From 27a82684df128955f6c4e1467935be14ff9bb816 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Mon, 22 Feb 2010 17:04:14 +0000
Subject: [PATCH] Don't call glGetError between glBegin and glEnd

---
 source/glwrap.c       | 51 +++++++++++++++++++++++++++++++++++++++++--
 source/glwrap.funcs.t |  2 ++
 2 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/source/glwrap.c b/source/glwrap.c
index bf05214..6835114 100644
--- a/source/glwrap.c
+++ b/source/glwrap.c
@@ -160,32 +160,79 @@ static inline void send_packet()
 	writev(fd, iovecs, cur_vec-iovecs);
 }
 
+int in_begin_block = 0;
 GLenum cur_error = GL_NO_ERROR;
 
 static void check_error()
 {
 	GLenum (*orig_glGetError)() = 0;
 	GLenum code;
+
+	if(in_begin_block)
+		return;
+
 	if(!orig_glGetError)
 		orig_glGetError = glsym("glGetError");
+
 	code = orig_glGetError();
 	if(code!=GL_NO_ERROR)
 	{
 		begin_packet(FUNC_GLDERROR);
 		write_int(code);
 		send_packet();
+
 		if(cur_error==GL_NO_ERROR)
 			cur_error = code;
 	}
 }
 
+void APIENTRY glBegin(GLenum mode)
+{
+	static void (*orig)(GLenum);
+	if(!orig)
+		orig = glsym("glBegin");
+	orig(mode);
+
+	begin_packet(FUNC_GLBEGIN);
+	write_int(mode);
+	send_packet();
+
+	in_begin_block = 1;
+}
+
+void APIENTRY glEnd()
+{
+	static void (*orig)();
+	if(!orig)
+		orig = glsym("glEnd");
+	orig();
+
+	begin_packet(FUNC_GLEND);
+	send_packet();
+
+	in_begin_block = 0;
+	check_error();
+}
+
 GLenum APIENTRY glGetError()
 {
-	GLenum ret = cur_error;
-	cur_error = GL_NO_ERROR;
+	GLenum ret = GL_NO_ERROR;
+
+	if(in_begin_block)
+	{
+		if(cur_error==GL_NO_ERROR)
+			cur_error = GL_INVALID_OPERATION;
+	}
+	else
+	{
+		ret = cur_error;
+		cur_error = GL_NO_ERROR;
+	}
+
 	begin_packet(FUNC_GLGETERROR);
 	write_int(ret);
 	send_packet();
+
 	return ret;
 }
 
diff --git a/source/glwrap.funcs.t b/source/glwrap.funcs.t
index 547d53f..eb77b0a 100644
--- a/source/glwrap.funcs.t
+++ b/source/glwrap.funcs.t
@@ -1,4 +1,6 @@
 # $Id$
+!handcode glBegin
+!handcode glEnd
 !handcode glGetError
 !handcode glXGetProcAddress
 !handcode glXGetProcAddressARB
-- 
2.43.0