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-rw-r--r--src/gl.c325
1 files changed, 0 insertions, 325 deletions
diff --git a/src/gl.c b/src/gl.c
deleted file mode 100644
index 09c7e1d..0000000
--- a/src/gl.c
+++ /dev/null
@@ -1,325 +0,0 @@
-#include <epoxy/gl.h>
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include "gl.h"
-#include "log.h"
-#include "xmalloc.h"
-
-#define max(a, b) ((a) > (b) ? (a) : (b))
-
-static void load_shader(GLuint shader, const char *filename);
-static GLuint create_shader_program(const char *vert, const char *frag);
-static void GLAPIENTRY MessageCallback(
- GLenum source,
- GLenum type,
- GLuint id,
- GLenum severity,
- GLsizei length,
- const GLchar* message,
- const void* userParam);
-static const char *gl_debug_source_string(GLenum type);
-static const char *gl_debug_type_string(GLenum type);
-static const char *gl_debug_severity_string(GLenum type);
-
-
-void gl_initialise(struct gl *gl, struct image *texture)
-{
-#ifdef DEBUG
- //glEnable(GL_DEBUG_OUTPUT);
- //glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
- //glDebugMessageCallback(MessageCallback, 0);
-#endif
- if (texture == NULL || texture->buffer == NULL) {
- return;
- }
-
- /* Compile and link the shader programs */
- gl->shader = create_shader_program(
- SHADER_PATH "vert.vert",
- SHADER_PATH "frag.frag"
- );
- glUseProgram(gl->shader);
- glUniform1i(glGetUniformLocation(gl->shader, "tex"), 0);
-
- /* Create a vertex buffer for a quad filling the screen */
- float vertices[] = {
- // Position Texcoords
- -1.0f, 1.0f, 0.0f, 0.0f, // Top-left
- 1.0f, 1.0f, 1.0f, 0.0f, // Top-right
- 1.0f, -1.0f, 1.0f, 1.0f, // Bottom-right
- -1.0f, -1.0f, 0.0f, 1.0f // Bottom-left
- };
-
- glGenBuffers(1, &gl->vbo);
- glBindBuffer(GL_ARRAY_BUFFER, gl->vbo);
- glBufferData(
- GL_ARRAY_BUFFER,
- sizeof(vertices),
- vertices,
- GL_STATIC_DRAW);
-
- /*
- * Create a vertex array and enable vertex attributes for the shaders.
- */
- glGenVertexArrays(1, &gl->vao);
- glBindVertexArray(gl->vao);
-
- GLint posAttrib = glGetAttribLocation(gl->shader, "position");
- glVertexAttribPointer(
- posAttrib,
- 2,
- GL_FLOAT,
- GL_FALSE,
- 4*sizeof(float),
- 0);
- glEnableVertexAttribArray(posAttrib);
-
- GLint texAttrib = glGetAttribLocation(gl->shader, "texcoord");
- glVertexAttribPointer(
- texAttrib,
- 2,
- GL_FLOAT,
- GL_FALSE,
- 4*sizeof(float),
- (void *)(2*sizeof(float)));
- glEnableVertexAttribArray(texAttrib);
-
- glBindVertexArray(0);
-
- /*
- * Create the element buffer object that will actually be drawn via
- * glDrawElements().
- */
- GLubyte elements[] = {
- 0, 1, 2,
- 2, 3, 0
- };
-
- glGenBuffers(1, &gl->ebo);
- glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, gl->ebo);
- glBufferData(
- GL_ELEMENT_ARRAY_BUFFER,
- sizeof(elements),
- elements,
- GL_STATIC_DRAW);
- glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
- glBindBuffer(GL_ARRAY_BUFFER, 0);
-
- /* Create the texture we'll draw to */
- glGenTextures(1, &gl->texture);
- glBindTexture(GL_TEXTURE_2D, gl->texture);
- glTexImage2D(
- GL_TEXTURE_2D,
- 0,
- GL_RGBA,
- texture->width,
- texture->height,
- 0,
- /*
- * On little-endian processors, textures from Cairo
- * have to have their red and blue channels swapped.
- */
- texture->swizzle ? GL_BGRA : GL_RGBA,
- GL_UNSIGNED_BYTE,
- (GLvoid *)texture->buffer);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-
- /* Bind the actual bits we'll be using to render */
- glBindVertexArray(gl->vao);
- glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, gl->ebo);
-}
-
-void gl_destroy(struct gl *gl)
-{
- glDeleteProgram(gl->shader);
- glDeleteTextures(1, &gl->texture);
- glDeleteBuffers(1, &gl->ebo);
- glDeleteVertexArrays(1, &gl->vao);
- glDeleteBuffers(1, &gl->vbo);
-}
-
-void gl_clear(struct gl *gl, struct color *color)
-{
- glClearColor(color->r, color->g, color->b, color->a);
- glClear(GL_COLOR_BUFFER_BIT);
-}
-
-void gl_draw_texture(
- struct gl *gl,
- struct image *texture,
- int32_t x,
- int32_t y,
- int32_t width,
- int32_t height)
-{
- if (texture->redraw) {
- glTexSubImage2D(
- GL_TEXTURE_2D,
- 0,
- 0,
- 0,
- texture->width,
- texture->height,
- texture->swizzle ? GL_BGRA : GL_RGBA,
- GL_UNSIGNED_BYTE,
- (GLvoid *)texture->buffer);
- texture->redraw = false;
- }
-
- glViewport(x, y, width, height);
- glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_BYTE, NULL);
-}
-
-void load_shader(GLuint shader, const char *filename)
-{
- errno = 0;
- FILE *fp = fopen(filename, "rb");
- if (!fp) {
- log_error("Failed to load shader %s: %s.\n",
- filename, strerror(errno));
- exit(EXIT_FAILURE);
- }
- if (fseek(fp, 0, SEEK_END) != 0) {
- log_error("Failed to load shader %s: %s.\n",
- filename, strerror(errno));
- fclose(fp);
- exit(EXIT_FAILURE);
- }
- long size = ftell(fp);
- if (size <= 0) {
- log_error("Failed to load shader %s: %s.\n",
- filename, strerror(errno));
- fclose(fp);
- exit(EXIT_FAILURE);
- }
- unsigned long usize = (unsigned long) size;
- GLchar *source = xmalloc(usize + 1);
- rewind(fp);
- if (fread(source, 1, usize, fp) != usize) {
- log_error("Failed to load shader %s: %s.\n",
- filename, strerror(errno));
- fclose(fp);
- exit(EXIT_FAILURE);
- }
- fclose(fp);
- source[usize] = '\0';
- glShaderSource(shader, 1, (const GLchar *const *)&source, NULL);
- free(source);
-
- glCompileShader(shader);
-
- GLint status;
- glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
- if (status != GL_TRUE) {
- log_error("Failed to compile shader %s!\n", filename);
-
- GLint info_length = 0;
- glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &info_length);
- if (info_length > 1) {
- char *log = xmalloc((unsigned)info_length * sizeof(*log));
- glGetShaderInfoLog(shader, info_length, NULL, log);
- log_error("\t%s\n", log);
- free(log);
- }
- exit(EXIT_FAILURE);
- }
-}
-
-GLuint create_shader_program(const char *vert, const char *frag)
-{
- GLuint vertex_shader = glCreateShader(GL_VERTEX_SHADER);
- load_shader(vertex_shader, vert);
-
- GLuint fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
- load_shader(fragment_shader, frag);
-
- GLuint shader = glCreateProgram();
- glAttachShader(shader, vertex_shader);
- glAttachShader(shader, fragment_shader);
- glLinkProgram(shader);
- glDetachShader(shader, fragment_shader);
- glDetachShader(shader, vertex_shader);
- glDeleteShader(fragment_shader);
- glDeleteShader(vertex_shader);
- return shader;
-}
-
-void GLAPIENTRY MessageCallback(
- GLenum source,
- GLenum type,
- GLuint id,
- GLenum severity,
- GLsizei length,
- const GLchar* message,
- const void* userParam)
-{
- log_debug("Message from OpenGL:\n");
- log_debug("\tSource: %s\n", gl_debug_source_string(source));
- log_debug("\tType: %s\n", gl_debug_type_string(type));
- log_debug("\tSeverity: %s\n", gl_debug_severity_string(severity));
- log_debug("\tMessage: %s\n", message);
-}
-
-const char *gl_debug_source_string(GLenum type)
-{
- switch(type) {
- case GL_DEBUG_SOURCE_API:
- return "API";
- case GL_DEBUG_SOURCE_WINDOW_SYSTEM:
- return "Window system";
- case GL_DEBUG_SOURCE_SHADER_COMPILER:
- return "Shader compiler";
- case GL_DEBUG_SOURCE_THIRD_PARTY:
- return "Third party";
- case GL_DEBUG_SOURCE_APPLICATION:
- return "Application";
- case GL_DEBUG_SOURCE_OTHER:
- return "Other";
- }
- return "unknown";
-}
-
-const char *gl_debug_type_string(GLenum type)
-{
- switch(type) {
- case GL_DEBUG_TYPE_ERROR:
- return "Error";
- case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
- return "Deprecated behavior";
- case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
- return "Undefined behavior";
- case GL_DEBUG_TYPE_PORTABILITY:
- return "Portability";
- case GL_DEBUG_TYPE_PERFORMANCE:
- return "Performance";
- case GL_DEBUG_TYPE_MARKER:
- return "Marker";
- case GL_DEBUG_TYPE_PUSH_GROUP:
- return "Push group";
- case GL_DEBUG_TYPE_POP_GROUP:
- return "Pop group";
- case GL_DEBUG_TYPE_OTHER:
- return "Other";
- }
- return "Unknown";
-}
-
-const char *gl_debug_severity_string(GLenum type)
-{
- switch(type) {
- case GL_DEBUG_SEVERITY_HIGH:
- return "High";
- case GL_DEBUG_SEVERITY_MEDIUM:
- return "Medium";
- case GL_DEBUG_SEVERITY_LOW:
- return "Low";
- case GL_DEBUG_SEVERITY_NOTIFICATION:
- return "Notification";
- }
- return "Unknown";
-}
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