OpenSubdiv: Fix crash happening when disabling Use OpenSubdiv option

The issue was caused by the changes from this morning.

3 files changed, 23 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/CCGSubSurf.h b/source/blender/blenkernel/intern/CCGSubSurf.h
index 23f7e71a311..1649cec1e3d 100644
--- a/source/blender/blenkernel/intern/CCGSubSurf.h
+++ b/source/blender/blenkernel/intern/CCGSubSurf.h
@@ -234,6 +234,8 @@ void ccgSubSurf_evaluatorFVarUV(CCGSubSurf *ss,
                                 float grid_u, float grid_v,
                                 float uv[2]);
 
+void ccgSubSurf_free_osd_mesh(CCGSubSurf *ss);
+
 #endif
 
 #endif  /* __CCGSUBSURF_H__ */
diff --git a/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c b/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c
index c7526521963..81f9ea6dc16 100644
--- a/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c
+++ b/source/blender/blenkernel/intern/CCGSubSurf_opensubdiv.c
@@ -863,4 +863,17 @@ void ccgSubSurf__sync_opensubdiv(CCGSubSurf *ss)
 #endif
 }
 
+void ccgSubSurf_free_osd_mesh(CCGSubSurf *ss)
+{
+	if (ss->osd_mesh != NULL) {
+		/* TODO(sergey): Make sure free happens form the main thread! */
+		openSubdiv_deleteOsdGLMesh(ss->osd_mesh);
+		ss->osd_mesh = NULL;
+	}
+	if (ss->osd_vao != 0) {
+		glDeleteVertexArrays(1, &ss->osd_vao);
+		ss->osd_vao = 0;
+	}
+}
+
 #endif  /* WITH_OPENSUBDIV */
diff --git a/source/blender/blenkernel/intern/scene.c b/source/blender/blenkernel/intern/scene.c
index 19c2ff10901..e2687246820 100644
--- a/source/blender/blenkernel/intern/scene.c
+++ b/source/blender/blenkernel/intern/scene.c
@@ -1573,6 +1573,14 @@ static void scene_free_unused_opensubdiv_cache(Scene *scene)
 			if (md != NULL && md->type == eModifierType_Subsurf) {
 				SubsurfModifierData *smd = (SubsurfModifierData *) md;
 				bool object_in_editmode = object->mode == OB_MODE_EDIT;
+				if (!smd->use_opensubdiv) {
+					if (smd->mCache != NULL) {
+						ccgSubSurf_free_osd_mesh(smd->mCache);
+					}
+					if (smd->emCache != NULL) {
+						ccgSubSurf_free_osd_mesh(smd->emCache);
+					}
+				}
 				if (object_in_editmode && smd->mCache != NULL) {
 					ccgSubSurf_free(smd->mCache);
 					smd->mCache = NULL;