Freestyle: View map caching.

New render layer option named "View map cache" is added to reuse a
previously computed view map for subsequent rendering.  The cache is
automatically updated when the mesh geometry of the input 3D scene has
been changed.

This functionality offers a major performance boost for Freestyle
animation rendering when camera-space mesh geometry is static, as well
as for repeated still renders with updates of line stylization options.

Although the "View map cache" toggle is a render layer option, the cache
memory is shared by all render layers and scenes.  This means that if
Freestyle is used for two or more render layers (possibly in different
scenes through the compositor), then the cached view map for one render
layer is replaced by a new view map for another render layer and hence
no performance gain is expected.

1 files changed, 1 insertions, 0 deletions

diff --git a/source/blender/freestyle/FRS_freestyle.h b/source/blender/freestyle/FRS_freestyle.h
index fc9fc35e410..1815883bf0d 100644
--- a/source/blender/freestyle/FRS_freestyle.h
+++ b/source/blender/freestyle/FRS_freestyle.h
@@ -48,6 +48,7 @@ int FRS_is_freestyle_enabled(struct SceneRenderLayer *srl);
 void FRS_init_stroke_rendering(struct Render *re);
 struct Render *FRS_do_stroke_rendering(struct Render *re, struct SceneRenderLayer *srl, int render);
 void FRS_finish_stroke_rendering(struct Render *re);
+void FRS_free_view_map_cache();
 void FRS_composite_result(struct Render *re, struct SceneRenderLayer *srl, struct Render *freestyle_render);
 void FRS_exit(void);