From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 12 Dec 2015 11:16:17 +0000 (+0200)
Subject: Move shader program linking to a separate function
X-Git-Url: http://git.tdb.fi/?p=geometrycompositor.git;a=commitdiff_plain;h=7726f59d95180e7fcb985dd94b3815749e102069

Move shader program linking to a separate function
---

diff --git a/source/main.c b/source/main.c
index 731323f..0992542 100644
--- a/source/main.c
+++ b/source/main.c
@@ -181,12 +181,36 @@ unsigned compile_shader(GLenum type, const char *source)
 	return shader;
 }
 
-int create_gl_resources(Compositor *compositor, CompositedScreen *screen)
+unsigned link_program(unsigned *shaders, unsigned nshaders)
 {
+	unsigned program;
+	unsigned i;
 	int status;
 	char info_log[1024];
 	GLsizei length;
 
+	program = glCreateProgram();
+	for(i=0; i<nshaders; ++i)
+		glAttachShader(program, shaders[i]);
+	glBindAttribLocation(program, 0, "vertex");
+	glLinkProgram(program);
+
+	glGetProgramiv(program, GL_LINK_STATUS, &status);
+	glGetProgramInfoLog(program, sizeof(info_log), &length, info_log);
+	if(!status)
+	{
+		fprintf(stderr, "Program link failed:\n%s\n", info_log);
+		glDeleteProgram(program);
+		return 0;
+	}
+	else if(length)
+		printf("Program info log:\n%s\n", info_log);
+
+	return program;
+}
+
+int create_gl_resources(Compositor *compositor, CompositedScreen *screen)
+{
 	use_gl(compositor, screen);
 
 	screen->shaders[0] = compile_shader(GL_VERTEX_SHADER, vshader);
@@ -194,25 +218,12 @@ int create_gl_resources(Compositor *compositor, CompositedScreen *screen)
 	if(!screen->shaders[0] || !screen->shaders[1])
 		return 0;
 
-	screen->program = glCreateProgram();
-	glAttachShader(screen->program, screen->shaders[0]);
-	glAttachShader(screen->program, screen->shaders[1]);
-	glBindAttribLocation(screen->program, 0, "vertex");
-	glLinkProgram(screen->program);
+	screen->program = link_program(screen->shaders, 2);
+	if(!screen->program)
+		return 0;
 
 	screen->geometry_loc = glGetUniformLocation(screen->program, "geometry");
 
-	glGetProgramiv(screen->program, GL_LINK_STATUS, &status);
-	glGetProgramInfoLog(screen->program, sizeof(info_log), &length, info_log);
-	if(!status)
-	{
-		fprintf(stderr, "Program link failed:\n%s\n", info_log);
-		glDeleteProgram(screen->program);
-		return 0;
-	}
-	else if(length)
-		printf("Program info log:\n%s\n", info_log);
-
 	glGenBuffers(1, &screen->vertex_buffer);
 	glBindBuffer(GL_ARRAY_BUFFER, screen->vertex_buffer);
 	glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);