Add an option to mesh.calc_tessface() to get rid of polygons and loops

The purpose of this change is to add extra possibility to render engines and
export scripts to reduce peak memory footprint during their operation.

This new argument should be used with care since it'll leave mesh in not really
compatible with blender format, but it's ok to be used on temp meshes.

Unfortunately, it's hard to get scene where it'll show huge benefit because
in my tests with cycles peak memory is reached in MEM_printmemlist_stats().

However, in the file with sintel dragon it gives around 1gig of memory benefit
after removing the polys which would allow other heavy to compute stuff such as
hair (or even pointiness calculation) to not be a peak memory usage.

In any case, this change is nice to have IMO, and only means more parts of
scene export code should be optimized memory-wise.

Reviewers: campbellbarton

Differential Revision: https://developer.blender.org/D1125

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/editors/include/ED_mesh.h b/source/blender/editors/include/ED_mesh.h
index 8eb7fdf0c40..ccf97221112 100644
--- a/source/blender/editors/include/ED_mesh.h
+++ b/source/blender/editors/include/ED_mesh.h
@@ -256,7 +256,7 @@ void ED_mesh_faces_remove(struct Mesh *mesh, struct ReportList *reports, int cou
 void ED_mesh_edges_remove(struct Mesh *mesh, struct ReportList *reports, int count);
 void ED_mesh_vertices_remove(struct Mesh *mesh, struct ReportList *reports, int count);
 
-void ED_mesh_calc_tessface(struct Mesh *mesh);
+void ED_mesh_calc_tessface(struct Mesh *mesh, bool free_mpoly);
 void ED_mesh_update(struct Mesh *mesh, struct bContext *C, int calc_edges, int calc_tessface);
 
 void ED_mesh_uv_texture_ensure(struct Mesh *me, const char *name);