1 files changed, 24 insertions, 2 deletions

diff --git a/linden/indra/newview/llspatialpartition.cpp b/linden/indra/newview/llspatialpartition.cpp
index 31b537c..c1d5ff3 100644
--- a/linden/indra/newview/llspatialpartition.cpp
+++ b/linden/indra/newview/llspatialpartition.cpp
@@ -1302,7 +1302,11 @@ void LLSpatialGroup::doOcclusion(LLCamera* camera)
 {
         if (mSpatialPartition->isOcclusionEnabled() && LLPipeline::sUseOcclusion > 1)
         {
-                if (earlyFail(camera, this))
+                static LLCachedControl<BOOL> render_water_void_culling("RenderWaterVoidCulling", TRUE);
+                // Don't cull hole/edge water, unless RenderWaterVoidCulling is set and we have the GL_ARB_depth_clamp extension.
+                if ((mSpatialPartition->mDrawableType == LLPipeline::RENDER_TYPE_VOIDWATER &&
+                         !(render_water_void_culling && gGLManager.mHasDepthClamp)) ||
+                    earlyFail(camera, this))
                 {
                         setState(LLSpatialGroup::DISCARD_QUERY);
                         assert_states_valid(this);
@@ -1324,11 +1328,28 @@ void LLSpatialGroup::doOcclusion(LLCamera* camera)
                                         buildOcclusion();
                                 }
 
+                                // Depth clamp all water to avoid it being culled as a result of being
+                                // behind the far clip plane, and in the case of edge water to avoid
+                                // it being culled while still visible.
+                                bool const use_depth_clamp =
+                                        gGLManager.mHasDepthClamp &&
+                                        (mSpatialPartition->mDrawableType == LLPipeline::RENDER_TYPE_WATER ||
+                                         mSpatialPartition->mDrawableType == LLPipeline::RENDER_TYPE_VOIDWATER);
+                                if (use_depth_clamp)
+                                {
+                                        glEnable(GL_DEPTH_CLAMP);
+                                }
+
                                 glBeginQueryARB(GL_SAMPLES_PASSED_ARB, mOcclusionQuery);                                        
                                 glVertexPointer(3, GL_FLOAT, 0, mOcclusionVerts);
                                 glDrawRangeElements(GL_TRIANGLE_FAN, 0, 7, 8,
                                                         GL_UNSIGNED_BYTE, get_box_fan_indices(camera, mBounds[0]));
                                 glEndQueryARB(GL_SAMPLES_PASSED_ARB);
+
+                                if (use_depth_clamp)
+                                {
+                                        glDisable(GL_DEPTH_CLAMP);
+                                }
                         }
 
                         setState(LLSpatialGroup::QUERY_PENDING);
@@ -2280,9 +2301,10 @@ void renderBoundingBox(LLDrawable* drawable, BOOL set_color = TRUE)
                                                 gGL.color4f(0.5f,0.5f,0.5f,1.0f);
                                                 break;
                                 case LLViewerObject::LL_VO_PART_GROUP:
-                        case LLViewerObject::LL_VO_HUD_PART_GROUP:
+                                case LLViewerObject::LL_VO_HUD_PART_GROUP:
                                                 gGL.color4f(0,0,1,1);
                                                 break;
+                                case LLViewerObject::LL_VO_VOID_WATER:
                                 case LLViewerObject::LL_VO_WATER:
                                                 gGL.color4f(0,0.5f,1,1);
                                                 break;