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-rwxr-xr-xadvanced_opengl/5.framebuffers/build.sh5
-rwxr-xr-xadvanced_opengl/5.framebuffers/framebuffersbin0 -> 1288800 bytes
-rw-r--r--advanced_opengl/5.framebuffers/framebuffers.c424
-rw-r--r--advanced_opengl/5.framebuffers/shaders/cube.fs13
-rw-r--r--advanced_opengl/5.framebuffers/shaders/cube.vs17
-rw-r--r--advanced_opengl/5.framebuffers/shaders/screen.fs119
-rw-r--r--advanced_opengl/5.framebuffers/shaders/screen.vs14
7 files changed, 592 insertions, 0 deletions
diff --git a/advanced_opengl/5.framebuffers/build.sh b/advanced_opengl/5.framebuffers/build.sh
new file mode 100755
index 0000000..58a1162
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/build.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+. ../../config
+TARGET='framebuffers'
+set -x
+gcc -o $TARGET $CFLAGS $INCLUDE $LFLAGS $TARGET.c $LIBS && ./$TARGET
diff --git a/advanced_opengl/5.framebuffers/framebuffers b/advanced_opengl/5.framebuffers/framebuffers
new file mode 100755
index 0000000..4b2c4c5
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/framebuffers
Binary files differ
diff --git a/advanced_opengl/5.framebuffers/framebuffers.c b/advanced_opengl/5.framebuffers/framebuffers.c
new file mode 100644
index 0000000..a0523cc
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/framebuffers.c
@@ -0,0 +1,424 @@
+#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;
+
+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, "Framebuffers", 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);
+}
diff --git a/advanced_opengl/5.framebuffers/shaders/cube.fs b/advanced_opengl/5.framebuffers/shaders/cube.fs
new file mode 100644
index 0000000..f58c5d3
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/shaders/cube.fs
@@ -0,0 +1,13 @@
+#version 330 core
+
+out vec4 frag_color;
+
+in vec2 tex_coords;
+
+uniform sampler2D texture1;
+
+void
+main(void)
+{
+ frag_color = texture(texture1, tex_coords);
+}
diff --git a/advanced_opengl/5.framebuffers/shaders/cube.vs b/advanced_opengl/5.framebuffers/shaders/cube.vs
new file mode 100644
index 0000000..3c11932
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/shaders/cube.vs
@@ -0,0 +1,17 @@
+#version 330 core
+
+layout(location = 0) in vec3 apos;
+layout(location = 1) in vec2 atex_coords;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+out vec2 tex_coords;
+
+void
+main(void)
+{
+ gl_Position = projection*view*model*vec4(apos, 1.0f);
+ tex_coords = atex_coords;
+}
diff --git a/advanced_opengl/5.framebuffers/shaders/screen.fs b/advanced_opengl/5.framebuffers/shaders/screen.fs
new file mode 100644
index 0000000..8f0b2da
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/shaders/screen.fs
@@ -0,0 +1,119 @@
+#version 330 core
+
+out vec4 frag_color;
+
+in vec2 tex_coords;
+
+uniform sampler2D texture1;
+
+vec4
+inversion()
+{
+ vec4 result = vec4(1.0f-vec3(texture(texture1, tex_coords)), 1.0f);
+ return(result);
+}
+
+vec4
+grayscale_average()
+{
+ vec4 tex_color = texture(texture1, tex_coords);
+ float average = (tex_color.r+tex_color.g+tex_color.b)/3.0f;
+ vec4 result = vec4(average, average, average, 1.0f);
+ return(result);
+}
+
+vec4
+grayscale_weights()
+{
+ vec4 tex_color = texture(texture1, tex_coords);
+ float average = 0.2126*tex_color.r+0.7152*tex_color.g+0.0722f*tex_color.b;
+ vec4 result = vec4(average, average, average, 1.0f);
+ return(result);
+}
+
+const float offset = 1.0f/300.0f;
+
+vec4
+kernel_effect(float[9] kernel)
+{
+ vec2 offsets[9] = vec2[](
+ vec2(-offset, offset), /* top-left */
+ vec2(0.0f, offset), /* top-center */
+ vec2(offset, offset), /* top-right */
+ vec2(-offset, 0.0f), /* center-left */
+ vec2(0.0f, 0.0f), /* center-center */
+ vec2(offset, 0.0f), /* center-right */
+ vec2(-offset, -offset), /* bottom-left */
+ vec2(0.0f, -offset), /* bottom-center */
+ vec2(offset, -offset) /* bottom-right */
+ );
+
+ vec3 sample_texture[9];
+ for (int offset_index = 0;
+ offset_index < 9;
+ ++offset_index)
+ {
+ sample_texture[offset_index] =
+ vec3(texture(texture1, tex_coords+offsets[offset_index]));
+ }
+
+ vec3 color = vec3(0.0f);
+ for (int i = 0; i < 9; ++i)
+ color += sample_texture[i]*kernel[i];
+
+ return(vec4(color, 1.0f));
+}
+
+void
+main(void)
+{
+ float strange_kernel[9] = float[](
+ -1, -1, -1,
+ -1, 9, -1,
+ -1, -1, -1
+ );
+
+ float gaussian_blur_kernel[9] = float[](
+ 1.0f/16.0f, 2.0f/16.0f, 1.0f/16.0f,
+ 2.0f/16.0f, 4.0f/16.0f, 2.0f/16.0f,
+ 1.0f/16.0f, 2.0f/16.0f, 1.0f/16.0f
+ );
+
+ float box_blur_kernel[9] = float[](
+ 1.0f/9.0f, 1.0f/9.0f, 1.0f/9.0f,
+ 1.0f/9.0f, 1.0f/9.0f, 1.0f/9.0f,
+ 1.0f/9.0f, 1.0f/9.0f, 1.0f/9.0f
+ );
+
+ float edge_detection_kernel[9] = float[](
+ 1.0f, 1.0f, 1.0f,
+ 1.0f, -8.0f, 1.0f,
+ 1.0f, 1.0f, 1.0f
+ );
+
+ float sharpening_kernel[9] = float[](
+ 0.0f, -1.0f, 0.0f,
+ -1.0f, 5.0f, -1.0f,
+ 0.0f, -1.0f, 0.0f
+ );
+
+ float sobel_kernel_vertical[9] = float[](
+ -1.0f, 0.0f, 1.0f,
+ -2.0f, 0.0f, 2.0f,
+ -1.0f, 0.0f, 0.0f
+ );
+ float sobel_kernel_horizontal[9] = float[](
+ -1.0f, -2.0f, -1.0f,
+ 0.0f, 0.0f, 0.0f,
+ 1.0f, 2.0f, 1.0f
+ );
+
+ float funny_kernel[9] = float[](
+ 1.0f, 1.0f, 1.0f,
+ 1.0f, -4.0f, 1.0f,
+ 1.0f, 1.0f, 1.0f
+ );
+
+ frag_color = kernel_effect(funny_kernel);
+ frag_color *= vec4(0.76f, 0.47f, 0.84f, 1.0f);
+}
diff --git a/advanced_opengl/5.framebuffers/shaders/screen.vs b/advanced_opengl/5.framebuffers/shaders/screen.vs
new file mode 100644
index 0000000..157dde2
--- /dev/null
+++ b/advanced_opengl/5.framebuffers/shaders/screen.vs
@@ -0,0 +1,14 @@
+#version 330 core
+layout(location = 0) in vec3 apos;
+layout(location = 1) in vec2 atex_coords;
+
+out vec2 tex_coords;
+
+uniform mat4 model;
+
+void
+main(void)
+{
+ gl_Position = model*vec4(apos, 1.0f);
+ tex_coords = atex_coords;
+}