From d512d1dc9857e3c2bbfa0a7b5856bdf420412b8f Mon Sep 17 00:00:00 2001
From: Per Inge Mathisen <per.mathisen@gmail.com>
Date: Wed, 1 Jul 2015 20:30:01 +0200
Subject: [PATCH] 3.1: Remove hack to support some pre-OpenGL-2.0 systems that
 made assumptions about internals in GLEW that breaks with GLEW 1.12.

See ticket:4300 reported by pabs
---
 lib/ivis_opengl/screen.cpp | 61 --------------------------------------
 lib/ivis_opengl/screen.h   |  1 -
 src/init.cpp               |  3 --
 3 files changed, 65 deletions(-)

diff --git a/lib/ivis_opengl/screen.cpp b/lib/ivis_opengl/screen.cpp
index 3135a830a82..11d048a178c 100644
--- a/lib/ivis_opengl/screen.cpp
+++ b/lib/ivis_opengl/screen.cpp
@@ -175,7 +175,6 @@ bool screenInitialise()
 
 	if (canRunShaders)
 	{
-		screen_EnableMissingFunctions();  // We need to do this before pie_LoadShaders(), but the effect of this call will be undone later by iV_TextInit(), so we will need to call it again.
 		if (pie_LoadShaders())
 		{
 			pie_SetShaderAvailability(true);
@@ -218,66 +217,6 @@ bool screen_IsVBOAvailable()
 	return GLEW_VERSION_1_5 || GLEW_ARB_vertex_buffer_object;
 }
 
-// Make OpenGL's VBO functions available under the core names for drivers that support OpenGL 1.4 only but have the VBO extension
-void screen_EnableMissingFunctions()
-{
-	if (!GLEW_VERSION_1_3 && GLEW_ARB_multitexture)
-	{
-		debug(LOG_WARNING, "Pre-OpenGL 1.3: Fixing ARB_multitexture extension function names.");
-
-		__glewActiveTexture = __glewActiveTextureARB;
-		__glewMultiTexCoord2fv = __glewMultiTexCoord2fvARB;
-	}
-
-	if (!GLEW_VERSION_1_5 && GLEW_ARB_vertex_buffer_object)
-	{
-		debug(LOG_WARNING, "Pre-OpenGL 1.5: Fixing ARB_vertex_buffer_object extension function names.");
-
-		__glewBindBuffer = __glewBindBufferARB;
-		__glewBufferData = __glewBufferDataARB;
-		__glewBufferSubData = __glewBufferSubDataARB;
-		__glewDeleteBuffers = __glewDeleteBuffersARB;
-		__glewGenBuffers = __glewGenBuffersARB;
-		__glewGetBufferParameteriv = __glewGetBufferParameterivARB;
-		__glewGetBufferPointerv = __glewGetBufferPointervARB;
-		__glewGetBufferSubData = __glewGetBufferSubDataARB;
-		__glewIsBuffer = __glewIsBufferARB;
-		__glewMapBuffer = __glewMapBufferARB;
-		__glewUnmapBuffer = __glewUnmapBufferARB;
-	}
-
-	if (!GLEW_VERSION_2_0 && GLEW_ARB_shader_objects)
-	{
-		debug(LOG_WARNING, "Pre-OpenGL 2.0: Fixing ARB_shader_objects extension function names.");
-
-		__glewGetUniformLocation = __glewGetUniformLocationARB;
-		__glewAttachShader = __glewAttachObjectARB;
-		__glewCompileShader = __glewCompileShaderARB;
-		__glewCreateProgram = __glewCreateProgramObjectARB;
-		__glewCreateShader = __glewCreateShaderObjectARB;
-		__glewGetProgramInfoLog = __glewGetInfoLogARB;
-		__glewGetShaderInfoLog = __glewGetInfoLogARB;  // Same as previous.
-		__glewGetProgramiv = __glewGetObjectParameterivARB;
-		__glewUseProgram = __glewUseProgramObjectARB;
-		__glewGetShaderiv = __glewGetObjectParameterivARB;
-		__glewLinkProgram = __glewLinkProgramARB;
-		__glewShaderSource = __glewShaderSourceARB;
-		__glewUniform1f = __glewUniform1fARB;
-		__glewUniform1i = __glewUniform1iARB;
-		__glewUniform4fv = __glewUniform4fvARB;
-	}
-
-	if ((GLEW_ARB_imaging || GLEW_EXT_blend_color) && __glewBlendColor == NULL)
-	{
-		__glewBlendColor = __glewBlendColorEXT;  // Shouldn't be needed if GLEW_ARB_imaging is true, but apparently is needed even in that case, with some drivers..?
-		if (__glewBlendColor == NULL)
-		{
-			debug(LOG_ERROR, "Your graphics driver is broken, and claims to support ARB_imaging or EXT_blend_color without exporting glBlendColor[EXT].");
-			__GLEW_ARB_imaging = __GLEW_EXT_blend_color = 0;
-		}
-	}
-}
-
 void screen_SetBackDropFromFile(const char *filename)
 {
 	// HACK : We should use a resource handler here!
diff --git a/lib/ivis_opengl/screen.h b/lib/ivis_opengl/screen.h
index efd3e346cc3..68e442d110f 100644
--- a/lib/ivis_opengl/screen.h
+++ b/lib/ivis_opengl/screen.h
@@ -63,7 +63,6 @@ extern void screenDoDumpToDiskIfRequired(void);
 void screen_enableMapPreview(char *name, int width, int height, Vector2i *playerpositions);
 void screen_disableMapPreview(void);
 bool screen_getMapPreview(void);
-void screen_EnableMissingFunctions();
 
 bool screen_IsVBOAvailable();
 struct OPENGL_DATA
diff --git a/src/init.cpp b/src/init.cpp
index a157f8126d0..b1d8527f268 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -716,9 +716,6 @@ bool systemInitialise(void)
 	// Initialize the iVis text rendering module
 	iV_TextInit();
 
-	// Fix badly named OpenGL functions. Must be done after iV_TextInit, to avoid the renames being clobbered by an extra glewInit() call.
-	screen_EnableMissingFunctions();
-
 	iV_Reset();								// Reset the IV library.
 
 	return true;