1 files changed, 53 insertions, 0 deletions
diff --git a/indra/newview/llspatialpartition.cpp b/indra/newview/llspatialpartition.cpp
index 42cd1133a2..3e801a47d7 100644
--- a/indra/newview/llspatialpartition.cpp
+++ b/indra/newview/llspatialpartition.cpp
@@ -237,6 +237,59 @@ BOOL LLSpatialGroup::updateInGroup(LLDrawable *drawablep, BOOL immediate)
 	return FALSE;
 }
 
+void LLSpatialGroup::expandExtents(const LLVector4a* addingExtents, const LLXformMatrix& currentTransform)
+{
+	// Get coordinates of the adding extents
+	const LLVector4a& min = addingExtents[0];
+	const LLVector4a& max = addingExtents[1];
+
+	// Get coordinates of all corners of the bounding box
+	LLVector3 corners[] =
+	{
+		LLVector3(min[0], min[1], min[2]),
+		LLVector3(min[0], min[1], max[2]),
+		LLVector3(min[0], max[1], min[2]),
+		LLVector3(min[0], max[1], max[2]),
+		LLVector3(max[0], min[1], min[2]),
+		LLVector3(max[0], min[1], max[2]),
+		LLVector3(max[0], max[1], min[2]),
+		LLVector3(max[0], max[1], max[2])
+	};
+
+	// New extents (to be expanded)
+	LLVector3 extents[] =
+	{
+		LLVector3(mExtents[0].getF32ptr()),
+		LLVector3(mExtents[1].getF32ptr())
+	};
+
+	LLQuaternion backwardRotation = ~currentTransform.getRotation();
+	for (LLVector3& corner : corners)
+	{
+		// Make coordinates relative to the current position
+		corner -= currentTransform.getPosition();
+		// Rotate coordinates backward to the current rotation
+		corner.rotVec(backwardRotation);
+		// Expand root extents on the current corner
+		for (int j = 0; j < 3; ++j)
+		{
+			if (corner[j] < extents[0][j])
+				extents[0][j] = corner[j];
+			if (corner[j] > extents[1][j])
+				extents[1][j] = corner[j];
+		}
+	}
+
+	// Set new expanded extents
+	mExtents[0].load3(extents[0].mV);
+	mExtents[1].load3(extents[1].mV);
+
+	// Calculate new center and size
+	mBounds[0].setAdd(mExtents[0], mExtents[1]);
+	mBounds[0].mul(0.5f);
+	mBounds[1].setSub(mExtents[0], mExtents[1]);
+	mBounds[1].mul(0.5f);
+}
 
 BOOL LLSpatialGroup::addObject(LLDrawable *drawablep)
 {