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#include "GL/glew.h"
#include "GLFW/glfw3.h"
#include "pwyazh.h"
#include "pwyazh_GL.h"
#include "common.h"
int main(void)
{
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);
}
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