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

4 files changed, 40 insertions, 4 deletions

diff --git a/indra/llrender/llgl.cpp b/indra/llrender/llgl.cpp
index f29ee0e57e..a460912e70 100644
--- a/indra/llrender/llgl.cpp
+++ b/indra/llrender/llgl.cpp
@@ -328,6 +328,7 @@ LLGLManager::LLGLManager() :
 	mHasShaderObjects(FALSE),
 	mHasVertexShader(FALSE),
 	mHasFragmentShader(FALSE),
+	mNumTextureImageUnits(0),
 	mHasOcclusionQuery(FALSE),
 	mHasOcclusionQuery2(FALSE),
 	mHasPointParameters(FALSE),
@@ -534,6 +535,13 @@ bool LLGLManager::initGL()
 		return false;
 	}
 	
+	if (mHasFragmentShader)
+	{
+		GLint num_tex_image_units;
+		glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS_ARB, &num_tex_image_units);
+		mNumTextureImageUnits = num_tex_image_units;
+	}
+	
 	setToDebugGPU();
 
 	initGLStates();
@@ -878,11 +886,13 @@ void LLGLManager::initExtensions()
 		LL_INFOS("RenderInit") << "Disabling mip-map generation for Intel GPUs" << LL_ENDL;
 		mHasMipMapGeneration = FALSE;
 	}
+#if !LL_DARWIN
 	if (mIsATI && mHasMipMapGeneration)
 	{
 		LL_INFOS("RenderInit") << "Disabling mip-map generation for ATI GPUs (performance opt)" << LL_ENDL;
 		mHasMipMapGeneration = FALSE;
 	}
+#endif
 	
 	// Misc
 	glGetIntegerv(GL_MAX_ELEMENTS_VERTICES, (GLint*) &mGLMaxVertexRange);
diff --git a/indra/llrender/llgl.h b/indra/llrender/llgl.h
index 3d002fd8c4..1d7ab188fc 100644
--- a/indra/llrender/llgl.h
+++ b/indra/llrender/llgl.h
@@ -91,6 +91,7 @@ public:
 	BOOL mHasShaderObjects;
 	BOOL mHasVertexShader;
 	BOOL mHasFragmentShader;
+	S32  mNumTextureImageUnits;
 	BOOL mHasOcclusionQuery;
 	BOOL mHasOcclusionQuery2;
 	BOOL mHasPointParameters;
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;
 	}
 }
diff --git a/indra/llrender/llrendertarget.cpp b/indra/llrender/llrendertarget.cpp
index cd2556d435..da1e94df64 100644
--- a/indra/llrender/llrendertarget.cpp
+++ b/indra/llrender/llrendertarget.cpp
@@ -44,6 +44,7 @@ void check_framebuffer_status()
 		case GL_FRAMEBUFFER_COMPLETE:
 			break;
 		default:
+			llwarns << "check_framebuffer_status failed -- " << std::hex << status << llendl;
 			ll_fail("check_framebuffer_status failed");	
 			break;
 		}