From dc4219418b6d44180d5b467189262d79d0b99d14 Mon Sep 17 00:00:00 2001
From: divverent <divverent@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Tue, 6 Sep 2011 17:26:51 +0000
Subject: [PATCH] DDS support: convert DXT3/DXT5 to DXT1 when requesting
 non-alpha (correctness)

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11327 d7cf8633-e32d-0410-b094-e92efae38249
---
 gl_textures.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/gl_textures.c b/gl_textures.c
index 180447ff..3a5b20fc 100644
--- a/gl_textures.c
+++ b/gl_textures.c
@@ -2199,6 +2199,18 @@ rtexture_t *R_LoadTextureDDSFile(rtexturepool_t *rtexturepool, const char *filen
 		return NULL;
 	}
 
+	// when requesting a non-alpha texture and we have DXT3/5, convert to DXT1
+	if(!(flags & TEXF_ALPHA) && (textype == TEXTYPE_DXT3 || textype == TEXTYPE_DXT5))
+	{
+		textype = TEXTYPE_DXT1;
+		bytesperblock = 8;
+		ddssize -= 128;
+		ddssize /= 2;
+		for (i = 0;i < ddssize;i += bytesperblock)
+			memcpy(&ddspixels[i], &ddspixels[(i<<1)+8], 8);
+		ddssize += 128;
+	}
+
 	force_swdecode = false;
 	if(bytesperblock)
 	{
-- 
2.39.2