Ported Mesh Deform modifier

This modifier still has issues that are not related to this port:

- While editing the deformation mesh, the deformed mesh doesn't update.
  This update only happens after exiting edit mode, making editing
  cumbersome.
- Binding doesn't work yet. It works fine when binding in master and
  loading pre-bound in 2.8. This was also an issue before this port, and
  will be investigated separately.

1 files changed, 42 insertions, 38 deletions

diff --git a/source/blender/modifiers/intern/MOD_meshdeform.c b/source/blender/modifiers/intern/MOD_meshdeform.c
index 8b25d192f7f..de3c3d94ad0 100644
--- a/source/blender/modifiers/intern/MOD_meshdeform.c
+++ b/source/blender/modifiers/intern/MOD_meshdeform.c
@@ -32,6 +32,7 @@
  *  \ingroup modifiers
  */
 
+#include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
 #include "DNA_object_types.h"
 #include "DNA_scene_types.h"
@@ -40,9 +41,10 @@
 #include "BLI_task.h"
 #include "BLI_utildefines.h"
 
-#include "BKE_cdderivedmesh.h"
 #include "BKE_global.h"
+#include "BKE_library.h"
 #include "BKE_library_query.h"
+#include "BKE_mesh.h"
 #include "BKE_modifier.h"
 #include "BKE_deform.h"
 #include "BKE_editmesh.h"
@@ -273,17 +275,18 @@ static void meshdeform_vert_task(
 }
 
 static void meshdeformModifier_do(
-        ModifierData *md, struct Depsgraph *depsgraph, Object *ob, DerivedMesh *dm,
+        ModifierData *md, Object *ob, Mesh *mesh,
         float (*vertexCos)[3], int numVerts)
 {
 	MeshDeformModifierData *mmd = (MeshDeformModifierData *) md;
-	DerivedMesh *tmpdm, *cagedm;
+	Mesh *cagemesh;
 	MDeformVert *dvert = NULL;
 	float imat[4][4], cagemat[4][4], iobmat[4][4], icagemat[3][3], cmat[4][4];
 	float co[3], (*dco)[3], (*bindcagecos)[3];
 	int a, totvert, totcagevert, defgrp_index;
 	float (*cagecos)[3];
 	MeshdeformUserdata data;
+	bool free_cagemesh = false;
 
 	if (!mmd->object || (!mmd->bindcagecos && !mmd->bindfunc))
 		return;
@@ -299,23 +302,24 @@ static void meshdeformModifier_do(
 	 * We'll support this case once granular dependency graph is landed.
 	 */
 	if (mmd->object->mode & OB_MODE_EDIT) {
-		BMEditMesh *em = BKE_editmesh_from_object(mmd->object);
-		tmpdm = editbmesh_get_derived_cage_and_final(depsgraph, md->scene, mmd->object, em, 0, &cagedm);
-		if (tmpdm)
-			tmpdm->release(tmpdm);
+		/* TODO(Sybren): do we need to check the modifier mode in this case? */
+		/* TODO(Sybren): should we get from BMEditMesh *em = BKE_editmesh_from_object(mmd->object) instead? */
+		cagemesh = get_mesh_eval_for_modifier(ob, md->mode & eModifierMode_Render ? MOD_APPLY_RENDER : 0);
+	}
+	else {
+		cagemesh = get_mesh_eval_for_modifier(ob, md->mode & eModifierMode_Render ? MOD_APPLY_RENDER : 0);
 	}
-	else
-		cagedm = mmd->object->derivedFinal;
 
 	/* if we don't have one computed, use derivedmesh from data
 	 * without any modifiers */
-	if (!cagedm) {
-		cagedm = get_dm(mmd->object, NULL, NULL, NULL, false, false);
-		if (cagedm)
-			cagedm->needsFree = 1;
+	if (!cagemesh) {
+		cagemesh = get_mesh(mmd->object, NULL, NULL, NULL, false, false);
+		if (cagemesh) {
+			free_cagemesh = true;
+		}
 	}
 	
-	if (!cagedm) {
+	if (!cagemesh) {
 		modifier_setError(md, "Cannot get mesh from cage object");
 		return;
 	}
@@ -334,35 +338,33 @@ static void meshdeformModifier_do(
 		/* progress bar redraw can make this recursive .. */
 		if (!recursive) {
 			recursive = 1;
-			mmd->bindfunc(md->scene, mmd, cagedm, (float *)vertexCos, numVerts, cagemat);
+			mmd->bindfunc(md->scene, mmd, cagemesh, (float *)vertexCos, numVerts, cagemat);
 			recursive = 0;
 		}
 	}
 
 	/* verify we have compatible weights */
 	totvert = numVerts;
-	totcagevert = cagedm->getNumVerts(cagedm);
+	totcagevert = cagemesh->totvert;
 
 	if (mmd->totvert != totvert) {
 		modifier_setError(md, "Verts changed from %d to %d", mmd->totvert, totvert);
-		cagedm->release(cagedm);
+		if (free_cagemesh) BKE_id_free(NULL, cagemesh);
 		return;
 	}
 	else if (mmd->totcagevert != totcagevert) {
 		modifier_setError(md, "Cage verts changed from %d to %d", mmd->totcagevert, totcagevert);
-		cagedm->release(cagedm);
+		if (free_cagemesh) BKE_id_free(NULL, cagemesh);
 		return;
 	}
 	else if (mmd->bindcagecos == NULL) {
 		modifier_setError(md, "Bind data missing");
-		cagedm->release(cagedm);
+		if (free_cagemesh) BKE_id_free(NULL, cagemesh);
 		return;
 	}
 
-	cagecos = MEM_malloc_arrayN(totcagevert, sizeof(*cagecos), "meshdeformModifier vertCos");
-
 	/* setup deformation data */
-	cagedm->getVertCos(cagedm, cagecos);
+	cagecos = BKE_mesh_vertexCos_get(cagemesh, NULL);
 	bindcagecos = (float(*)[3])mmd->bindcagecos;
 
 	/* We allocate 1 element extra to make it possible to
@@ -383,7 +385,7 @@ static void meshdeformModifier_do(
 			copy_v3_v3(dco[a], co);
 	}
 
-	modifier_get_vgroup(ob, dm, mmd->defgrp_name, &dvert, &defgrp_index);
+	modifier_get_vgroup_mesh(ob, mesh, mmd->defgrp_name, &dvert, &defgrp_index);
 
 	/* Initialize data to be pass to the for body function. */
 	data.mmd = mmd;
@@ -406,36 +408,38 @@ static void meshdeformModifier_do(
 	/* release cage derivedmesh */
 	MEM_freeN(dco);
 	MEM_freeN(cagecos);
-	cagedm->release(cagedm);
+	if (free_cagemesh) BKE_id_free(NULL, cagemesh);
 }
 
 static void deformVerts(ModifierData *md, const ModifierEvalContext *ctx,
-                        DerivedMesh *derivedData,
+                        Mesh *mesh,
                         float (*vertexCos)[3],
                         int numVerts)
 {
-	DerivedMesh *dm = get_dm(ctx->object, NULL, derivedData, NULL, false, false);
+	Mesh *mesh_src = get_mesh(ctx->object, NULL, mesh, NULL, false, false);
 
 	modifier_vgroup_cache(md, vertexCos); /* if next modifier needs original vertices */
 
-	meshdeformModifier_do(md, ctx->depsgraph, ctx->object, dm, vertexCos, numVerts);
+	meshdeformModifier_do(md, ctx->object, mesh, vertexCos, numVerts);
 
-	if (dm && dm != derivedData)
-		dm->release(dm);
+	if (mesh_src && mesh_src != mesh) {
+		BKE_id_free(NULL, mesh_src);
+	}
 }
 
 static void deformVertsEM(ModifierData *md, const ModifierEvalContext *ctx,
                           struct BMEditMesh *UNUSED(editData),
-                          DerivedMesh *derivedData,
+                          Mesh *mesh,
                           float (*vertexCos)[3],
                           int numVerts)
 {
-	DerivedMesh *dm = get_dm(ctx->object, NULL, derivedData, NULL, false, false);
+	Mesh *mesh_src = get_mesh(ctx->object, NULL, mesh, NULL, false, false);
 
-	meshdeformModifier_do(md, ctx->depsgraph, ctx->object, dm, vertexCos, numVerts);
+	meshdeformModifier_do(md, ctx->object, mesh, vertexCos, numVerts);
 
-	if (dm && dm != derivedData)
-		dm->release(dm);
+	if (mesh_src && mesh_src != mesh) {
+		BKE_id_free(NULL, mesh_src);
+	}
 }
 
 #define MESHDEFORM_MIN_INFLUENCE 0.00001f
@@ -512,16 +516,16 @@ ModifierTypeInfo modifierType_MeshDeform = {
 
 	/* copyData */          copyData,
 
-	/* deformVerts_DM */    deformVerts,
+	/* deformVerts_DM */    NULL,
 	/* deformMatrices_DM */ NULL,
-	/* deformVertsEM_DM */  deformVertsEM,
+	/* deformVertsEM_DM */  NULL,
 	/* deformMatricesEM_DM*/NULL,
 	/* applyModifier_DM */  NULL,
 	/* applyModifierEM_DM */NULL,
 
-	/* deformVerts */       NULL,
+	/* deformVerts */       deformVerts,
 	/* deformMatrices */    NULL,
-	/* deformVertsEM */     NULL,
+	/* deformVertsEM */     deformVertsEM,
 	/* deformMatricesEM */  NULL,
 	/* applyModifier */     NULL,
 	/* applyModifierEM */   NULL,