1 files changed, 70 insertions, 5 deletions

diff --git a/indra/newview/llfloatermodelpreview.cpp b/indra/newview/llfloatermodelpreview.cpp
index 73bf7f3e23..f0c580c8ee 100755
--- a/indra/newview/llfloatermodelpreview.cpp
+++ b/indra/newview/llfloatermodelpreview.cpp
@@ -738,6 +738,11 @@ void LLFloaterModelPreview::toggleGenarateNormals()
 {
 	bool enabled = childGetValue("gen_normals").asBoolean();
 	childSetEnabled("crease_angle", enabled);
+	if(enabled) {
+		mModelPreview->generateNormals();
+	} else {
+		mModelPreview->restoreNormals();
+	}
 }
 
 //static
@@ -3836,7 +3841,6 @@ void LLModelPreview::generateNormals()
 
 	S32 which_lod = mPreviewLOD;
 
-
 	if (which_lod > 4 || which_lod < 0 ||
 		mModel[which_lod].empty())
 	{
@@ -3851,18 +3855,79 @@ void LLModelPreview::generateNormals()
 
 	if (which_lod == 3 && !mBaseModel.empty())
 	{
-		for (LLModelLoader::model_list::iterator iter = mBaseModel.begin(); iter != mBaseModel.end(); ++iter)
+		if(mBaseModelFacesCopy.empty())
+		{
+			mBaseModelFacesCopy.reserve(mBaseModel.size());
+			for (LLModelLoader::model_list::iterator it = mBaseModel.begin(), itE = mBaseModel.end(); it != itE; ++it)
+			{
+				v_LLVolumeFace_t faces;
+				(*it)->copyFacesTo(faces);
+				mBaseModelFacesCopy.push_back(std::move(faces));
+			}
+		}
+
+		for (LLModelLoader::model_list::iterator it = mBaseModel.begin(), itE = mBaseModel.end(); it != itE; ++it)
 		{
-			(*iter)->generateNormals(angle_cutoff);
+			(*it)->generateNormals(angle_cutoff);
 		}
 
 		mVertexBuffer[5].clear();
 	}
 
-	for (LLModelLoader::model_list::iterator iter = mModel[which_lod].begin(); iter != mModel[which_lod].end(); ++iter)
+	bool perform_copy = mModelFacesCopy[which_lod].empty();
+	if(perform_copy) {
+		mModelFacesCopy[which_lod].reserve(mModel[which_lod].size());
+	}
+
+	for (LLModelLoader::model_list::iterator it = mModel[which_lod].begin(), itE = mModel[which_lod].end(); it != itE; ++it)
 	{
-		(*iter)->generateNormals(angle_cutoff);
+		if(perform_copy)
+		{
+			v_LLVolumeFace_t faces;
+			(*it)->copyFacesTo(faces);
+			mModelFacesCopy[which_lod].push_back(std::move(faces));
+		}
+
+		(*it)->generateNormals(angle_cutoff);
+	}
+
+	mVertexBuffer[which_lod].clear();
+	refresh();
+	updateStatusMessages();
+}
+
+void LLModelPreview::restoreNormals()
+{
+	S32 which_lod = mPreviewLOD;
+
+	if (which_lod > 4 || which_lod < 0 ||
+		mModel[which_lod].empty())
+	{
+		return;
+	}
+
+	if(!mBaseModelFacesCopy.empty())
+	{
+		llassert(mBaseModelFacesCopy.size() == mBaseModel.size());
+
+		vv_LLVolumeFace_t::const_iterator itF = mBaseModelFacesCopy.begin();
+		for (LLModelLoader::model_list::iterator it = mBaseModel.begin(), itE = mBaseModel.end(); it != itE; ++it, ++itF)
+		{
+			(*it)->copyFacesFrom((*itF));
+		}
+	}
+	mBaseModelFacesCopy.clear();
+
+
+	if(!mModelFacesCopy[which_lod].empty())
+	{
+		vv_LLVolumeFace_t::const_iterator itF = mModelFacesCopy[which_lod].begin();
+		for (LLModelLoader::model_list::iterator it = mModel[which_lod].begin(), itE = mModel[which_lod].end(); it != itE; ++it, ++itF)
+		{
+			(*it)->copyFacesFrom((*itF));
+		}
 	}
+	mModelFacesCopy[which_lod].clear();
 
 	mVertexBuffer[which_lod].clear();
 	refresh();