Fix T48045: Freestyle ID user decrement error.

This fixes reported issue, but there could be more of those hidden in Freestyle code,
it did not handle user refcount at all (and the fact it by-passes BKE in some places
for efficiency does not help here).

Note that this should be relatively harmless, since freestyle uses own Main during
render, so everything is cleaned up in the end in any case... But better try to
handle IDs correctly here too. :)

1 files changed, 5 insertions, 0 deletions

diff --git a/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp b/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp
index 7c10591591c..5c361de8d8d 100644
--- a/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp
+++ b/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp
@@ -243,6 +243,8 @@ Material* BlenderStrokeRenderer::GetStrokeShader(Main *bmain, bNodeTree *iNodeTr
 	PointerRNA fromptr, toptr;
 	NodeShaderAttribute *storage;
 
+	id_us_min(&ma->id);
+
 	if (iNodeTree) {
 		// make a copy of linestyle->nodetree
 		ntree = ntreeCopyTree_ex(iNodeTree, bmain, do_id_user);
@@ -514,6 +516,8 @@ void BlenderStrokeRenderer::RenderStrokeRepBasic(StrokeRep *iStrokeRep) const
 			ma->mode |= MA_SHLESS;
 			ma->vcol_alpha = 1;
 
+			id_us_min(&ma->id);
+
 			// Textures
 			while (iStrokeRep->getMTex(a)) {
 				ma->mtex[a] = (MTex *)iStrokeRep->getMTex(a);
@@ -734,6 +738,7 @@ void BlenderStrokeRenderer::GenerateStrokeMesh(StrokeGroup *group, bool hasTex)
 	     it != itend; ++it)
 	{
 		mesh->mat[material_index] = (*it)->getMaterial();
+		id_us_plus(&mesh->mat[material_index]->id);
 
 		vector<Strip*>& strips = (*it)->getStrips();
 		for (vector<Strip*>::const_iterator s = strips.begin(), send = strips.end(); s != send; ++s) {