Patch removes unused includes of gl.hrl which in turn was moved to the
wxErlang.

--- esdl-1.2.orig/src/sdl_img.erl
+++ esdl-1.2/src/sdl_img.erl
@@ -16,7 +16,6 @@
 -module(sdl_img).
 
 -include("sdl_img_funcs.hrl").
--include("gl.hrl").
 -include("sdl_util.hrl").
 -include("sdl_video.hrl").
 
--- esdl-1.2.orig/src/sdl_ttf.erl
+++ esdl-1.2/src/sdl_ttf.erl
@@ -16,7 +16,6 @@
 
 -include("sdl_ttf.hrl").
 -include("sdl_ttf_funcs.hrl").
--include("gl.hrl").
 -include("sdl_util.hrl").
 -include("sdl_video.hrl").