From 30a8a674ca821a8aafd08886de84933bce3803f7 Mon Sep 17 00:00:00 2001
From: Marrub <marrub@greyserv.net>
Date: Thu, 12 Nov 2015 07:12:27 +0000
Subject: [PATCH] various improvements

---
 main.c | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/main.c b/main.c
index c1f3254..5bc6a49 100644
--- a/main.c
+++ b/main.c
@@ -55,13 +55,35 @@ GLuint R_CreateShader(GLenum type, char const *src)
 	if(!success)
 	{
 		glGetShaderInfoLog(shader, 512, NULL, log);
-		printf("Shader compile failed: %s\n", log);
+		fprintf(stderr, "Shader compile failed!\n%s\n", log);
 		exit(1);
 	}
 
 	return shader;
 }
 
+GLuint R_LinkProgram(GLuint vertShader, GLuint fragShader)
+{
+	char log[512];
+	GLint success;
+	GLuint program;
+
+	program = glCreateProgram();
+	glAttachShader(program, vertShader);
+	glAttachShader(program, fragShader);
+	glLinkProgram(program);
+	glGetProgramiv(program, GL_LINK_STATUS, &success);
+
+	if(!success)
+	{
+		glGetProgramInfoLog(program, 512, NULL, log);
+		fprintf(stderr, "Failed to link shader program!\n%s\n", log);
+		exit(1);
+	}
+
+	return program;
+}
+
 char const *FXT_ReadFile(char const *fname)
 {
 	FILE *fp;
@@ -98,11 +120,7 @@ void R_InitGL()
 	// Init shaders.
 	re.VertShader = R_CreateShader(GL_VERTEX_SHADER, FXT_ReadFile("main.vp.glsl"));
 	re.FragShader = R_CreateShader(GL_FRAGMENT_SHADER, FXT_ReadFile("main.fp.glsl"));
-
-	re.Program = glCreateProgram();
-	glAttachShader(re.Program, re.VertShader);
-	glAttachShader(re.Program, re.FragShader);
-	glLinkProgram(re.Program);
+	re.Program = R_LinkProgram(re.VertShader, re.FragShader);
 
 	// Init uniform and attribute locations.