SH-1802 Fix for disappearing meshes under some circuimstances.

1 files changed, 15 insertions, 7 deletions

diff --git a/indra/llmath/llvolume.cpp b/indra/llmath/llvolume.cpp
index 379ef4b344..8c81f27784 100644
--- a/indra/llmath/llvolume.cpp
+++ b/indra/llmath/llvolume.cpp
@@ -2642,14 +2642,20 @@ bool LLVolume::unpackVolumeFaces(std::istream& is, S32 size)
 			LLVector4a& min = face.mExtents[0];
 			LLVector4a& max = face.mExtents[1];
 
-			min.clear();
-			max.clear();
-			min = max = face.mPositions[0];
-
-			for (S32 i = 1; i < face.mNumVertices; ++i)
+			if (face.mNumVertices < 3)
+			{ //empty face, use a dummy 1cm (at 1m scale) bounding box
+				min.splat(-0.005f);
+				max.splat(0.005f);
+			}
+			else
 			{
-				min.setMin(min, face.mPositions[i]);
-				max.setMax(max, face.mPositions[i]);
+				min = max = face.mPositions[0];
+
+				for (S32 i = 1; i < face.mNumVertices; ++i)
+				{
+					min.setMin(min, face.mPositions[i]);
+					max.setMax(max, face.mPositions[i]);
+				}
 			}
 		}
 	}
@@ -5506,6 +5512,8 @@ LLVolumeFace::LLVolumeFace() :
 	mOctree(NULL)
 {
 	mExtents = (LLVector4a*) ll_aligned_malloc_16(sizeof(LLVector4a)*3);
+	mExtents[0].splat(-0.5f);
+	mExtents[1].splat(0.5f);
 	mCenter = mExtents+2;
 }