;
+                 pos_index < (S32)ArrayCount(sorted_window_transforms);
+                 ++pos_index)
+            {
+                F32 distance_left = v3f_length(v3f_sub(sorted_window_transforms[pos_index-1].translate, camera_pos));
+                F32 distance_right = v3f_length(v3f_sub(sorted_window_transforms[pos_index].translate, camera_pos));
+                if (distance_left < distance_right) {
+                    Transform temp = sorted_window_transforms[pos_index];
+                    sorted_window_transforms[pos_index] = sorted_window_transforms[pos_index-1];
+                    sorted_window_transforms[pos_index-1] = temp;
+                }
+            }
+        }
+        
+        /* INFO(pryazha): Render */
+        glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+        glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        glEnable(GL_DEPTH_TEST);
+        MAT4 view, projection;
+        view = look_at(camera_pos, v3f(0.0f, 0.0f, 0.0f), v3f(0.0f, 1.0f, 0.0f));
+        projection = perspective(90.0f, (F32)WIDTH/(F32)HEIGHT, 0.1f, 100.0f);
+        glUseProgram(cube_shader);
+        shader_set_mat4fv(cube_shader, "view", view);
+        shader_set_mat4fv(cube_shader, "projection", projection);
+        glBindTexture(GL_TEXTURE_2D, marble_texture);
+        glBindVertexArray(cube_vao);
+        for (S32 transform_index = 0;
+             transform_index < (S32)ArrayCount(cube_positions);
+             ++transform_index)
+        {
+            shader_set_mat4fv(cube_shader, "model", transform_apply(cube_positions[transform_index]));
+            glDrawArrays(GL_TRIANGLES, 0, 36);
+        }
+
+        glBindTexture(GL_TEXTURE_2D, metal_texture);
+        shader_set_mat4fv(cube_shader, "model", transform_apply(platform_position));
+        glDrawArrays(GL_TRIANGLES, 0, 36);
+        glBindVertexArray(0);
+
+        glEnable(GL_BLEND);
+        glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
+        glUseProgram(cube_shader);
+        glBindTexture(GL_TEXTURE_2D, window_texture);
+        shader_set_mat4fv(cube_shader, "view", view);
+        shader_set_mat4fv(cube_shader, "projection", projection);
+        glBindVertexArray(quad_vao);
+        for (S32 window_index = 0;
+             window_index < (S32)ArrayCount(sorted_window_transforms);
+             ++window_index)
+        {
+            shader_set_mat4fv(cube_shader, "model", transform_apply(sorted_window_transforms[window_index]));
+            glDrawArrays(GL_TRIANGLES, 0, 6);
+        }
+        glBindVertexArray(0);
+        glDisable(GL_BLEND);
+
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+        glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT);
+        glUseProgram(screen_shader);
+        glDisable(GL_DEPTH_TEST);
+        glBindTexture(GL_TEXTURE_2D, texture_colorbuffer);
+        glBindVertexArray(quad_vao);
+        shader_set_mat4fv(screen_shader, "model", mat4_identity());
+        glDrawArrays(GL_TRIANGLES, 0, 6);
+        glBindVertexArray(0);
+
+        glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+        glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        glEnable(GL_DEPTH_TEST);
+        V3F target = v3f_add(camera_pos, v3f_negate(forward));
+        view = look_at(camera_pos, target, v3f(0.0f, 1.0f, 0.0f));
+        glUseProgram(cube_shader);
+        shader_set_mat4fv(cube_shader, "view", view);
+        shader_set_mat4fv(cube_shader, "projection", projection);
+        glBindTexture(GL_TEXTURE_2D, marble_texture);
+        glBindVertexArray(cube_vao);
+        for (S32 transform_index = 0;
+             transform_index < (S32)ArrayCount(cube_positions);
+             ++transform_index)
+        {
+            shader_set_mat4fv(cube_shader, "model", transform_apply(cube_positions[transform_index]));
+            glDrawArrays(GL_TRIANGLES, 0, 36);
+        }
+
+        glBindTexture(GL_TEXTURE_2D, metal_texture);
+        shader_set_mat4fv(cube_shader, "model", transform_apply(platform_position));
+        glDrawArrays(GL_TRIANGLES, 0, 36);
+        glBindVertexArray(0);
+
+        glEnable(GL_BLEND);
+        glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
+        glUseProgram(cube_shader);
+        glBindTexture(GL_TEXTURE_2D, window_texture);
+        shader_set_mat4fv(cube_shader, "view", view);
+        shader_set_mat4fv(cube_shader, "projection", projection);
+        glBindVertexArray(quad_vao);
+        for (S32 window_index = 0;
+             window_index < (S32)ArrayCount(sorted_window_transforms);
+             ++window_index)
+        {
+            shader_set_mat4fv(cube_shader, "model", transform_apply(sorted_window_transforms[window_index]));
+            glDrawArrays(GL_TRIANGLES, 0, 6);
+        }
+        glBindVertexArray(0);
+        glDisable(GL_BLEND);
+
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+        glUseProgram(screen_shader);
+        glDisable(GL_DEPTH_TEST);
+        glBindTexture(GL_TEXTURE_2D, texture_colorbuffer);
+        glBindVertexArray(quad_vao);
+        MAT4 model = transform_apply(transform_make_scale_translate(v3f(0.3f, 0.3f, 0.3f), v3f(-0.7f, 0.7f, 0.0f)));
+        shader_set_mat4fv(screen_shader, "model", model);
+        glDrawArrays(GL_TRIANGLES, 0, 6);
+        glBindVertexArray(0);
+
+        glfwSwapBuffers(window);
+
+        F32 elapsed = glfwGetTime()-last_time;
+        if (elapsed < target_spf)
+        {
+            U32 sleep_time = (U32)(target_spf-elapsed);
+            if (sleep_time > 0)
+                sleep(sleep_time);
+        }
+        F32 current_time = glfwGetTime();
+        dt = current_time-last_time;
+        last_time = current_time;
+    }
+
+    glfwTerminate();
+    return(0);
+}