Multires: Remove legacy compatibility code

It was rather a huge chunk of code, which started to become
more harder to maintain with the transition to OpenSubdiv based
implementation. Because of this transition, the compatibility was
also rather on a poor side.

Remove compatibility support for pre-2.50.9 multires.

Ref T77107

Reviewed By: brecht, mont29

Differential Revision: https://developer.blender.org/D9238

7 files changed, 1 insertions, 857 deletions

diff --git a/source/blender/blenkernel/BKE_multires.h b/source/blender/blenkernel/BKE_multires.h
index fbdfc5b76a7..8ed3741c659 100644
--- a/source/blender/blenkernel/BKE_multires.h
+++ b/source/blender/blenkernel/BKE_multires.h
@@ -36,7 +36,6 @@ struct DerivedMesh;
 struct MDisps;
 struct Mesh;
 struct ModifierData;
-struct Multires;
 struct MultiresModifierData;
 struct Object;
 struct Scene;
@@ -125,11 +124,6 @@ void multiresModifier_sync_levels_ex(struct Object *ob_dst,
 
 void multires_stitch_grids(struct Object *);
 
-/* Related to the old multires */
-void multires_free(struct Multires *mr);
-void multires_load_old(struct Object *ob, struct Mesh *me);
-void multires_load_old_250(struct Mesh *);
-
 void multiresModifier_scale_disp(struct Depsgraph *depsgraph,
                                  struct Scene *scene,
                                  struct Object *ob);
diff --git a/source/blender/blenkernel/intern/mesh.c b/source/blender/blenkernel/intern/mesh.c
index 6ea83cf4330..97520654e7b 100644
--- a/source/blender/blenkernel/intern/mesh.c
+++ b/source/blender/blenkernel/intern/mesh.c
@@ -275,50 +275,6 @@ static void mesh_blend_read_data(BlendDataReader *reader, ID *id)
     mesh->totselect = 0;
   }
 
-  /* Multires data */
-  BLO_read_data_address(reader, &mesh->mr);
-  if (mesh->mr) {
-    BLO_read_list(reader, &mesh->mr->levels);
-    MultiresLevel *lvl = mesh->mr->levels.first;
-
-    CustomData_blend_read(reader, &mesh->mr->vdata, lvl->totvert);
-    BKE_defvert_blend_read(
-        reader, lvl->totvert, CustomData_get(&mesh->mr->vdata, 0, CD_MDEFORMVERT));
-    CustomData_blend_read(reader, &mesh->mr->fdata, lvl->totface);
-
-    BLO_read_data_address(reader, &mesh->mr->edge_flags);
-    BLO_read_data_address(reader, &mesh->mr->edge_creases);
-
-    BLO_read_data_address(reader, &mesh->mr->verts);
-
-    /* If mesh has the same number of vertices as the
-     * highest multires level, load the current mesh verts
-     * into multires and discard the old data. Needed
-     * because some saved files either do not have a verts
-     * array, or the verts array contains out-of-date
-     * data. */
-    if (mesh->totvert == ((MultiresLevel *)mesh->mr->levels.last)->totvert) {
-      if (mesh->mr->verts) {
-        MEM_freeN(mesh->mr->verts);
-      }
-      mesh->mr->verts = MEM_dupallocN(mesh->mvert);
-    }
-
-    for (; lvl; lvl = lvl->next) {
-      BLO_read_data_address(reader, &lvl->verts);
-      BLO_read_data_address(reader, &lvl->faces);
-      BLO_read_data_address(reader, &lvl->edges);
-      BLO_read_data_address(reader, &lvl->colfaces);
-    }
-  }
-
-  /* if multires is present but has no valid vertex data,
-   * there's no way to recover it; silently remove multires */
-  if (mesh->mr && !mesh->mr->verts) {
-    multires_free(mesh->mr);
-    mesh->mr = NULL;
-  }
-
   if ((BLO_read_requires_endian_switch(reader)) && mesh->tface) {
     TFace *tf = mesh->tface;
     for (int i = 0; i < mesh->totface; i++, tf++) {
diff --git a/source/blender/blenkernel/intern/multires.c b/source/blender/blenkernel/intern/multires.c
index 6e1168d8a16..bd9b1b24844 100644
--- a/source/blender/blenkernel/intern/multires.c
+++ b/source/blender/blenkernel/intern/multires.c
@@ -1449,9 +1449,6 @@ DerivedMesh *multires_make_derived_from_derived(
   return result;
 }
 
-/**** Old Multires code ****
- ***************************/
-
 /* Adapted from sculptmode.c */
 void old_mdisps_bilinear(float out[3], float (*disps)[3], const int st, float u, float v)
 {
@@ -1506,723 +1503,6 @@ void old_mdisps_bilinear(float out[3], float (*disps)[3], const int st, float u,
   add_v3_v3v3(out, d2[0], d2[1]);
 }
 
-static void old_mdisps_rotate(
-    int S, int UNUSED(newside), int oldside, int x, int y, float *u, float *v)
-{
-  float offset = oldside * 0.5f - 0.5f;
-
-  if (S == 1) {
-    *u = offset + x;
-    *v = offset - y;
-  }
-  if (S == 2) {
-    *u = offset + y;
-    *v = offset + x;
-  }
-  if (S == 3) {
-    *u = offset - x;
-    *v = offset + y;
-  }
-  if (S == 0) {
-    *u = offset - y;
-    *v = offset - x;
-  }
-}
-
-static void old_mdisps_convert(MFace *mface, MDisps *mdisp)
-{
-  int newlvl = log(sqrt(mdisp->totdisp) - 1) / M_LN2;
-  int oldlvl = newlvl + 1;
-  int oldside = multires_side_tot[oldlvl];
-  int newside = multires_side_tot[newlvl];
-  int nvert = (mface->v4) ? 4 : 3;
-  int newtotdisp = multires_grid_tot[newlvl] * nvert;
-  int x, y, S;
-  float(*disps)[3], (*out)[3], u = 0.0f, v = 0.0f; /* Quite gcc barking. */
-
-  disps = MEM_calloc_arrayN(newtotdisp, sizeof(float[3]), "multires disps");
-
-  out = disps;
-  for (S = 0; S < nvert; S++) {
-    for (y = 0; y < newside; y++) {
-      for (x = 0; x < newside; x++, out++) {
-        old_mdisps_rotate(S, newside, oldside, x, y, &u, &v);
-        old_mdisps_bilinear(*out, mdisp->disps, oldside, u, v);
-
-        if (S == 1) {
-          (*out)[1] = -(*out)[1];
-        }
-        else if (S == 2) {
-          SWAP(float, (*out)[0], (*out)[1]);
-        }
-        else if (S == 3) {
-          (*out)[0] = -(*out)[0];
-        }
-        else if (S == 0) {
-          SWAP(float, (*out)[0], (*out)[1]);
-          (*out)[0] = -(*out)[0];
-          (*out)[1] = -(*out)[1];
-        }
-      }
-    }
-  }
-
-  MEM_freeN(mdisp->disps);
-
-  mdisp->totdisp = newtotdisp;
-  mdisp->level = newlvl;
-  mdisp->disps = disps;
-}
-
-void multires_load_old_250(Mesh *me)
-{
-  MDisps *mdisps, *mdisps2;
-  MFace *mf;
-  int i, j, k;
-
-  mdisps = CustomData_get_layer(&me->fdata, CD_MDISPS);
-
-  if (mdisps) {
-    for (i = 0; i < me->totface; i++) {
-      if (mdisps[i].totdisp) {
-        old_mdisps_convert(&me->mface[i], &mdisps[i]);
-      }
-    }
-
-    CustomData_add_layer(&me->ldata, CD_MDISPS, CD_CALLOC, NULL, me->totloop);
-    mdisps2 = CustomData_get_layer(&me->ldata, CD_MDISPS);
-
-    k = 0;
-    mf = me->mface;
-    for (i = 0; i < me->totface; i++, mf++) {
-      int nvert = mf->v4 ? 4 : 3;
-      int totdisp = mdisps[i].totdisp / nvert;
-
-      for (j = 0; j < nvert; j++, k++) {
-        mdisps2[k].disps = MEM_calloc_arrayN(
-            totdisp, sizeof(float[3]), "multires disp in conversion");
-        mdisps2[k].totdisp = totdisp;
-        mdisps2[k].level = mdisps[i].level;
-        memcpy(mdisps2[k].disps, mdisps[i].disps + totdisp * j, totdisp);
-      }
-    }
-  }
-}
-
-/* Does not actually free lvl itself */
-static void multires_free_level(MultiresLevel *lvl)
-{
-  if (lvl) {
-    if (lvl->faces) {
-      MEM_freeN(lvl->faces);
-    }
-    if (lvl->edges) {
-      MEM_freeN(lvl->edges);
-    }
-    if (lvl->colfaces) {
-      MEM_freeN(lvl->colfaces);
-    }
-  }
-}
-
-void multires_free(Multires *mr)
-{
-  if (mr) {
-    MultiresLevel *lvl = mr->levels.first;
-
-    /* Free the first-level data */
-    if (lvl) {
-      CustomData_free(&mr->vdata, lvl->totvert);
-      CustomData_free(&mr->fdata, lvl->totface);
-      if (mr->edge_flags) {
-        MEM_freeN(mr->edge_flags);
-      }
-      if (mr->edge_creases) {
-        MEM_freeN(mr->edge_creases);
-      }
-    }
-
-    while (lvl) {
-      multires_free_level(lvl);
-      lvl = lvl->next;
-    }
-
-    /* mr->verts may be NULL when loading old files,
-     * see direct_link_mesh() in readfile.c, and T43560. */
-    MEM_SAFE_FREE(mr->verts);
-
-    BLI_freelistN(&mr->levels);
-
-    MEM_freeN(mr);
-  }
-}
-
-typedef struct IndexNode {
-  struct IndexNode *next, *prev;
-  int index;
-} IndexNode;
-
-static void create_old_vert_face_map(ListBase **map,
-                                     IndexNode **mem,
-                                     const MultiresFace *mface,
-                                     const int totvert,
-                                     const int totface)
-{
-  int i, j;
-  IndexNode *node = NULL;
-
-  (*map) = MEM_calloc_arrayN(totvert, sizeof(ListBase), "vert face map");
-  (*mem) = MEM_calloc_arrayN(totface, sizeof(IndexNode[4]), "vert face map mem");
-  node = *mem;
-
-  /* Find the users */
-  for (i = 0; i < totface; i++) {
-    for (j = 0; j < (mface[i].v[3] ? 4 : 3); j++, node++) {
-      node->index = i;
-      BLI_addtail(&(*map)[mface[i].v[j]], node);
-    }
-  }
-}
-
-static void create_old_vert_edge_map(ListBase **map,
-                                     IndexNode **mem,
-                                     const MultiresEdge *medge,
-                                     const int totvert,
-                                     const int totedge)
-{
-  int i, j;
-  IndexNode *node = NULL;
-
-  (*map) = MEM_calloc_arrayN(totvert, sizeof(ListBase), "vert edge map");
-  (*mem) = MEM_calloc_arrayN(totedge, sizeof(IndexNode[2]), "vert edge map mem");
-  node = *mem;
-
-  /* Find the users */
-  for (i = 0; i < totedge; i++) {
-    for (j = 0; j < 2; j++, node++) {
-      node->index = i;
-      BLI_addtail(&(*map)[medge[i].v[j]], node);
-    }
-  }
-}
-
-static MultiresFace *find_old_face(
-    ListBase *map, MultiresFace *faces, int v1, int v2, int v3, int v4)
-{
-  IndexNode *n1;
-  int v[4], i, j;
-
-  v[0] = v1;
-  v[1] = v2;
-  v[2] = v3;
-  v[3] = v4;
-
-  for (n1 = map[v1].first; n1; n1 = n1->next) {
-    int fnd[4] = {0, 0, 0, 0};
-
-    for (i = 0; i < 4; i++) {
-      for (j = 0; j < 4; j++) {
-        if (v[i] == faces[n1->index].v[j]) {
-          fnd[i] = 1;
-        }
-      }
-    }
-
-    if (fnd[0] && fnd[1] && fnd[2] && fnd[3]) {
-      return &faces[n1->index];
-    }
-  }
-
-  return NULL;
-}
-
-static MultiresEdge *find_old_edge(ListBase *map, MultiresEdge *edges, int v1, int v2)
-{
-  IndexNode *n1, *n2;
-
-  for (n1 = map[v1].first; n1; n1 = n1->next) {
-    for (n2 = map[v2].first; n2; n2 = n2->next) {
-      if (n1->index == n2->index) {
-        return &edges[n1->index];
-      }
-    }
-  }
-
-  return NULL;
-}
-
-static void multires_load_old_edges(
-    ListBase **emap, MultiresLevel *lvl, int *vvmap, int dst, int v1, int v2, int mov)
-{
-  int emid = find_old_edge(emap[2], lvl->edges, v1, v2)->mid;
-  vvmap[dst + mov] = emid;
-
-  if (lvl->next->next) {
-    multires_load_old_edges(emap + 1, lvl->next, vvmap, dst + mov, v1, emid, mov / 2);
-    multires_load_old_edges(emap + 1, lvl->next, vvmap, dst + mov, v2, emid, -mov / 2);
-  }
-}
-
-static void multires_load_old_faces(ListBase **fmap,
-                                    ListBase **emap,
-                                    MultiresLevel *lvl,
-                                    int *vvmap,
-                                    int dst,
-                                    int v1,
-                                    int v2,
-                                    int v3,
-                                    int v4,
-                                    int st2,
-                                    int st3)
-{
-  int fmid;
-  int emid13, emid14, emid23, emid24;
-
-  if (lvl && lvl->next) {
-    fmid = find_old_face(fmap[1], lvl->faces, v1, v2, v3, v4)->mid;
-    vvmap[dst] = fmid;
-
-    emid13 = find_old_edge(emap[1], lvl->edges, v1, v3)->mid;
-    emid14 = find_old_edge(emap[1], lvl->edges, v1, v4)->mid;
-    emid23 = find_old_edge(emap[1], lvl->edges, v2, v3)->mid;
-    emid24 = find_old_edge(emap[1], lvl->edges, v2, v4)->mid;
-
-    multires_load_old_faces(fmap + 1,
-                            emap + 1,
-                            lvl->next,
-                            vvmap,
-                            dst + st2 * st3 + st3,
-                            fmid,
-                            v2,
-                            emid23,
-                            emid24,
-                            st2,
-                            st3 / 2);
-
-    multires_load_old_faces(fmap + 1,
-                            emap + 1,
-                            lvl->next,
-                            vvmap,
-                            dst - st2 * st3 + st3,
-                            emid14,
-                            emid24,
-                            fmid,
-                            v4,
-                            st2,
-                            st3 / 2);
-
-    multires_load_old_faces(fmap + 1,
-                            emap + 1,
-                            lvl->next,
-                            vvmap,
-                            dst + st2 * st3 - st3,
-                            emid13,
-                            emid23,
-                            v3,
-                            fmid,
-                            st2,
-                            st3 / 2);
-
-    multires_load_old_faces(fmap + 1,
-                            emap + 1,
-                            lvl->next,
-                            vvmap,
-                            dst - st2 * st3 - st3,
-                            v1,
-                            fmid,
-                            emid13,
-                            emid14,
-                            st2,
-                            st3 / 2);
-
-    if (lvl->next->next) {
-      multires_load_old_edges(emap, lvl->next, vvmap, dst, emid24, fmid, st3);
-      multires_load_old_edges(emap, lvl->next, vvmap, dst, emid13, fmid, -st3);
-      multires_load_old_edges(emap, lvl->next, vvmap, dst, emid14, fmid, -st2 * st3);
-      multires_load_old_edges(emap, lvl->next, vvmap, dst, emid23, fmid, st2 * st3);
-    }
-  }
-}
-
-static void multires_mvert_to_ss(DerivedMesh *dm, MVert *mvert)
-{
-  CCGDerivedMesh *ccgdm = (CCGDerivedMesh *)dm;
-  CCGSubSurf *ss = ccgdm->ss;
-  CCGElem *vd;
-  CCGKey key;
-  int index;
-  int totvert, totedge, totface;
-  int gridSize = ccgSubSurf_getGridSize(ss);
-  int edgeSize = ccgSubSurf_getEdgeSize(ss);
-  int i = 0;
-
-  dm->getGridKey(dm, &key);
-
-  totface = ccgSubSurf_getNumFaces(ss);
-  for (index = 0; index < totface; index++) {
-    CCGFace *f = ccgdm->faceMap[index].face;
-    int x, y, S, numVerts = ccgSubSurf_getFaceNumVerts(f);
-
-    vd = ccgSubSurf_getFaceCenterData(f);
-    copy_v3_v3(CCG_elem_co(&key, vd), mvert[i].co);
-    i++;
-
-    for (S = 0; S < numVerts; S++) {
-      for (x = 1; x < gridSize - 1; x++, i++) {
-        vd = ccgSubSurf_getFaceGridEdgeData(ss, f, S, x);
-        copy_v3_v3(CCG_elem_co(&key, vd), mvert[i].co);
-      }
-    }
-
-    for (S = 0; S < numVerts; S++) {
-      for (y = 1; y < gridSize - 1; y++) {
-        for (x = 1; x < gridSize - 1; x++, i++) {
-          vd = ccgSubSurf_getFaceGridData(ss, f, S, x, y);
-          copy_v3_v3(CCG_elem_co(&key, vd), mvert[i].co);
-        }
-      }
-    }
-  }
-
-  totedge = ccgSubSurf_getNumEdges(ss);
-  for (index = 0; index < totedge; index++) {
-    CCGEdge *e = ccgdm->edgeMap[index].edge;
-    int x;
-
-    for (x = 1; x < edgeSize - 1; x++, i++) {
-      vd = ccgSubSurf_getEdgeData(ss, e, x);
-      copy_v3_v3(CCG_elem_co(&key, vd), mvert[i].co);
-    }
-  }
-
-  totvert = ccgSubSurf_getNumVerts(ss);
-  for (index = 0; index < totvert; index++) {
-    CCGVert *v = ccgdm->vertMap[index].vert;
-
-    vd = ccgSubSurf_getVertData(ss, v);
-    copy_v3_v3(CCG_elem_co(&key, vd), mvert[i].co);
-    i++;
-  }
-
-  ccgSubSurf_updateToFaces(ss, 0, NULL, 0);
-}
-
-/* Loads a multires object stored in the old Multires struct into the new format */
-static void multires_load_old_dm(DerivedMesh *dm, Mesh *me, int totlvl)
-{
-  MultiresLevel *lvl, *lvl1;
-  Multires *mr = me->mr;
-  MVert *vsrc, *vdst;
-  unsigned int src, dst;
-  int st_last = multires_side_tot[totlvl - 1] - 1;
-  int extedgelen = multires_side_tot[totlvl] - 2;
-  int *vvmap;  // inorder for dst, map to src
-  int crossedgelen;
-  int s, x, tottri, totquad;
-  unsigned int i, j, totvert;
-
-  src = 0;
-  vsrc = mr->verts;
-  vdst = dm->getVertArray(dm);
-  totvert = (unsigned int)dm->getNumVerts(dm);
-  vvmap = MEM_calloc_arrayN(totvert, sizeof(int), "multires vvmap");
-
-  if (!vvmap) {
-    return;
-  }
-
-  lvl1 = mr->levels.first;
-  /* Load base verts */
-  for (i = 0; i < lvl1->totvert; i++) {
-    vvmap[totvert - lvl1->totvert + i] = src;
-    src++;
-  }
-
-  /* Original edges */
-  dst = totvert - lvl1->totvert - extedgelen * lvl1->totedge;
-  for (i = 0; i < lvl1->totedge; i++) {
-    int ldst = dst + extedgelen * i;
-    int lsrc = src;
-    lvl = lvl1->next;
-
-    for (j = 2; j <= mr->level_count; j++) {
-      int base = multires_side_tot[totlvl - j + 1] - 2;
-      int skip = multires_side_tot[totlvl - j + 2] - 1;
-      int st = multires_side_tot[j - 1] - 1;
-
-      for (x = 0; x < st; x++) {
-        vvmap[ldst + base + x * skip] = lsrc + st * i + x;
-      }
-
-      lsrc += lvl->totvert - lvl->prev->totvert;
-      lvl = lvl->next;
-    }
-  }
-
-  /* Center points */
-  dst = 0;
-  for (i = 0; i < lvl1->totface; i++) {
-    int sides = lvl1->faces[i].v[3] ? 4 : 3;
-
-    vvmap[dst] = src + lvl1->totedge + i;
-    dst += 1 + sides * (st_last - 1) * st_last;
-  }
-
-  /* The rest is only for level 3 and up */
-  if (lvl1->next && lvl1->next->next) {
-    ListBase **fmap, **emap;
-    IndexNode **fmem, **emem;
-
-    /* Face edge cross */
-    tottri = totquad = 0;
-    crossedgelen = multires_side_tot[totlvl - 1] - 2;
-    dst = 0;
-    for (i = 0; i < lvl1->totface; i++) {
-      int sides = lvl1->faces[i].v[3] ? 4 : 3;
-
-      lvl = lvl1->next->next;
-      dst++;
-
-      for (j = 3; j <= mr->level_count; j++) {
-        int base = multires_side_tot[totlvl - j + 1] - 2;
-        int skip = multires_side_tot[totlvl - j + 2] - 1;
-        int st = pow(2, j - 2);
-        int st2 = pow(2, j - 3);
-        int lsrc = lvl->prev->totvert;
-
-        /* Skip exterior edge verts */
-        lsrc += lvl1->totedge * st;
-
-        /* Skip earlier face edge crosses */
-        lsrc += st2 * (tottri * 3 + totquad * 4);
-
-        for (s = 0; s < sides; s++) {
-          for (x = 0; x < st2; x++) {
-            vvmap[dst + crossedgelen * (s + 1) - base - x * skip - 1] = lsrc;
-            lsrc++;
-          }
-        }
-
-        lvl = lvl->next;
-      }
-
-      dst += sides * (st_last - 1) * st_last;
-
-      if (sides == 4) {
-        totquad++;
-      }
-      else {
-        tottri++;
-      }
-    }
-
-    /* calculate vert to edge/face maps for each level (except the last) */
-    fmap = MEM_calloc_arrayN((mr->level_count - 1), sizeof(ListBase *), "multires fmap");
-    emap = MEM_calloc_arrayN((mr->level_count - 1), sizeof(ListBase *), "multires emap");
-    fmem = MEM_calloc_arrayN((mr->level_count - 1), sizeof(IndexNode *), "multires fmem");
-    emem = MEM_calloc_arrayN((mr->level_count - 1), sizeof(IndexNode *), "multires emem");
-    lvl = lvl1;
-    for (i = 0; i < (unsigned int)mr->level_count - 1; i++) {
-      create_old_vert_face_map(fmap + i, fmem + i, lvl->faces, lvl->totvert, lvl->totface);
-      create_old_vert_edge_map(emap + i, emem + i, lvl->edges, lvl->totvert, lvl->totedge);
-      lvl = lvl->next;
-    }
-
-    /* Interior face verts */
-    /* lvl = lvl1->next->next; */ /* UNUSED */
-    dst = 0;
-    for (j = 0; j < lvl1->totface; j++) {
-      int sides = lvl1->faces[j].v[3] ? 4 : 3;
-      int ldst = dst + 1 + sides * (st_last - 1);
-
-      for (s = 0; s < sides; s++) {
-        int st2 = multires_side_tot[totlvl - 1] - 2;
-        int st3 = multires_side_tot[totlvl - 2] - 2;
-        int st4 = st3 == 0 ? 1 : (st3 + 1) / 2;
-        int mid = ldst + st2 * st3 + st3;
-        int cv = lvl1->faces[j].v[s];
-        int nv = lvl1->faces[j].v[s == sides - 1 ? 0 : s + 1];
-        int pv = lvl1->faces[j].v[s == 0 ? sides - 1 : s - 1];
-
-        multires_load_old_faces(fmap,
-                                emap,
-                                lvl1->next,
-                                vvmap,
-                                mid,
-                                vvmap[dst],
-                                cv,
-                                find_old_edge(emap[0], lvl1->edges, pv, cv)->mid,
-                                find_old_edge(emap[0], lvl1->edges, cv, nv)->mid,
-                                st2,
-                                st4);
-
-        ldst += (st_last - 1) * (st_last - 1);
-      }
-
-      dst = ldst;
-    }
-
-    /*lvl = lvl->next;*/ /*UNUSED*/
-
-    for (i = 0; i < (unsigned int)(mr->level_count - 1); i++) {
-      MEM_freeN(fmap[i]);
-      MEM_freeN(fmem[i]);
-      MEM_freeN(emap[i]);
-      MEM_freeN(emem[i]);
-    }
-
-    MEM_freeN(fmap);
-    MEM_freeN(emap);
-    MEM_freeN(fmem);
-    MEM_freeN(emem);
-  }
-
-  /* Transfer verts */
-  for (i = 0; i < totvert; i++) {
-    copy_v3_v3(vdst[i].co, vsrc[vvmap[i]].co);
-  }
-
-  MEM_freeN(vvmap);
-
-  multires_mvert_to_ss(dm, vdst);
-}
-
-/* Copy the first-level vcol data to the mesh, if it exists */
-/* Warning: higher-level vcol data will be lost */
-static void multires_load_old_vcols(Mesh *me)
-{
-  MultiresLevel *lvl;
-  MultiresColFace *colface;
-  MCol *mcol;
-  int i, j;
-
-  if (!(lvl = me->mr->levels.first)) {
-    return;
-  }
-
-  if (!(colface = lvl->colfaces)) {
-    return;
-  }
-
-  /* older multires format never supported multiple vcol layers,
-   * so we can assume the active vcol layer is the correct one */
-  if (!(mcol = CustomData_get_layer(&me->fdata, CD_MCOL))) {
-    return;
-  }
-
-  for (i = 0; i < me->totface; i++) {
-    for (j = 0; j < 4; j++) {
-      mcol[i * 4 + j].a = colface[i].col[j].a;
-      mcol[i * 4 + j].r = colface[i].col[j].r;
-      mcol[i * 4 + j].g = colface[i].col[j].g;
-      mcol[i * 4 + j].b = colface[i].col[j].b;
-    }
-  }
-}
-
-/* Copy the first-level face-flag data to the mesh */
-static void multires_load_old_face_flags(Mesh *me)
-{
-  MultiresLevel *lvl;
-  MultiresFace *faces;
-  int i;
-
-  if (!(lvl = me->mr->levels.first)) {
-    return;
-  }
-
-  if (!(faces = lvl->faces)) {
-    return;
-  }
-
-  for (i = 0; i < me->totface; i++) {
-    me->mface[i].flag = faces[i].flag;
-  }
-}
-
-void multires_load_old(Object *ob, Mesh *me)
-{
-  MultiresLevel *lvl;
-  ModifierData *md;
-  MultiresModifierData *mmd;
-  DerivedMesh *dm, *orig;
-  CustomDataLayer *l;
-  int i;
-
-  /* Load original level into the mesh */
-  lvl = me->mr->levels.first;
-  CustomData_free_layers(&me->vdata, CD_MVERT, lvl->totvert);
-  CustomData_free_layers(&me->edata, CD_MEDGE, lvl->totedge);
-  CustomData_free_layers(&me->fdata, CD_MFACE, lvl->totface);
-  me->totvert = lvl->totvert;
-  me->totedge = lvl->totedge;
-  me->totface = lvl->totface;
-  me->mvert = CustomData_add_layer(&me->vdata, CD_MVERT, CD_CALLOC, NULL, me->totvert);
-  me->medge = CustomData_add_layer(&me->edata, CD_MEDGE, CD_CALLOC, NULL, me->totedge);
-  me->mface = CustomData_add_layer(&me->fdata, CD_MFACE, CD_CALLOC, NULL, me->totface);
-  memcpy(me->mvert, me->mr->verts, sizeof(MVert) * me->totvert);
-  for (i = 0; i < me->totedge; i++) {
-    me->medge[i].v1 = lvl->edges[i].v[0];
-    me->medge[i].v2 = lvl->edges[i].v[1];
-  }
-  for (i = 0; i < me->totface; i++) {
-    me->mface[i].v1 = lvl->faces[i].v[0];
-    me->mface[i].v2 = lvl->faces[i].v[1];
-    me->mface[i].v3 = lvl->faces[i].v[2];
-    me->mface[i].v4 = lvl->faces[i].v[3];
-    me->mface[i].mat_nr = lvl->faces[i].mat_nr;
-  }
-
-  /* Copy the first-level data to the mesh */
-  /* XXX We must do this before converting tessfaces to polys/lopps! */
-  for (i = 0, l = me->mr->vdata.layers; i < me->mr->vdata.totlayer; i++, l++) {
-    CustomData_add_layer(&me->vdata, l->type, CD_REFERENCE, l->data, me->totvert);
-  }
-  for (i = 0, l = me->mr->fdata.layers; i < me->mr->fdata.totlayer; i++, l++) {
-    CustomData_add_layer(&me->fdata, l->type, CD_REFERENCE, l->data, me->totface);
-  }
-  CustomData_reset(&me->mr->vdata);
-  CustomData_reset(&me->mr->fdata);
-
-  multires_load_old_vcols(me);
-  multires_load_old_face_flags(me);
-
-  /* multiresModifier_subdivide_legacy (actually, multires_subdivide_legacy) expects polys, not
-   * tessfaces! */
-  BKE_mesh_convert_mfaces_to_mpolys(me);
-
-  /* Add a multires modifier to the object */
-  md = ob->modifiers.first;
-  while (md && BKE_modifier_get_info(md->type)->type == eModifierTypeType_OnlyDeform) {
-    md = md->next;
-  }
-  mmd = (MultiresModifierData *)BKE_modifier_new(eModifierType_Multires);
-  BLI_insertlinkbefore(&ob->modifiers, md, mmd);
-
-  for (i = 0; i < me->mr->level_count - 1; i++) {
-    multiresModifier_subdivide_legacy(mmd, NULL, ob, 1, 0);
-  }
-
-  mmd->lvl = mmd->totlvl;
-  orig = CDDM_from_mesh(me);
-  /* XXX We *must* alloc paint mask here, else we have some kind of mismatch in
-   *     multires_modifier_update_mdisps() (called by dm->release(dm)), which always creates the
-   *     reference subsurfed dm with this option, before calling multiresModifier_disp_run(),
-   *     which implicitly expects both subsurfs from its first dm and oldGridData parameters to
-   *     be of the same "format"! */
-  dm = multires_make_derived_from_derived(orig, mmd, NULL, ob, 0);
-
-  multires_load_old_dm(dm, me, mmd->totlvl + 1);
-
-  multires_dm_mark_as_modified(dm, MULTIRES_COORDS_MODIFIED);
-  dm->release(dm);
-  orig->release(orig);
-
-  /* Remove the old multires */
-  multires_free(me->mr);
-  me->mr = NULL;
-}
-
 /* If 'ob_src' and 'ob_dst' both have multires modifiers, synchronize them
  * such that 'ob_dst' has the same total number of levels as 'ob_src'. */
 void multiresModifier_sync_levels_ex(Object *ob_dst,
diff --git a/source/blender/blenloader/intern/versioning_250.c b/source/blender/blenloader/intern/versioning_250.c
index 5046ee6aab1..f7592308023 100644
--- a/source/blender/blenloader/intern/versioning_250.c
+++ b/source/blender/blenloader/intern/versioning_250.c
@@ -799,20 +799,6 @@ void blo_do_versions_250(FileData *fd, Library *lib, Main *bmain)
 
       // BLI_freelistN(&pidlist);
 
-      if (ob->type == OB_MESH) {
-        Mesh *me = blo_do_versions_newlibadr(fd, lib, ob->data);
-        void *olddata = ob->data;
-        ob->data = me;
-
-        /* XXX - library meshes crash on loading most yoFrankie levels,
-         * the multires pointer gets invalid -  Campbell */
-        if (me && me->id.lib == NULL && me->mr && me->mr->level_count > 1) {
-          multires_load_old(ob, me);
-        }
-
-        ob->data = olddata;
-      }
-
       if (ob->totcol && ob->matbits == NULL) {
         int a;
 
@@ -1152,7 +1138,7 @@ void blo_do_versions_250(FileData *fd, Library *lib, Main *bmain)
 
     if (bmain->versionfile == 250 && bmain->subversionfile > 1) {
       for (me = bmain->meshes.first; me; me = me->id.next) {
-        multires_load_old_250(me);
+        CustomData_free_layer_active(&me->fdata, CD_MDISPS, me->totface);
       }
 
       for (ob = bmain->objects.first; ob; ob = ob->id.next) {
diff --git a/source/blender/blenloader/intern/versioning_legacy.c b/source/blender/blenloader/intern/versioning_legacy.c
index 4acf98cc58b..9d858da266d 100644
--- a/source/blender/blenloader/intern/versioning_legacy.c
+++ b/source/blender/blenloader/intern/versioning_legacy.c
@@ -1959,7 +1959,6 @@ void blo_do_versions_pre250(FileData *fd, Library *lib, Main *bmain)
     Light *la;
     Material *ma;
     ParticleSettings *part;
-    Mesh *me;
     bNodeTree *ntree;
     Tex *tex;
     ModifierData *md;
@@ -2074,23 +2073,6 @@ void blo_do_versions_pre250(FileData *fd, Library *lib, Main *bmain)
       }
     }
 
-    /* Copy over old per-level multires vertex data
-     * into a single vertex array in struct Multires */
-    for (me = bmain->meshes.first; me; me = me->id.next) {
-      if (me->mr && !me->mr->verts) {
-        MultiresLevel *lvl = me->mr->levels.last;
-        if (lvl) {
-          me->mr->verts = lvl->verts;
-          lvl->verts = NULL;
-          /* Don't need the other vert arrays */
-          for (lvl = lvl->prev; lvl; lvl = lvl->prev) {
-            MEM_freeN(lvl->verts);
-            lvl->verts = NULL;
-          }
-        }
-      }
-    }
-
     if (bmain->versionfile != 245 || bmain->subversionfile < 1) {
       for (la = bmain->lights.first; la; la = la->id.next) {
         la->falloff_type = LA_FALLOFF_INVLINEAR;
diff --git a/source/blender/makesdna/DNA_mesh_types.h b/source/blender/makesdna/DNA_mesh_types.h
index e2837ba85f8..a822a6723fa 100644
--- a/source/blender/makesdna/DNA_mesh_types.h
+++ b/source/blender/makesdna/DNA_mesh_types.h
@@ -48,7 +48,6 @@ struct MPropCol;
 struct MVert;
 struct Material;
 struct Mesh;
-struct Multires;
 struct SubdivCCG;
 
 #
@@ -230,9 +229,6 @@ typedef struct Mesh {
    * default and Face Sets can be used without affecting the color of the mesh. */
   int face_sets_color_default;
 
-  /** Deprecated multiresolution modeling data, only keep for loading old files. */
-  struct Multires *mr DNA_DEPRECATED;
-
   Mesh_Runtime runtime;
 } Mesh;
 
diff --git a/source/blender/makesdna/DNA_meshdata_types.h b/source/blender/makesdna/DNA_meshdata_types.h
index 45bf6e8c282..7cc94a2ad0b 100644
--- a/source/blender/makesdna/DNA_meshdata_types.h
+++ b/source/blender/makesdna/DNA_meshdata_types.h
@@ -518,54 +518,4 @@ typedef struct MRecast {
   int i;
 } MRecast;
 
-/** Multires structs kept for compatibility with old files. */
-typedef struct MultiresCol {
-  float a, r, g, b;
-} MultiresCol;
-
-typedef struct MultiresColFace {
-  /* vertex colors */
-  MultiresCol col[4];
-} MultiresColFace;
-
-typedef struct MultiresFace {
-  unsigned int v[4];
-  unsigned int mid;
-  char flag, mat_nr, _pad[2];
-} MultiresFace;
-
-typedef struct MultiresEdge {
-  unsigned int v[2];
-  unsigned int mid;
-} MultiresEdge;
-
-typedef struct MultiresLevel {
-  struct MultiresLevel *next, *prev;
-
-  MultiresFace *faces;
-  MultiresColFace *colfaces;
-  MultiresEdge *edges;
-
-  unsigned int totvert, totface, totedge;
-  char _pad[4];
-
-  /* Kept for compatibility with even older files */
-  MVert *verts;
-} MultiresLevel;
-
-typedef struct Multires {
-  ListBase levels;
-  MVert *verts;
-
-  unsigned char level_count, current, newlvl, edgelvl, pinlvl, renderlvl;
-  unsigned char use_col, flag;
-
-  /* Special level 1 data that cannot be modified from other levels */
-  CustomData vdata;
-  CustomData fdata;
-  short *edge_flags;
-  char *edge_creases;
-} Multires;
-/* End multi-res structs. */
-
 /** \} */