path: root/advanced_opengl/7.uniform_buffer/uniform_buffer.c

#include "GL/glew.h"
#include "GLFW/glfw3.h"

#include "pwyazh.h"

#include "pwyazh_GL.h"

#include "common.h"

#include <unistd.h>

#define WIDTH 1024
#define HEIGHT 768

static V3F camera_pos;
static F32 dt;
static Input input;
static B32 first_mouse = 1;

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;
    }
}

void
cursor_pos_callback(GLFWwindow* window, double xpos, double ypos)
{
    if (first_mouse)
    {
        input.last_mouse_pos = v2f(xpos, ypos);
        first_mouse = 0;
    }
    input.mouse_offset = v2f(input.mouse_offset.x+((F32)xpos-input.last_mouse_pos.x),
                             input.mouse_offset.y+((F32)ypos-input.last_mouse_pos.y));
    input.last_mouse_pos = v2f((F32)xpos, (F32)ypos);
}

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, "Advanced data (uniform buffer)", 0, 0);
    if (!window)
    {
        fprintf(stderr, "[ERROR] Failed to create window.\n");
        glfwTerminate();
        return(1);
    }
    
    glfwMakeContextCurrent(window);
    
    glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
    
    glfwSetKeyCallback(window, key_callback);
    glfwSetCursorPosCallback(window, cursor_pos_callback);
    
    if (glewInit() != GLEW_OK)
    {
        fprintf(stderr, "[ERROR] Failed to initialize glew.\n");
        glfwTerminate();
        return(1);
    }
    
    U32 skybox_shader = create_shader_program("shaders/skybox.vs", "shaders/skybox.fs");
    U32 cube_shader = create_shader_program("shaders/cube.vs", "shaders/cube.fs");
    U32 color_cube_shader = create_shader_program("shaders/color_cube.vs",
                                                  "shaders/color_cube.fs");
    
    U32 skybox_matrices = glGetUniformBlockIndex(skybox_shader, "Matrices");
    U32 cube_matrices = glGetUniformBlockIndex(cube_shader, "Matrices");
    U32 color_cube_matrices = glGetUniformBlockIndex(color_cube_shader, "Matrices");
    
    glUniformBlockBinding(skybox_shader, skybox_matrices, 0);
    glUniformBlockBinding(cube_shader, cube_matrices, 0);
    glUniformBlockBinding(color_cube_shader, color_cube_matrices, 0);
    
    U32 matrices_ubo;
    glGenBuffers(1, &matrices_ubo);
    glBindBuffer(GL_UNIFORM_BUFFER, matrices_ubo);
    glBufferData(GL_UNIFORM_BUFFER, 2*sizeof(MAT4), 0, GL_STATIC_DRAW);
    glBindBuffer(GL_UNIFORM_BUFFER, 0);
    glBindBufferRange(GL_UNIFORM_BUFFER, 0, matrices_ubo, 0, 2*sizeof(MAT4));
    
    U32 grid_texture = load_texture("../../data/textures/grid.png");
    
    const char *cube_texture_filenames[6] = {
        "../../data/textures/skybox/right.jpg",
        "../../data/textures/skybox/left.jpg",
        "../../data/textures/skybox/top.jpg",
        "../../data/textures/skybox/bottom.jpg",
        "../../data/textures/skybox/front.jpg",
        "../../data/textures/skybox/back.jpg"
    };
    U32 skybox_texture = load_cubemap(cube_texture_filenames);
    
    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 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, 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);
    
    a = 1.0f;
    F32 skybox_cube_vertices[] = {
        -a, -a, -a,
        a, -a, -a,
        a,  a, -a,
        a,  a, -a,
        -a,  a, -a,
        -a, -a, -a,
        
        -a, -a,  a,
        a, -a,  a,
        a,  a,  a,
        a,  a,  a,
        -a,  a,  a,
        -a, -a,  a,
        
        -a,  a,  a,
        -a,  a, -a,
        -a, -a, -a,
        -a, -a, -a,
        -a, -a,  a,
        -a,  a,  a,
        
        a,  a,  a,
        a,  a, -a,
        a, -a, -a,
        a, -a, -a,
        a, -a,  a,
        a,  a,  a,
        
        -a, -a, -a,
        a, -a, -a,
        a, -a,  a,
        a, -a,  a,
        -a, -a,  a,
        -a, -a, -a,
        
        -a,  a, -a,
        a,  a, -a,
        a,  a,  a,
        a,  a,  a,
        -a,  a,  a,
        -a,  a, -a,
    };
    
    U32 skybox_cube_vao;
    glGenVertexArrays(1, &skybox_cube_vao);
    glBindVertexArray(skybox_cube_vao);
    glGenBuffers(1, &vbo);
    glBindBuffer(GL_ARRAY_BUFFER, vbo);
    glBufferData(GL_ARRAY_BUFFER, sizeof(skybox_cube_vertices), skybox_cube_vertices, GL_STATIC_DRAW);
    glEnableVertexAttribArray(0);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(F32), (void *)0);
    glBindVertexArray(0);
    
    F32 target_fps = 60.0f;
    F32 target_spf = 1.0f/target_fps;
    camera_pos = v3f(0.0f, 1.0f, 3.0f);
    F32 yaw = 0.0f, pitch = 0.0f;
    
    F32 last_time = glfwGetTime();
    
    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LEQUAL);
    
    MAT4 view, projection;
    projection = perspective(90.0f, (F32)WIDTH/(F32)HEIGHT, 0.1f, 100.0f);
    glBindBuffer(GL_UNIFORM_BUFFER, matrices_ubo);
    glBufferSubData(GL_UNIFORM_BUFFER, 0, sizeof(MAT4), (const void *)&projection);
    glBindBuffer(GL_UNIFORM_BUFFER, 0);
    view = mat4_make_translate(v3f_negate(camera_pos));
    view = mat4_rotate_angles(view, v3f(pitch, yaw, 0.0f));
    
    while (!glfwWindowShouldClose(window))
    {
        glfwPollEvents();
        
        /* INFO(pryazha): update */
        
        V3F left, up, forward;
        
        left = v3f(-view.m0.x, -view.m1.x, -view.m2.x);
        up = v3f(view.m0.y, view.m1.y, view.m2.y);
        forward = v3f(-view.m0.z, -view.m1.z, -view.m2.z);
        
        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);
        
        /* NOTE(pryazha): Mouse handling */
        F32 sensitivity = 0.1f;
        input.mouse_offset = v2f_scalef(input.mouse_offset, sensitivity);
        yaw += input.mouse_offset.x;
        pitch += input.mouse_offset.y;
        if (pitch > 89.0f)
            pitch = 89.0f;
        if (pitch < -89.0f)
            pitch = -89.0f;
        input.mouse_offset = v2f_zero();
        
        view = mat4_make_translate(v3f_negate(camera_pos));
        view = mat4_rotate_angles(view, v3f(pitch, yaw, 0.0f));
        glBindBuffer(GL_UNIFORM_BUFFER, matrices_ubo);
        glBufferSubData(GL_UNIFORM_BUFFER, sizeof(MAT4), sizeof(MAT4), (const void *)&view);
        glBindBuffer(GL_UNIFORM_BUFFER, 0);
        
        /* NOTE(pryazha): Render */
        glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        
        glUseProgram(cube_shader);
        shader_set_mat4fv(cube_shader, "model", mat4_make_translate(v3f(-2.0f, 0.0f, 0.0f)));
        glBindTexture(GL_TEXTURE_2D, grid_texture);
        glBindVertexArray(cube_vao);
        glDrawArrays(GL_TRIANGLES, 0, 36);
        glBindTexture(GL_TEXTURE_2D, 0);
        glBindVertexArray(0);
        
        glUseProgram(cube_shader);
        shader_set_mat4fv(cube_shader, "model", transform_apply(platform_position));
        glBindTexture(GL_TEXTURE_2D, grid_texture);
        glBindVertexArray(cube_vao);
        glDrawArrays(GL_TRIANGLES, 0, 36);
        glBindTexture(GL_TEXTURE_2D, 0);
        glBindVertexArray(0);
        
        glUseProgram(color_cube_shader);
        shader_set_mat4fv(cube_shader, "model", mat4_make_translate(v3f(2.0f, 0.0f, 0.0f)));
        glBindVertexArray(cube_vao);
        glDrawArrays(GL_TRIANGLES, 0, 36);
        glBindVertexArray(0);
        
        glUseProgram(skybox_shader);
        MAT4 rotate_view = mat4_identity();
        rotate_view.m0 = v4f(view.m0.x, view.m0.y, view.m0.z, 0.0f);
        rotate_view.m1 = v4f(view.m1.x, view.m1.y, view.m1.z, 0.0f);
        rotate_view.m2 = v4f(view.m2.x, view.m2.y, view.m2.z, 0.0f);
        glBindBuffer(GL_UNIFORM_BUFFER, matrices_ubo);
        glBufferSubData(GL_UNIFORM_BUFFER, sizeof(MAT4), sizeof(MAT4), (const void *)&rotate_view);
        glBindBuffer(GL_UNIFORM_BUFFER, 0);
        glBindVertexArray(skybox_cube_vao);
        glBindTexture(GL_TEXTURE_CUBE_MAP, skybox_texture);
        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();
        dt = current_time-last_time;
        last_time = current_time;
    }
    
    glfwTerminate();
    return(0);
}