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Diffstat (limited to 'advanced_opengl/8.geometry_shader/geometry_shader.c')
-rw-r--r--advanced_opengl/8.geometry_shader/geometry_shader.c339
1 files changed, 339 insertions, 0 deletions
diff --git a/advanced_opengl/8.geometry_shader/geometry_shader.c b/advanced_opengl/8.geometry_shader/geometry_shader.c
new file mode 100644
index 0000000..678708c
--- /dev/null
+++ b/advanced_opengl/8.geometry_shader/geometry_shader.c
@@ -0,0 +1,339 @@
+#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 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_SPACE: {
+ input.jump.state = KeyState_PRESS;
+ } break;
+ }
+ } break;
+
+ case GLFW_RELEASE: {
+ switch (key)
+ {
+ case GLFW_KEY_SPACE: {
+ input.jump.state = KeyState_RELEASE;
+ } break;
+ }
+ } break;
+ }
+}
+
+void
+draw_cube(U32 cube_vao, U32 texture)
+{
+ glBindVertexArray(cube_vao);
+ glBindTexture(GL_TEXTURE_2D, texture);
+ glDrawArrays(GL_TRIANGLES, 0, 36);
+ glBindTexture(GL_TEXTURE_2D, 0);
+ glBindVertexArray(0);
+}
+
+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);
+ }
+
+ glEnable(GL_DEPTH_TEST);
+
+ U32 shader = create_shader_program_geom("shaders/base.vs",
+ "shaders/base.fs",
+ "shaders/base.gs");
+ U32 explosion_shader = create_shader_program_geom("shaders/explosion.vs",
+ "shaders/explosion.fs",
+ "shaders/explosion.gs");
+ U32 normals_shader = create_shader_program_geom("shaders/normals.vs",
+ "shaders/normals.fs",
+ "shaders/normals.gs");
+ U32 basic_shader = create_shader_program("shaders/basic.vs", "shaders/basic.fs");
+
+ U32 grid_texture = load_texture("../../data/textures/grid.png");
+
+ F32 points[] = {
+ -0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
+ 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
+ 0.5f, -0.5f, 0.0f, 0.0f, 1.0f,
+ -0.5f, -0.5f, 1.0f, 1.0f, 0.0f
+ };
+
+ GLuint points_vao, vbo;
+ glGenVertexArrays(1, &points_vao);
+ glBindVertexArray(points_vao);
+ glGenBuffers(1, &vbo);
+ glBindBuffer(GL_ARRAY_BUFFER, vbo);
+ glBufferData(GL_ARRAY_BUFFER, sizeof(points), points, GL_STATIC_DRAW);
+ glEnableVertexAttribArray(0);
+ glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)0);
+ glEnableVertexAttribArray(1);
+ glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 5*sizeof(F32), (void *)(2*sizeof(F32)));
+ glBindVertexArray(0);
+
+ F32 a = 0.5f;
+ /* NOTE(pryazha): Counter-clockwise order */
+ F32 cube_vertices[] = {
+ /* 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 */
+ };
+
+ U32 cube_vao;
+ glGenVertexArrays(1, &cube_vao);
+ glBindVertexArray(cube_vao);
+ glGenBuffers(1, &vbo);
+ glBindBuffer(GL_ARRAY_BUFFER, vbo);
+ glBufferData(GL_ARRAY_BUFFER, sizeof(cube_vertices), cube_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 vertices[] = {
+ -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,
+ 0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f,
+ 0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,
+ 0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,
+ -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f,
+ -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,
+
+ -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,
+ 0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f,
+ 0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,
+ 0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,
+ -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f,
+ -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,
+
+ -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
+ -0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
+ -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
+ -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
+ -0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
+ -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
+
+ 0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
+ 0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
+ 0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
+ 0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,
+ 0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
+ 0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
+
+ -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f,
+ 0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f,
+ 0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,
+ 0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,
+ -0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f,
+ -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f,
+
+ -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,
+ 0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f,
+ 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
+ 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f,
+ -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f,
+ -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f
+ };
+
+ U32 normals_cube_vao;
+ glGenVertexArrays(1, &normals_cube_vao);
+ glBindVertexArray(normals_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, 8*sizeof(F32), (void *)0);
+ glEnableVertexAttribArray(1);
+ glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8*sizeof(F32), (void *)(3*sizeof(F32)));
+ glEnableVertexAttribArray(2);
+ glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8*sizeof(F32), (void *)(6*sizeof(F32)));
+ glBindVertexArray(0);
+
+ F32 target_fps = 60.0f;
+ F32 target_spf = 1.0f/target_fps;
+
+ F32 last_time = glfwGetTime();
+ F32 time = last_time;
+
+ S32 scene = 0;
+
+ while (!glfwWindowShouldClose(window))
+ {
+ glfwPollEvents();
+
+ /* NOTE(pryazha): Update */
+ if (key_first_press(input.jump))
+ {
+ scene++;
+ scene %= 3;
+ }
+
+ input_update_last_state(&input);
+
+ /* NOTE(pryazha): Render */
+ glClearColor(0.15f, 0.15f, 0.15f, 1.0f);
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ if (scene == 0)
+ {
+ glUseProgram(shader);
+ glBindVertexArray(points_vao);
+ glDrawArrays(GL_POINTS, 0, 4);
+ glBindVertexArray(0);
+ }
+ else if (scene == 1)
+ {
+ F32 radius = 2.0f;
+ F32 x = f32_sin(0.5*time)*radius;
+ F32 z = f32_cos(0.5*time)*radius;
+ MAT4 projection = perspective(90.0f, (F32)WIDTH/(F32)HEIGHT, 0.1f, 100.0f);
+ MAT4 view = look_at(v3f(x, 1.0f, z), v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
+ MAT4 model = mat4_identity();
+ glUseProgram(explosion_shader);
+ shader_set_mat4fv(explosion_shader, "projection", projection);
+ shader_set_mat4fv(explosion_shader, "view", view);
+ shader_set_mat4fv(explosion_shader, "model", model);
+ shader_set_1f(explosion_shader, "time", time);
+ glBindVertexArray(cube_vao);
+ glBindTexture(GL_TEXTURE_2D, grid_texture);
+ glDrawArrays(GL_TRIANGLES, 0, 36);
+ glBindVertexArray(0);
+ }
+ else
+ {
+ MAT4 projection, view, model;
+ F32 radius, x, z;
+
+ radius = 2.0f;
+ x = f32_sin(0.5*time)*radius;
+ z = f32_cos(0.5*time)*radius;
+
+ projection = perspective(90.0f, (F32)WIDTH/(F32)HEIGHT, 0.1f, 100.0f);
+ view = look_at(v3f(x, 1.0f, z), v3f_zero(), v3f(0.0f, 1.0f, 0.0f));
+ model = mat4_identity();
+
+ glUseProgram(basic_shader);
+ shader_set_mat4fv(basic_shader, "projection", projection);
+ shader_set_mat4fv(basic_shader, "view", view);
+ shader_set_mat4fv(basic_shader, "model", model);
+ draw_cube(normals_cube_vao, grid_texture);
+
+ glUseProgram(normals_shader);
+ shader_set_mat4fv(normals_shader, "projection", projection);
+ shader_set_mat4fv(normals_shader, "view", view);
+ shader_set_mat4fv(normals_shader, "model", model);
+ draw_cube(normals_cube_vao, grid_texture);
+ }
+
+ 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;
+ time += dt;
+ last_time = current_time;
+ }
+
+ glDeleteBuffers(1, &vbo);
+ glDeleteVertexArrays(1, &points_vao);
+
+ glfwTerminate();
+ return(0);
+}