Refactor CDData masks, to have one mask per mesh elem type.

We already have different storages for cddata of verts, edges etc.,
'simply' do the same for the mask flags we use all around Blender code
to request some data, or limit some operation to some layers, etc.

Reason we need this is that some cddata types (like Normals) are
actually shared between verts/polys/loops, and we don’t want to generate
clnors everytime we request vnors!

As a side note, this also does final fix to T59338, which was the
trigger for this patch (need to request computed loop normals for
another mesh than evaluated one).

Reviewers: brecht, campbellbarton, sergey

Differential Revision: https://developer.blender.org/D4407

1 files changed, 5 insertions, 7 deletions

diff --git a/source/blender/modifiers/intern/MOD_weightvgproximity.c b/source/blender/modifiers/intern/MOD_weightvgproximity.c
index 8df4b1df780..2e2e4fe963d 100644
--- a/source/blender/modifiers/intern/MOD_weightvgproximity.c
+++ b/source/blender/modifiers/intern/MOD_weightvgproximity.c
@@ -288,21 +288,19 @@ static void initData(ModifierData *md)
 	wmd->max_dist             = 1.0f; /* vert arbitrary distance, but don't use 0 */
 }
 
-static CustomDataMask requiredDataMask(Object *UNUSED(ob), ModifierData *md)
+static void requiredDataMask(Object *UNUSED(ob), ModifierData *md, CustomData_MeshMasks *r_cddata_masks)
 {
 	WeightVGProximityModifierData *wmd = (WeightVGProximityModifierData *) md;
-	CustomDataMask dataMask = 0;
 
 	/* We need vertex groups! */
-	dataMask |= CD_MASK_MDEFORMVERT;
+	r_cddata_masks->vmask |= CD_MASK_MDEFORMVERT;
 
 	/* Ask for UV coordinates if we need them. */
-	if (wmd->mask_tex_mapping == MOD_DISP_MAP_UV)
-		dataMask |= CD_MASK_MTFACE;
+	if (wmd->mask_tex_mapping == MOD_DISP_MAP_UV) {
+		r_cddata_masks->fmask |= CD_MASK_MTFACE;
+	}
 
 	/* No need to ask for CD_PREVIEW_MLOOPCOL... */
-
-	return dataMask;
 }
 
 static bool dependsOnTime(ModifierData *md)