make EDBM_index_arrays's stay in memory, blender was allocating an array and filling it for verts/edges/faces on every redraw.

this may introduce bugs which I didn't catch, but they are very easy to identify in a debug build which has asserts to ensure the arrays are valid before use.

in my own test drawing ~98,304 quads - this gave an overall ~16% drawing speedup.

3 files changed, 6 insertions, 14 deletions

diff --git a/source/blender/editors/space_view3d/drawobject.c b/source/blender/editors/space_view3d/drawobject.c
index 75fe1e27bf5..780b7426d51 100644
--- a/source/blender/editors/space_view3d/drawobject.c
+++ b/source/blender/editors/space_view3d/drawobject.c
@@ -2838,7 +2838,7 @@ static void draw_em_fancy(Scene *scene, View3D *v3d, RegionView3D *rv3d,
 		}
 	}
 	
-	EDBM_index_arrays_init(em, BM_VERT | BM_EDGE | BM_FACE);
+	EDBM_index_arrays_ensure(em, BM_VERT | BM_EDGE | BM_FACE);
 
 	if (dt > OB_WIRE) {
 		if (check_object_draw_texture(scene, v3d, dt)) {
@@ -2989,8 +2989,6 @@ static void draw_em_fancy(Scene *scene, View3D *v3d, RegionView3D *rv3d,
 		bglPolygonOffset(rv3d->dist, 0.0);
 		GPU_disable_material();
 	}
-
-	EDBM_index_arrays_free(em);
 }
 
 /* Mesh drawing routines */
@@ -7123,7 +7121,7 @@ void draw_object_backbufsel(Scene *scene, View3D *v3d, RegionView3D *rv3d, Objec
 
 				DerivedMesh *dm = editbmesh_get_derived_cage(scene, ob, em, CD_MASK_BAREMESH);
 
-				EDBM_index_arrays_init(em, BM_VERT | BM_EDGE | BM_FACE);
+				EDBM_index_arrays_ensure(em, BM_VERT | BM_EDGE | BM_FACE);
 
 				bbs_mesh_solid_EM(em, scene, v3d, ob, dm, ts->selectmode & SCE_SELECT_FACE);
 				if (ts->selectmode & SCE_SELECT_FACE)
@@ -7149,8 +7147,6 @@ void draw_object_backbufsel(Scene *scene, View3D *v3d, RegionView3D *rv3d, Objec
 				bglPolygonOffset(rv3d->dist, 0.0);
 
 				dm->release(dm);
-
-				EDBM_index_arrays_free(em);
 			}
 			else {
 				Mesh *me = ob->data;
diff --git a/source/blender/editors/space_view3d/view3d_iterators.c b/source/blender/editors/space_view3d/view3d_iterators.c
index 04d47e6cf5d..a0b36e57d69 100644
--- a/source/blender/editors/space_view3d/view3d_iterators.c
+++ b/source/blender/editors/space_view3d/view3d_iterators.c
@@ -113,9 +113,8 @@ void mesh_foreachScreenVert(
 		ED_view3d_clipping_local(vc->rv3d, vc->obedit->obmat);  /* for local clipping lookups */
 	}
 
-	EDBM_index_arrays_init(vc->em, BM_VERT);
+	EDBM_index_arrays_ensure(vc->em, BM_VERT);
 	dm->foreachMappedVert(dm, mesh_foreachScreenVert__mapFunc, &data);
-	EDBM_index_arrays_free(vc->em);
 
 	dm->release(dm);
 }
@@ -172,9 +171,8 @@ void mesh_foreachScreenEdge(
 		ED_view3d_clipping_local(vc->rv3d, vc->obedit->obmat);  /* for local clipping lookups */
 	}
 
-	EDBM_index_arrays_init(vc->em, BM_EDGE);
+	EDBM_index_arrays_ensure(vc->em, BM_EDGE);
 	dm->foreachMappedEdge(dm, mesh_foreachScreenEdge__mapFunc, &data);
-	EDBM_index_arrays_free(vc->em);
 
 	dm->release(dm);
 }
@@ -209,9 +207,8 @@ void mesh_foreachScreenFace(
 
 	ED_view3d_init_mats_rv3d(vc->obedit, vc->rv3d);
 
-	EDBM_index_arrays_init(vc->em, BM_FACE);
+	EDBM_index_arrays_ensure(vc->em, BM_FACE);
 	dm->foreachMappedFaceCenter(dm, mesh_foreachScreenFace__mapFunc, &data);
-	EDBM_index_arrays_free(vc->em);
 
 	dm->release(dm);
 }
diff --git a/source/blender/editors/space_view3d/view3d_snap.c b/source/blender/editors/space_view3d/view3d_snap.c
index e60eed42770..f570ec38ae3 100644
--- a/source/blender/editors/space_view3d/view3d_snap.c
+++ b/source/blender/editors/space_view3d/view3d_snap.c
@@ -340,9 +340,8 @@ static void make_trans_verts(Object *obedit, float min[3], float max[3], int mod
 		}
 		
 		if (transvmain && em->derivedCage) {
-			EDBM_index_arrays_init(em, BM_VERT);
+			EDBM_index_arrays_ensure(em, BM_VERT);
 			em->derivedCage->foreachMappedVert(em->derivedCage, set_mapped_co, userdata);
-			EDBM_index_arrays_free(em);
 		}
 	}
 	else if (obedit->type == OB_ARMATURE) {