Fix transform snap code using 'allocated' flags to get verts/edges/etc. arrays again from DM.

This was... horribly wrong, CDDM will often *not* need to allocate
anything to return arrays of mesh items! Just check whether array
pointer is NULL.

Also, remove `DM_get_looptri_array`, that one is useless currently,
`dm->getLoopTriArray` will always return cached array (computing it if
needed).

5 files changed, 12 insertions, 74 deletions

diff --git a/source/blender/blenkernel/BKE_DerivedMesh.h b/source/blender/blenkernel/BKE_DerivedMesh.h
index 63ff1149a68..a31a51f9402 100644
--- a/source/blender/blenkernel/BKE_DerivedMesh.h
+++ b/source/blender/blenkernel/BKE_DerivedMesh.h
@@ -832,11 +832,5 @@ struct MEdge *DM_get_edge_array(struct DerivedMesh *dm, bool *r_allocated);
 struct MLoop *DM_get_loop_array(struct DerivedMesh *dm, bool *r_allocated);
 struct MPoly *DM_get_poly_array(struct DerivedMesh *dm, bool *r_allocated);
 struct MFace *DM_get_tessface_array(struct DerivedMesh *dm, bool *r_allocated);
-const MLoopTri *DM_get_looptri_array(
-        DerivedMesh *dm,
-        const MVert *mvert,
-        const MPoly *mpoly, int mpoly_len,
-        const MLoop *mloop, int mloop_len,
-        bool *r_allocated);
 
 #endif  /* __BKE_DERIVEDMESH_H__ */
diff --git a/source/blender/blenkernel/intern/DerivedMesh.c b/source/blender/blenkernel/intern/DerivedMesh.c
index 9e33dd56b00..17e805cef70 100644
--- a/source/blender/blenkernel/intern/DerivedMesh.c
+++ b/source/blender/blenkernel/intern/DerivedMesh.c
@@ -4399,35 +4399,3 @@ MFace *DM_get_tessface_array(DerivedMesh *dm, bool *r_allocated)
 
 	return mface;
 }
-
-const MLoopTri *DM_get_looptri_array(
-        DerivedMesh *dm,
-        const MVert *mvert,
-        const MPoly *mpoly, int mpoly_len,
-        const MLoop *mloop, int mloop_len,
-        bool *r_allocated)
-{
-	const MLoopTri *looptri = dm->getLoopTriArray(dm);
-	*r_allocated = false;
-
-	if (looptri == NULL) {
-		if (mpoly_len > 0) {
-			const int looptris_num = poly_to_tri_count(mpoly_len, mloop_len);
-			MLoopTri *looptri_data;
-
-			looptri_data = MEM_mallocN(sizeof(MLoopTri) * looptris_num, __func__);
-
-			BKE_mesh_recalc_looptri(
-			        mloop, mpoly,
-			        mvert,
-			        mloop_len, mpoly_len,
-			        looptri_data);
-
-			looptri = looptri_data;
-
-			*r_allocated = true;
-		}
-	}
-
-	return looptri;
-}
diff --git a/source/blender/blenkernel/intern/bvhutils.c b/source/blender/blenkernel/intern/bvhutils.c
index c1fad4f80c8..775499304d4 100644
--- a/source/blender/blenkernel/intern/bvhutils.c
+++ b/source/blender/blenkernel/intern/bvhutils.c
@@ -1137,7 +1137,6 @@ BVHTree *bvhtree_from_mesh_looptri(
 	const MLoopTri *looptri = NULL;
 	bool vert_allocated = false;
 	bool loop_allocated = false;
-	bool looptri_allocated = false;
 
 	BLI_rw_mutex_lock(&cache_rwlock, THREAD_LOCK_READ);
 	tree = bvhcache_find(dm->bvhCache, BVHTREE_FROM_LOOPTRI);
@@ -1150,12 +1149,7 @@ BVHTree *bvhtree_from_mesh_looptri(
 	mpoly = DM_get_poly_array(dm, &poly_allocated);
 
 	mloop = DM_get_loop_array(dm, &loop_allocated);
-	looptri = DM_get_looptri_array(
-	        dm,
-	        mvert,
-	        mpoly, dm->getNumPolys(dm),
-	        mloop, dm->getNumLoops(dm),
-	        &looptri_allocated);
+	looptri = dm->getLoopTriArray(dm);
 
 	if (poly_allocated) {
 		MEM_freeN(mpoly);
@@ -1193,7 +1187,7 @@ BVHTree *bvhtree_from_mesh_looptri(
 		        data, tree, true, epsilon,
 		        mvert, vert_allocated,
 		        mloop, loop_allocated,
-		        looptri, looptri_allocated);
+		        looptri, false);
 	}
 	else {
 		if (vert_allocated) {
@@ -1202,9 +1196,6 @@ BVHTree *bvhtree_from_mesh_looptri(
 		if (loop_allocated) {
 			MEM_freeN(mloop);
 		}
-		if (looptri_allocated) {
-			MEM_freeN((void *)looptri);
-		}
 		memset(data, 0, sizeof(*data));
 	}
 
diff --git a/source/blender/blenkernel/intern/mesh_remap.c b/source/blender/blenkernel/intern/mesh_remap.c
index c5fa9b15896..624898d47a5 100644
--- a/source/blender/blenkernel/intern/mesh_remap.c
+++ b/source/blender/blenkernel/intern/mesh_remap.c
@@ -1184,7 +1184,6 @@ void BKE_mesh_remap_calc_loops_from_dm(
 		bool polys_allocated_src;
 		MPoly *polys_src = DM_get_poly_array(dm_src, &polys_allocated_src);
 		const int num_polys_src = dm_src->getNumPolys(dm_src);
-		bool looptri_allocated_src = false;
 		const MLoopTri *looptri_src = NULL;
 		int num_looptri_src = 0;
 
@@ -1379,12 +1378,7 @@ void BKE_mesh_remap_calc_loops_from_dm(
 					dm_src->dirty |= dirty_tess_flag;
 				}
 
-				looptri_src = DM_get_looptri_array(
-				        dm_src,
-				        verts_src,
-				        polys_src, num_polys_src,
-				        loops_src, num_loops_src,
-				        &looptri_allocated_src);
+				looptri_src = dm_src->getLoopTriArray(dm_src);
 				num_looptri_src = dm_src->getNumLoopTri(dm_src);
 				looptri_active = BLI_BITMAP_NEW((size_t)num_looptri_src, __func__);
 
@@ -1403,7 +1397,7 @@ void BKE_mesh_remap_calc_loops_from_dm(
 					        &treedata[tindex],
 					        verts_src, verts_allocated_src,
 					        loops_src, loops_allocated_src,
-					        looptri_src, num_looptri_src, looptri_allocated_src,
+					        looptri_src, num_looptri_src, false,
 					        looptri_active, num_looptri_active, bvh_epsilon, 2, 6);
 					if (verts_allocated_src) {
 						verts_allocated_src = false;  /* Only 'give' our verts once, to first tree! */
@@ -1411,9 +1405,6 @@ void BKE_mesh_remap_calc_loops_from_dm(
 					if (loops_allocated_src) {
 						loops_allocated_src = false;  /* Only 'give' our loops once, to first tree! */
 					}
-					if (looptri_allocated_src) {
-						looptri_allocated_src = false;  /* Only 'give' our looptri once, to first tree! */
-					}
 				}
 
 				MEM_freeN(looptri_active);
@@ -1928,9 +1919,6 @@ void BKE_mesh_remap_calc_loops_from_dm(
 		if (polys_allocated_src) {
 			MEM_freeN(polys_src);
 		}
-		if (looptri_allocated_src) {
-			MEM_freeN((void *)looptri_src);
-		}
 		if (vert_to_loop_map_src) {
 			MEM_freeN(vert_to_loop_map_src);
 		}
diff --git a/source/blender/editors/transform/transform_snap_object.c b/source/blender/editors/transform/transform_snap_object.c
index 0fe121252be..fff92a8385a 100644
--- a/source/blender/editors/transform/transform_snap_object.c
+++ b/source/blender/editors/transform/transform_snap_object.c
@@ -436,21 +436,18 @@ static bool raycastDerivedMesh(
 				free_bvhtree_from_mesh(treedata);
 			}
 			else {
-				if (!treedata->vert_allocated) {
+				if (treedata->vert == NULL) {
 					treedata->vert = DM_get_vert_array(dm, &treedata->vert_allocated);
 				}
-				if (!treedata->loop_allocated) {
+				if (treedata->loop == NULL) {
 					treedata->loop = DM_get_loop_array(dm, &treedata->loop_allocated);
 				}
-				if (!treedata->looptri_allocated) {
-					if (!sod->poly_allocated) {
+				if (treedata->looptri == NULL) {
+					if (sod->mpoly == NULL) {
 						sod->mpoly = DM_get_poly_array(dm, &sod->poly_allocated);
 					}
-					treedata->looptri = DM_get_looptri_array(
-					        dm, treedata->vert,
-					        sod->mpoly, dm->getNumPolys(dm),
-					        treedata->loop, dm->getNumLoops(dm),
-					        &treedata->looptri_allocated);
+					treedata->looptri = dm->getLoopTriArray(dm);
+					treedata->looptri_allocated = false;
 				}
 			}
 		}
@@ -1709,10 +1706,10 @@ static bool snapDerivedMesh(
 				free_bvhtree_from_mesh(treedata);
 			}
 			else {
-				if (!treedata->vert_allocated) {
+				if (treedata->vert == NULL) {
 					treedata->vert = DM_get_vert_array(dm, &treedata->vert_allocated);
 				}
-				if ((tree_index == 1) && !treedata->edge_allocated) {
+				if ((tree_index == 1) && (treedata->edge == NULL)) {
 					treedata->edge = DM_get_edge_array(dm, &treedata->edge_allocated);
 				}
 			}