cell rendering: provide normals where necessary to avoid rendering errors

ObjectTypes/VolumeMeshObject/VolumeMeshBufferManagerT_impl.hh

@@ -352,7 +352,9 @@ void VolumeMeshBufferManager<VolumeMesh>::setOptionsFromDrawMode(ACG::SceneGraph
     else if (_drawMode & (mDrawModes.facesFlatShaded | mDrawModes.facesTexturedShaded | mDrawModes.facesColoredPerFaceFlatShaded))
         enablePerFaceNormals();
     else if (_drawMode & (mDrawModes.cellsSmoothShaded | mDrawModes.facesSmoothShaded | mDrawModes.halffacesSmoothShaded |
-                          mDrawModes.cellsPhongShaded  | mDrawModes.facesPhongShaded  | mDrawModes.halffacesPhongShaded))
+                          mDrawModes.cellsPhongShaded  | mDrawModes.facesPhongShaded  | mDrawModes.halffacesPhongShaded |
+                          mDrawModes.cellsColoredPerCell | mDrawModes.cellsColoredPerFace | mDrawModes.cellsColoredPerHalfface |
+                          mDrawModes.cellsColoredPerVertex | mDrawModes.cellsTransparent))
         enablePerVertexNormals();
     else
         disableNormals();

ObjectTypes/VolumeMeshObject/VolumeMeshNodeT_impl.hh

@@ -757,7 +757,7 @@ void VolumeMeshNodeT<VolumeMeshT>::getCellRenderObjects(IRenderer* _renderer, GL
 
     ro.shaderDesc.clearTextures();
 
-    ro.shaderDesc.shadeMode = SG_SHADE_GOURAUD;
+    ro.shaderDesc.shadeMode = SG_SHADE_UNLIT;
 
     ro.depthRange = Vec2f(0.01f, 1.0f);