Modifier stack: move vgroup editing modifiers to new Mesh-based system.

Some notes here:
* Proximity with non-mesh objects (like curve, see TEST_2 scene in
weightvg testfile) are not working currently. This is known TODO of COW
depsgraph project.
* Proximity modifier is slower, due to some other TODO pending on
BVHTree creation/caching for Mesh.

1 files changed, 48 insertions, 27 deletions

diff --git a/source/blender/modifiers/intern/MOD_weightvgedit.c b/source/blender/modifiers/intern/MOD_weightvgedit.c
index 1a9651909dd..cc000cbee09 100644
--- a/source/blender/modifiers/intern/MOD_weightvgedit.c
+++ b/source/blender/modifiers/intern/MOD_weightvgedit.c
@@ -34,11 +34,11 @@
 #include "BLI_rand.h"
 
 #include "DNA_color_types.h"      /* CurveMapping. */
+#include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
 #include "DNA_modifier_types.h"
 #include "DNA_object_types.h"
 
-#include "BKE_cdderivedmesh.h"
 #include "BKE_colortools.h"       /* CurveMapping. */
 #include "BKE_deform.h"
 #include "BKE_library.h"
@@ -154,19 +154,18 @@ static bool isDisabled(ModifierData *md, int UNUSED(useRenderParams))
 	return (wmd->defgrp_name[0] == '\0');
 }
 
-static DerivedMesh *applyModifier(ModifierData *md,
+static Mesh *applyModifier(ModifierData *md,
                                   const ModifierEvalContext *ctx,
-                                  DerivedMesh *derivedData)
+                                  Mesh *mesh)
 {
 	WeightVGEditModifierData *wmd = (WeightVGEditModifierData *) md;
-	DerivedMesh *dm = derivedData;
+
 	MDeformVert *dvert = NULL;
 	MDeformWeight **dw = NULL;
 	float *org_w; /* Array original weights. */
 	float *new_w; /* Array new weights. */
-	int numVerts;
-	int defgrp_index;
 	int i;
+
 	/* Flags. */
 	const bool do_add  = (wmd->edit_flags & MOD_WVG_EDIT_ADD2VG) != 0;
 	const bool do_rem  = (wmd->edit_flags & MOD_WVG_EDIT_REMFVG) != 0;
@@ -176,30 +175,50 @@ static DerivedMesh *applyModifier(ModifierData *md,
 #endif
 
 	/* Get number of verts. */
-	numVerts = dm->getNumVerts(dm);
+	const int numVerts = mesh->totvert;
 
 	/* Check if we can just return the original mesh.
 	 * Must have verts and therefore verts assigned to vgroups to do anything useful!
 	 */
-	if ((numVerts == 0) || BLI_listbase_is_empty(&ctx->object->defbase))
-		return dm;
+	if ((numVerts == 0) || BLI_listbase_is_empty(&ctx->object->defbase)) {
+		return mesh;
+	}
 
 	/* Get vgroup idx from its name. */
-	defgrp_index = defgroup_name_index(ctx->object, wmd->defgrp_name);
-	if (defgrp_index == -1)
-		return dm;
+	const int defgrp_index = defgroup_name_index(ctx->object, wmd->defgrp_name);
+	if (defgrp_index == -1) {
+		return mesh;
+	}
 
-	dvert = CustomData_duplicate_referenced_layer(&dm->vertData, CD_MDEFORMVERT, numVerts);
+	const bool has_mdef = CustomData_has_layer(&mesh->vdata, CD_MDEFORMVERT);
 	/* If no vertices were ever added to an object's vgroup, dvert might be NULL. */
-	if (!dvert) {
+	if (!has_mdef) {
 		/* If this modifier is not allowed to add vertices, just return. */
-		if (!do_add)
-			return dm;
-		/* Else, add a valid data layer! */
-		dvert = CustomData_add_layer(&dm->vertData, CD_MDEFORMVERT, CD_CALLOC, NULL, numVerts);
-		/* Ultimate security check. */
-		if (!dvert)
-			return dm;
+		if (!do_add) {
+			return mesh;
+		}
+	}
+
+	Mesh *result;
+	BKE_id_copy_ex(
+	            NULL, &mesh->id, (ID **)&result,
+	            LIB_ID_CREATE_NO_MAIN |
+	            LIB_ID_CREATE_NO_USER_REFCOUNT |
+	            LIB_ID_CREATE_NO_DEG_TAG|
+	            LIB_ID_COPY_NO_PREVIEW,
+	            false);
+
+	if (has_mdef) {
+		dvert = CustomData_get_layer(&result->vdata, CD_MDEFORMVERT);
+	}
+	else {
+		/* Add a valid data layer! */
+		dvert = CustomData_add_layer(&result->vdata, CD_MDEFORMVERT, CD_CALLOC, NULL, numVerts);
+	}
+	/* Ultimate security check. */
+	if (!dvert) {
+		BKE_id_free(NULL, result);
+		return mesh;
 	}
 
 	/* Get org weights, assuming 0.0 for vertices not in given vgroup. */
@@ -220,17 +239,19 @@ static DerivedMesh *applyModifier(ModifierData *md,
 	if (wmd->falloff_type != MOD_WVG_MAPPING_NONE) {
 		RNG *rng = NULL;
 
-		if (wmd->falloff_type == MOD_WVG_MAPPING_RANDOM)
+		if (wmd->falloff_type == MOD_WVG_MAPPING_RANDOM) {
 			rng = BLI_rng_new_srandom(BLI_ghashutil_strhash(ctx->object->id.name + 2));
+		}
 
 		weightvg_do_map(numVerts, new_w, wmd->falloff_type, wmd->cmap_curve, rng);
 
-		if (rng)
+		if (rng) {
 			BLI_rng_free(rng);
+		}
 	}
 
 	/* Do masking. */
-	weightvg_do_mask(numVerts, NULL, org_w, new_w, ctx->object, dm, wmd->mask_constant,
+	weightvg_do_mask(numVerts, NULL, org_w, new_w, ctx->object, result, wmd->mask_constant,
 	                 wmd->mask_defgrp_name, wmd->modifier.scene, wmd->mask_texture,
 	                 wmd->mask_tex_use_channel, wmd->mask_tex_mapping,
 	                 wmd->mask_tex_map_obj, wmd->mask_tex_uvlayer_name);
@@ -251,7 +272,7 @@ static DerivedMesh *applyModifier(ModifierData *md,
 	MEM_freeN(dw);
 
 	/* Return the vgroup-modified mesh. */
-	return dm;
+	return result;
 }
 
 
@@ -271,14 +292,14 @@ ModifierTypeInfo modifierType_WeightVGEdit = {
 	/* deformMatrices_DM */ NULL,
 	/* deformVertsEM_DM */  NULL,
 	/* deformMatricesEM_DM*/NULL,
-	/* applyModifier_DM */  applyModifier,
+	/* applyModifier_DM */  NULL,
 	/* applyModifierEM_DM */NULL,
 
 	/* deformVerts */       NULL,
 	/* deformMatrices */    NULL,
 	/* deformVertsEM */     NULL,
 	/* deformMatricesEM */  NULL,
-	/* applyModifier */     NULL,
+	/* applyModifier */     applyModifier,
 	/* applyModifierEM */   NULL,
 
 	/* initData */          initData,