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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;
State state;
S32 width, height;
Input input;
if (glfwInit() == GLFW_FALSE) {
fprintf(stderr, "[ERROR] Failed to initialize glfw.\n");
return(1);
}
width = 1024;
height = 768;
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
window = glfwCreateWindow(width, height, "Face culling", 0, 0);
if (!window) {
fprintf(stderr, "[ERROR] Failed to create window.\n");
glfwTerminate();
return(1);
}
glfwMakeContextCurrent(window);
if (glewInit() != GLEW_OK) {
fprintf(stderr, "[ERROR] Failed to initialize glew.\n");
glfwTerminate();
return(1);
}
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glFrontFace(GL_CW);
glCullFace(GL_BACK);
U32 shader = create_shader_program("shaders/face_culling.vert",
"shaders/face_culling.frag");
U32 grid_texture = load_texture("../../data/textures/grid.png");
F32 a = 0.5f;
/* NOTE(pryazha): Counter-clockwise order */
F32 cube_vertices_ccw[] = {
/* NOTE(pryazha): Back face */
a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, a, -a, 1.0f, 1.0f, /* top-right */
a, a, -a, 0.0f, 1.0f, /* top-left */
a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, -a, -a, 1.0f, 0.0f, /* bottom-right */
-a, a, -a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Front face */
-a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, a, a, 1.0f, 1.0f, /* top-right */
-a, a, a, 0.0f, 1.0f, /* top-left */
-a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, -a, a, 1.0f, 0.0f, /* bottom-right */
a, a, a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Left face */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, a, a, 1.0f, 1.0f, /* top-right */
-a, a, -a, 0.0f, 1.0f, /* top-left */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, -a, a, 1.0f, 0.0f, /* bottom-right */
-a, a, a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Right face */
a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, a, -a, 1.0f, 1.0f, /* top-right */
a, a, a, 0.0f, 1.0f, /* top-left */
a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, -a, -a, 1.0f, 0.0f, /* bottom-right */
a, a, -a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Top face */
-a, a, a, 0.0f, 0.0f, /* bottom-left */
a, a, -a, 1.0f, 1.0f, /* top-right */
-a, a, -a, 0.0f, 1.0f, /* top-left */
-a, a, a, 0.0f, 0.0f, /* bottom-left */
a, a, a, 1.0f, 0.0f, /* bottom-right */
a, a, -a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Bottom face */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
a, -a, a, 1.0f, 1.0f, /* top-right */
-a, -a, a, 0.0f, 1.0f, /* top-left */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
a, -a, -a, 1.0f, 0.0f, /* bottom-right */
a, -a, a, 1.0f, 1.0f, /* top-right */
};
F32 cube_vertices_cw[] = {
/* NOTE(pryazha): Back face */
a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, a, -a, 1.0f, 1.0f, /* top-right */
-a, -a, -a, 1.0f, 0.0f, /* bottom-right */
a, -a, -a, 0.0f, 0.0f, /* bottom-left */
a, a, -a, 0.0f, 1.0f, /* top-left */
-a, a, -a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Front face */
-a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, a, a, 1.0f, 1.0f, /* top-right */
a, -a, a, 1.0f, 0.0f, /* bottom-right */
-a, -a, a, 0.0f, 0.0f, /* bottom-left */
-a, a, a, 0.0f, 1.0f, /* top-left */
a, a, a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Left face */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, a, a, 1.0f, 1.0f, /* top-right */
-a, -a, a, 1.0f, 0.0f, /* bottom-right */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, a, -a, 0.0f, 1.0f, /* top-left */
-a, a, a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Right face */
a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, a, -a, 1.0f, 1.0f, /* top-right */
a, -a, -a, 1.0f, 0.0f, /* bottom-right */
a, -a, a, 0.0f, 0.0f, /* bottom-left */
a, a, a, 0.0f, 1.0f, /* top-left */
a, a, -a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Top face */
-a, a, a, 0.0f, 0.0f, /* bottom-left */
a, a, -a, 1.0f, 1.0f, /* top-right */
a, a, a, 1.0f, 0.0f, /* bottom-right */
-a, a, a, 0.0f, 0.0f, /* bottom-left */
-a, a, -a, 0.0f, 1.0f, /* top-left */
a, a, -a, 1.0f, 1.0f, /* top-right */
/* NOTE(pryazha): Bottom face */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
a, -a, a, 1.0f, 1.0f, /* top-right */
a, -a, -a, 1.0f, 0.0f, /* bottom-right */
-a, -a, -a, 0.0f, 0.0f, /* bottom-left */
-a, -a, a, 0.0f, 1.0f, /* top-left */
a, -a, a, 1.0f, 1.0f, /* top-right */
};
U32 cube_vao, vbo;
glGenVertexArrays(1, &cube_vao);
glBindVertexArray(cube_vao);
glGenBuffers(1, &vbo);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
glBufferData(GL_ARRAY_BUFFER, sizeof(cube_vertices_cw), cube_vertices_cw, 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 cube_transform = transform_default();
state.camera = (Camera) {
v3f(0.0f, 0.0f, 3.0f),
90.0f, 0.1f, 100.0f,
0.0f, 0.0f
};
F32 target_fps = 60.0f;
F32 target_spf = 1.0f/target_fps;
F32 last_time = glfwGetTime();
F32 d_angle = 45.0f;
while (!glfwWindowShouldClose(window)) {
glfwPollEvents();
process_glfw_keyboard(window, &input);
glfwGetFramebufferSize(window, &width, &height);
/* INFO(pryazha): update */
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);
input_update_last_state(&input);
/* INFO(pryazha): Render */
MAT4 model, view, proj;
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);
cube_transform = transform_rotate(cube_transform,
v3f(0.0f, d_angle*state.dt, 0.0f));
model = transform_apply(cube_transform);
glViewport(0, 0, width, height);
glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(shader);
glBindTexture(GL_TEXTURE_2D, grid_texture);
shader_set_mat4fv(shader, "model", model);
shader_set_mat4fv(shader, "view", view);
shader_set_mat4fv(shader, "proj", proj);
glBindVertexArray(cube_vao);
glDrawArrays(GL_TRIANGLES, 0, 36);
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();
state.dt = current_time-last_time;
last_time = current_time;
}
glfwTerminate();
return(0);
}
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