From adebc36bc7203052d766ea6bf775808169f84b62 Mon Sep 17 00:00:00 2001
From: Shyotl <Shyotl@gmail.com>
Date: Sat, 24 Nov 2012 01:00:25 -0600
Subject: [PATCH] Cheap workaround for osgrid giving us an invalid pure-white
 single-channel opaque water texture. First it purges the texture from the
 cache and attempts to refetch, and if it's still invalid it falls back to the
 transparent water texture (which won't actually be transparent due to
 blending being disabled). Also fixed some annoying console spam related to
 null textures, and also now using the correct glTexGen* function. More
 details in comments.

---
 indra/newview/lldrawpoolwater.cpp | 43 +++++++++++++++++++++++++++----
 1 file changed, 38 insertions(+), 5 deletions(-)

diff --git a/indra/newview/lldrawpoolwater.cpp b/indra/newview/lldrawpoolwater.cpp
index 371f979a0..701da9b2a 100644
--- a/indra/newview/lldrawpoolwater.cpp
+++ b/indra/newview/lldrawpoolwater.cpp
@@ -53,6 +53,8 @@
 #include "pipeline.h"
 #include "llviewershadermgr.h"
 #include "llwaterparammanager.h"
+#include "llappviewer.h"
+#include "lltexturecache.h"
 
 const LLUUID TRANSPARENT_WATER_TEXTURE("2bfd3884-7e27-69b9-ba3a-3e673f680004");
 const LLUUID OPAQUE_WATER_TEXTURE("43c32285-d658-1793-c123-bf86315de055");
@@ -260,8 +262,11 @@ void LLDrawPoolWater::render(S32 pass)
 		{
 			continue;
 		}
-		gGL.getTexUnit(0)->bind(face->getTexture());
-		face->renderIndexed();
+		if(face->getTexture() && face->getTexture()->hasGLTexture())
+		{
+			gGL.getTexUnit(0)->bind(face->getTexture());
+			face->renderIndexed();
+		}
 	}
 
 	// Now, disable texture coord generation on texture state 1
@@ -367,6 +372,34 @@ void LLDrawPoolWater::renderOpaqueLegacyWater()
 
 	gPipeline.disableLights();
 
+	//Singu note: This is a hack around bizarre opensim behavior. The opaque water texture we get is pure white and only has one channel.
+	// This behavior is clearly incorrect, so we try to detect that case, purge it from the cache, and try to re-fetch the texture.
+	// If the re-fetched texture is still invalid, or doesn't exist, we use transparent water, which is fine since alphablend is unset.
+	// The current logic for refetching is crude here, and probably wont work if, say, a prim were to also have the texture for some reason,
+	// however it works well enough otherwise, and is much cleaner than diving into LLTextureList, LLViewerFetchedTexture, and LLViewerTexture.
+	// Perhaps a proper reload mechanism could be done if we ever add user-level texture reloading, but until then it's not a huge priority.
+	// Failing to fully refetch will just give us the same invalid texture we started with, which will result in the fallback texture being used.
+	if(mOpaqueWaterImagep != mWaterImagep)
+	{
+		if(mOpaqueWaterImagep->isMissingAsset())
+		{
+			mOpaqueWaterImagep = mWaterImagep;
+		}
+		else if(mOpaqueWaterImagep->hasGLTexture() && mOpaqueWaterImagep->getComponents() < 3)
+		{
+			LLAppViewer::getTextureCache()->removeFromCache(mOpaqueWaterImagep->getID());
+			static bool sRefetch = true;
+			if(sRefetch)
+			{
+				sRefetch = false;
+				gTextureList.deleteImage(gTextureList.findImage( mOpaqueWaterImagep->getID() ));
+				mOpaqueWaterImagep = NULL;
+				mOpaqueWaterImagep = LLViewerTextureManager::getFetchedTexture(OPAQUE_WATER_TEXTURE);
+			}
+			else
+				mOpaqueWaterImagep = mWaterImagep;
+		}
+	}
 	mOpaqueWaterImagep->addTextureStats(1024.f*1024.f);
 
 	// Activate the texture binding and bind one
@@ -380,8 +413,8 @@ void LLDrawPoolWater::renderOpaqueLegacyWater()
 	{
 		glEnable(GL_TEXTURE_GEN_S); //texture unit 0
 		glEnable(GL_TEXTURE_GEN_T); //texture unit 0
-		glTexGenf(GL_S, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR);
-		glTexGenf(GL_T, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR);
+		glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR);
+		glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR);
 	}
 
 	// Use the fact that we know all water faces are the same size
@@ -674,7 +707,7 @@ void LLDrawPoolWater::shade()
 			}
 
 			LLVOWater* water = (LLVOWater*) face->getViewerObject();
-			if(diffTex > -1 && face->getTexture()->hasGLTexture())
+			if(diffTex > -1 && face->getTexture() && face->getTexture()->hasGLTexture())
 				gGL.getTexUnit(diffTex)->bind(face->getTexture());
 
 			sNeedsReflectionUpdate = TRUE;