SH-1618 FIX -- Lighting and shadows crash ATI macs

* Fixed ATI mac "lighting and shadows" related crash
* Fixed up numerous GL errors on macs related to multiple color formats,
  the use of glEnable/glDisable on textures above the texture unit count
  and old ATI-specific code that was not appropriate for Mac.
* Disabled SSAO for ATI macs due to it not working with shadows
* Ongoing work to properly get shadows and SSAO functioning on ATI macs is required.

Reviewed by davep

1 files changed, 28 insertions, 4 deletions

diff --git a/indra/llrender/llrender.cpp b/indra/llrender/llrender.cpp
index 49e10c4790..c37139ac4c 100644
--- a/indra/llrender/llrender.cpp
+++ b/indra/llrender/llrender.cpp
@@ -119,14 +119,29 @@ void LLTexUnit::refreshState(void)
 	gGL.flush();
 	
 	glActiveTextureARB(GL_TEXTURE0_ARB + mIndex);
+
+	//
+	// Per apple spec, don't call glEnable/glDisable when index exceeds max texture units
+	// http://www.mailinglistarchive.com/html/mac-opengl@lists.apple.com/2008-07/msg00653.html
+	//
+	bool enableDisable = (mIndex < gGLManager.mNumTextureUnits);
+		
 	if (mCurrTexType != TT_NONE)
 	{
-		glEnable(sGLTextureType[mCurrTexType]);
+		if (enableDisable)
+		{
+			glEnable(sGLTextureType[mCurrTexType]);
+		}
+		
 		glBindTexture(sGLTextureType[mCurrTexType], mCurrTexture);
 	}
 	else
 	{
-		glDisable(GL_TEXTURE_2D);
+		if (enableDisable)
+		{
+			glDisable(GL_TEXTURE_2D);
+		}
+		
 		glBindTexture(GL_TEXTURE_2D, 0);	
 	}
 
@@ -167,7 +182,11 @@ void LLTexUnit::enable(eTextureType type)
 		mCurrTexType = type;
 
 		gGL.flush();
-		glEnable(sGLTextureType[type]);
+		
+		if (mIndex < gGLManager.mNumTextureUnits)
+		{
+			glEnable(sGLTextureType[type]);
+		}
 	}
 }
 
@@ -180,7 +199,12 @@ void LLTexUnit::disable(void)
 		activate();
 		unbind(mCurrTexType);
 		gGL.flush();
-		glDisable(sGLTextureType[mCurrTexType]);
+		
+		if (mIndex < gGLManager.mNumTextureUnits)
+		{
+			glDisable(sGLTextureType[mCurrTexType]);
+		}
+		
 		mCurrTexType = TT_NONE;
 	}
 }