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diff --git a/subprojects/nk_pugl/pugl/examples/shader_utils.h b/subprojects/nk_pugl/pugl/examples/shader_utils.h
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+/*
+ Copyright 2019 David Robillard <http://drobilla.net>
+
+ Permission to use, copy, modify, and/or distribute this software for any
+ purpose with or without fee is hereby granted, provided that the above
+ copyright notice and this permission notice appear in all copies.
+
+ THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "glad/glad.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef struct
+{
+ GLuint vertexShader;
+ GLuint fragmentShader;
+ GLuint program;
+} Program;
+
+static GLuint
+compileShader(const char* source, const GLenum type)
+{
+ GLuint shader = glCreateShader(type);
+ const int sourceLength = (int)strlen(source);
+ glShaderSource(shader, 1, &source, &sourceLength);
+ glCompileShader(shader);
+
+ int status;
+ glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
+ if (status == GL_FALSE) {
+ GLint length;
+ glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &length);
+
+ char* log = (char*)calloc(1, (size_t)length);
+ glGetShaderInfoLog(shader, length, &length, log);
+ fprintf(stderr, "error: Failed to compile shader (%s)\n", log);
+ free(log);
+
+ return 0;
+ }
+
+ return shader;
+}
+
+static void
+deleteProgram(Program program)
+{
+ glDeleteShader(program.vertexShader);
+ glDeleteShader(program.fragmentShader);
+ glDeleteProgram(program.program);
+}
+
+static Program
+compileProgram(const char* vertexSource, const char* fragmentSource)
+{
+ static const Program nullProgram = {0, 0, 0};
+
+ Program program = {compileShader(vertexSource, GL_VERTEX_SHADER),
+ compileShader(fragmentSource, GL_FRAGMENT_SHADER),
+ glCreateProgram()};
+
+ if (!program.vertexShader || !program.fragmentShader || !program.program) {
+ deleteProgram(program);
+ return nullProgram;
+ }
+
+ glAttachShader(program.program, program.vertexShader);
+ glAttachShader(program.program, program.fragmentShader);
+ glLinkProgram(program.program);
+
+ GLint status;
+ glGetProgramiv(program.program, GL_LINK_STATUS, &status);
+ if (status == GL_FALSE) {
+ GLint length;
+ glGetProgramiv(program.program, GL_INFO_LOG_LENGTH, &length);
+
+ char* log = (char*)calloc(1, (size_t)length);
+ glGetProgramInfoLog(program.program, length, &length, &log[0]);
+ fprintf(stderr, "error: Failed to link program (%s)\n", log);
+ free(log);
+
+ deleteProgram(program);
+ return nullProgram;
+ }
+
+ return program;
+}