Quadriflow: Symmetry support

This patch adds paint symmetry support to Quadriflow. It bisects and mirrors the input and the output from the remesher to build the final mesh using the preserve boundary option.
This is also an important performance improvement in Quadriflow because it only needs to process half of the mesh with half the resolution.

Reviewed By: jbakker

Differential Revision: https://developer.blender.org/D5855

5 files changed, 582 insertions, 377 deletions

diff --git a/source/blender/blenkernel/BKE_mirror.h b/source/blender/blenkernel/BKE_mirror.h
new file mode 100644
index 00000000000..20eb8a920fc
--- /dev/null
+++ b/source/blender/blenkernel/BKE_mirror.h
@@ -0,0 +1,45 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2019 Blender Foundation.
+ * All rights reserved.
+ */
+
+#ifndef __BKE_MIRROR_H__
+#define __BKE_MIRROR_H__
+
+/** \file
+ * \ingroup bke
+ */
+
+#include "BLI_utildefines.h"
+
+struct MirrorModifierData;
+struct ModifierEvalContext;
+struct Object;
+
+struct Mesh *BKE_mirror_bisect_on_mirror_plane(struct MirrorModifierData *mmd,
+                                               const struct Mesh *mesh,
+                                               int axis,
+                                               const float plane_co[3],
+                                               float plane_no[3]);
+
+struct Mesh *BKE_mirror_apply_mirror_on_axis(struct MirrorModifierData *mmd,
+                                             const struct ModifierEvalContext *UNUSED(ctx),
+                                             struct Object *ob,
+                                             const struct Mesh *mesh,
+                                             int axis);
+
+#endif /* __BKE_MIRROR_H__ */
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 834f4dd1b9e..f598a81ff5e 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -159,6 +159,7 @@ set(SRC
   intern/mesh_runtime.c
   intern/mesh_tangent.c
   intern/mesh_validate.c
+  intern/mirror.c
   intern/modifier.c
   intern/movieclip.c
   intern/multires.c
@@ -312,6 +313,7 @@ set(SRC
   BKE_mesh_remesh_voxel.h
   BKE_mesh_runtime.h
   BKE_mesh_tangent.h
+  BKE_mirror.h
   BKE_modifier.h
   BKE_movieclip.h
   BKE_multires.h
diff --git a/source/blender/blenkernel/intern/mirror.c b/source/blender/blenkernel/intern/mirror.c
new file mode 100644
index 00000000000..f7677d7441a
--- /dev/null
+++ b/source/blender/blenkernel/intern/mirror.c
@@ -0,0 +1,413 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup bke
+ */
+
+#include "BLI_math.h"
+
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_object_types.h"
+
+#include "BKE_library.h"
+#include "BKE_library_query.h"
+#include "BKE_mesh.h"
+#include "BKE_modifier.h"
+#include "BKE_deform.h"
+
+#include "bmesh.h"
+#include "bmesh_tools.h"
+
+#include "MEM_guardedalloc.h"
+
+#include "MOD_modifiertypes.h"
+
+
+Mesh *BKE_mirror_bisect_on_mirror_plane(MirrorModifierData *mmd,
+                                        const Mesh *mesh,
+                                        int axis,
+                                        const float plane_co[3],
+                                        float plane_no[3])
+{
+  bool do_bisect_flip_axis = ((axis == 0 && mmd->flag & MOD_MIR_BISECT_FLIP_AXIS_X) ||
+                              (axis == 1 && mmd->flag & MOD_MIR_BISECT_FLIP_AXIS_Y) ||
+                              (axis == 2 && mmd->flag & MOD_MIR_BISECT_FLIP_AXIS_Z));
+
+  const float bisect_distance = 0.001f;
+
+  Mesh *result;
+  BMesh *bm;
+  BMIter viter;
+  BMVert *v, *v_next;
+
+  bm = BKE_mesh_to_bmesh_ex(mesh,
+                            &(struct BMeshCreateParams){0},
+                            &(struct BMeshFromMeshParams){
+                                .calc_face_normal = true,
+                                .cd_mask_extra = {.vmask = CD_MASK_ORIGINDEX,
+                                                  .emask = CD_MASK_ORIGINDEX,
+                                                  .pmask = CD_MASK_ORIGINDEX},
+                            });
+
+  /* Define bisecting plane (aka mirror plane). */
+  float plane[4];
+  if (!do_bisect_flip_axis) {
+    /* That reversed condition is a tad weird, but for some reason that's how you keep
+     * the part of the mesh which is on the non-mirrored side when flip option is disabled,
+     * think that that is the expected behavior. */
+    negate_v3(plane_no);
+  }
+  plane_from_point_normal_v3(plane, plane_co, plane_no);
+
+  BM_mesh_bisect_plane(bm, plane, false, false, 0, 0, bisect_distance);
+
+  /* Plane definitions for vert killing. */
+  float plane_offset[4];
+  copy_v3_v3(plane_offset, plane);
+  plane_offset[3] = plane[3] - bisect_distance;
+
+  /* Delete verts across the mirror plane. */
+  BM_ITER_MESH_MUTABLE (v, v_next, &viter, bm, BM_VERTS_OF_MESH) {
+    if (plane_point_side_v3(plane_offset, v->co) > 0.0f) {
+      BM_vert_kill(bm, v);
+    }
+  }
+
+  result = BKE_mesh_from_bmesh_for_eval_nomain(bm, NULL, mesh);
+  BM_mesh_free(bm);
+
+  return result;
+}
+
+Mesh *BKE_mirror_apply_mirror_on_axis(MirrorModifierData *mmd,
+                                      const ModifierEvalContext *UNUSED(ctx),
+                                      Object *ob,
+                                      const Mesh *mesh,
+                                      int axis)
+{
+  const float tolerance_sq = mmd->tolerance * mmd->tolerance;
+  const bool do_vtargetmap = (mmd->flag & MOD_MIR_NO_MERGE) == 0;
+  int tot_vtargetmap = 0; /* total merge vertices */
+
+  const bool do_bisect = ((axis == 0 && mmd->flag & MOD_MIR_BISECT_AXIS_X) ||
+                          (axis == 1 && mmd->flag & MOD_MIR_BISECT_AXIS_Y) ||
+                          (axis == 2 && mmd->flag & MOD_MIR_BISECT_AXIS_Z));
+
+  Mesh *result;
+  MVert *mv, *mv_prev;
+  MEdge *me;
+  MLoop *ml;
+  MPoly *mp;
+  float mtx[4][4];
+  float plane_co[3], plane_no[3];
+  int i;
+  int a, totshape;
+  int *vtargetmap = NULL, *vtmap_a = NULL, *vtmap_b = NULL;
+
+  /* mtx is the mirror transformation */
+  unit_m4(mtx);
+  mtx[axis][axis] = -1.0f;
+
+  Object *mirror_ob = mmd->mirror_ob;
+  if (mirror_ob != NULL) {
+    float tmp[4][4];
+    float itmp[4][4];
+
+    /* tmp is a transform from coords relative to the object's own origin,
+     * to coords relative to the mirror object origin */
+    invert_m4_m4(tmp, mirror_ob->obmat);
+    mul_m4_m4m4(tmp, tmp, ob->obmat);
+
+    /* itmp is the reverse transform back to origin-relative coordinates */
+    invert_m4_m4(itmp, tmp);
+
+    /* combine matrices to get a single matrix that translates coordinates into
+     * mirror-object-relative space, does the mirror, and translates back to
+     * origin-relative space */
+    mul_m4_series(mtx, itmp, mtx, tmp);
+
+    if (do_bisect) {
+      copy_v3_v3(plane_co, itmp[3]);
+      copy_v3_v3(plane_no, itmp[axis]);
+    }
+  }
+  else if (do_bisect) {
+    copy_v3_v3(plane_co, mtx[3]);
+    /* Need to negate here, since that axis is inverted (for mirror transform). */
+    negate_v3_v3(plane_no, mtx[axis]);
+  }
+
+  Mesh *mesh_bisect = NULL;
+  if (do_bisect) {
+    mesh_bisect = BKE_mirror_bisect_on_mirror_plane(mmd, mesh, axis, plane_co, plane_no);
+    mesh = mesh_bisect;
+  }
+
+  const int maxVerts = mesh->totvert;
+  const int maxEdges = mesh->totedge;
+  const int maxLoops = mesh->totloop;
+  const int maxPolys = mesh->totpoly;
+
+  result = BKE_mesh_new_nomain_from_template(
+      mesh, maxVerts * 2, maxEdges * 2, 0, maxLoops * 2, maxPolys * 2);
+
+  /*copy customdata to original geometry*/
+  CustomData_copy_data(&mesh->vdata, &result->vdata, 0, 0, maxVerts);
+  CustomData_copy_data(&mesh->edata, &result->edata, 0, 0, maxEdges);
+  CustomData_copy_data(&mesh->ldata, &result->ldata, 0, 0, maxLoops);
+  CustomData_copy_data(&mesh->pdata, &result->pdata, 0, 0, maxPolys);
+
+  /* Subsurf for eg won't have mesh data in the custom data arrays.
+   * now add mvert/medge/mpoly layers. */
+  if (!CustomData_has_layer(&mesh->vdata, CD_MVERT)) {
+    memcpy(result->mvert, mesh->mvert, sizeof(*result->mvert) * mesh->totvert);
+  }
+  if (!CustomData_has_layer(&mesh->edata, CD_MEDGE)) {
+    memcpy(result->medge, mesh->medge, sizeof(*result->medge) * mesh->totedge);
+  }
+  if (!CustomData_has_layer(&mesh->pdata, CD_MPOLY)) {
+    memcpy(result->mloop, mesh->mloop, sizeof(*result->mloop) * mesh->totloop);
+    memcpy(result->mpoly, mesh->mpoly, sizeof(*result->mpoly) * mesh->totpoly);
+  }
+
+  /* copy customdata to new geometry,
+   * copy from its self because this data may have been created in the checks above */
+  CustomData_copy_data(&result->vdata, &result->vdata, 0, maxVerts, maxVerts);
+  CustomData_copy_data(&result->edata, &result->edata, 0, maxEdges, maxEdges);
+  /* loops are copied later */
+  CustomData_copy_data(&result->pdata, &result->pdata, 0, maxPolys, maxPolys);
+
+  if (do_vtargetmap) {
+    /* second half is filled with -1 */
+    vtargetmap = MEM_malloc_arrayN(maxVerts, 2 * sizeof(int), "MOD_mirror tarmap");
+
+    vtmap_a = vtargetmap;
+    vtmap_b = vtargetmap + maxVerts;
+  }
+
+  /* mirror vertex coordinates */
+  mv_prev = result->mvert;
+  mv = mv_prev + maxVerts;
+  for (i = 0; i < maxVerts; i++, mv++, mv_prev++) {
+    mul_m4_v3(mtx, mv->co);
+
+    if (do_vtargetmap) {
+      /* compare location of the original and mirrored vertex, to see if they
+       * should be mapped for merging */
+      if (UNLIKELY(len_squared_v3v3(mv_prev->co, mv->co) < tolerance_sq)) {
+        *vtmap_a = maxVerts + i;
+        tot_vtargetmap++;
+
+        /* average location */
+        mid_v3_v3v3(mv->co, mv_prev->co, mv->co);
+        copy_v3_v3(mv_prev->co, mv->co);
+      }
+      else {
+        *vtmap_a = -1;
+      }
+
+      *vtmap_b = -1; /* fill here to avoid 2x loops */
+
+      vtmap_a++;
+      vtmap_b++;
+    }
+  }
+
+  /* handle shape keys */
+  totshape = CustomData_number_of_layers(&result->vdata, CD_SHAPEKEY);
+  for (a = 0; a < totshape; a++) {
+    float(*cos)[3] = CustomData_get_layer_n(&result->vdata, CD_SHAPEKEY, a);
+    for (i = maxVerts; i < result->totvert; i++) {
+      mul_m4_v3(mtx, cos[i]);
+    }
+  }
+
+  /* adjust mirrored edge vertex indices */
+  me = result->medge + maxEdges;
+  for (i = 0; i < maxEdges; i++, me++) {
+    me->v1 += maxVerts;
+    me->v2 += maxVerts;
+  }
+
+  /* adjust mirrored poly loopstart indices, and reverse loop order (normals) */
+  mp = result->mpoly + maxPolys;
+  ml = result->mloop;
+  for (i = 0; i < maxPolys; i++, mp++) {
+    MLoop *ml2;
+    int j, e;
+
+    /* reverse the loop, but we keep the first vertex in the face the same,
+     * to ensure that quads are split the same way as on the other side */
+    CustomData_copy_data(
+        &result->ldata, &result->ldata, mp->loopstart, mp->loopstart + maxLoops, 1);
+
+    for (j = 1; j < mp->totloop; j++) {
+      CustomData_copy_data(&result->ldata,
+                           &result->ldata,
+                           mp->loopstart + j,
+                           mp->loopstart + maxLoops + mp->totloop - j,
+                           1);
+    }
+
+    ml2 = ml + mp->loopstart + maxLoops;
+    e = ml2[0].e;
+    for (j = 0; j < mp->totloop - 1; j++) {
+      ml2[j].e = ml2[j + 1].e;
+    }
+    ml2[mp->totloop - 1].e = e;
+
+    mp->loopstart += maxLoops;
+  }
+
+  /* adjust mirrored loop vertex and edge indices */
+  ml = result->mloop + maxLoops;
+  for (i = 0; i < maxLoops; i++, ml++) {
+    ml->v += maxVerts;
+    ml->e += maxEdges;
+  }
+
+  /* handle uvs,
+   * let tessface recalc handle updating the MTFace data */
+  if (mmd->flag & (MOD_MIR_MIRROR_U | MOD_MIR_MIRROR_V) ||
+      (is_zero_v2(mmd->uv_offset_copy) == false)) {
+    const bool do_mirr_u = (mmd->flag & MOD_MIR_MIRROR_U) != 0;
+    const bool do_mirr_v = (mmd->flag & MOD_MIR_MIRROR_V) != 0;
+
+    const int totuv = CustomData_number_of_layers(&result->ldata, CD_MLOOPUV);
+
+    for (a = 0; a < totuv; a++) {
+      MLoopUV *dmloopuv = CustomData_get_layer_n(&result->ldata, CD_MLOOPUV, a);
+      int j = maxLoops;
+      dmloopuv += j; /* second set of loops only */
+      for (; j-- > 0; dmloopuv++) {
+        if (do_mirr_u) {
+          dmloopuv->uv[0] = 1.0f - dmloopuv->uv[0] + mmd->uv_offset[0];
+        }
+        if (do_mirr_v) {
+          dmloopuv->uv[1] = 1.0f - dmloopuv->uv[1] + mmd->uv_offset[1];
+        }
+        dmloopuv->uv[0] += mmd->uv_offset_copy[0];
+        dmloopuv->uv[1] += mmd->uv_offset_copy[1];
+      }
+    }
+  }
+
+  /* handle custom split normals */
+  if (ob->type == OB_MESH && (((Mesh *)ob->data)->flag & ME_AUTOSMOOTH) &&
+      CustomData_has_layer(&result->ldata, CD_CUSTOMLOOPNORMAL)) {
+    const int totloop = result->totloop;
+    const int totpoly = result->totpoly;
+    float(*loop_normals)[3] = MEM_calloc_arrayN((size_t)totloop, sizeof(*loop_normals), __func__);
+    CustomData *ldata = &result->ldata;
+    short(*clnors)[2] = CustomData_get_layer(ldata, CD_CUSTOMLOOPNORMAL);
+    MLoopNorSpaceArray lnors_spacearr = {NULL};
+    float(*poly_normals)[3] = MEM_mallocN(sizeof(*poly_normals) * totpoly, __func__);
+
+    /* calculate custom normals into loop_normals, then mirror first half into second half */
+
+    BKE_mesh_calc_normals_poly(result->mvert,
+                               NULL,
+                               result->totvert,
+                               result->mloop,
+                               result->mpoly,
+                               totloop,
+                               totpoly,
+                               poly_normals,
+                               false);
+
+    BKE_mesh_normals_loop_split(result->mvert,
+                                result->totvert,
+                                result->medge,
+                                result->totedge,
+                                result->mloop,
+                                loop_normals,
+                                totloop,
+                                result->mpoly,
+                                poly_normals,
+                                totpoly,
+                                true,
+                                mesh->smoothresh,
+                                &lnors_spacearr,
+                                clnors,
+                                NULL);
+
+    /* mirroring has to account for loops being reversed in polys in second half */
+    mp = result->mpoly;
+    for (i = 0; i < maxPolys; i++, mp++) {
+      MPoly *mpmirror = result->mpoly + maxPolys + i;
+      int j;
+
+      for (j = mp->loopstart; j < mp->loopstart + mp->totloop; j++) {
+        int mirrorj = mpmirror->loopstart;
+        if (j > mp->loopstart) {
+          mirrorj += mpmirror->totloop - (j - mp->loopstart);
+        }
+        copy_v3_v3(loop_normals[mirrorj], loop_normals[j]);
+        loop_normals[mirrorj][axis] = -loop_normals[j][axis];
+        BKE_lnor_space_custom_normal_to_data(
+            lnors_spacearr.lspacearr[mirrorj], loop_normals[mirrorj], clnors[mirrorj]);
+      }
+    }
+
+    MEM_freeN(poly_normals);
+    MEM_freeN(loop_normals);
+    BKE_lnor_spacearr_free(&lnors_spacearr);
+  }
+
+  /* handle vgroup stuff */
+  if ((mmd->flag & MOD_MIR_VGROUP) && CustomData_has_layer(&result->vdata, CD_MDEFORMVERT)) {
+    MDeformVert *dvert = (MDeformVert *)CustomData_get_layer(&result->vdata, CD_MDEFORMVERT) +
+                         maxVerts;
+    int *flip_map = NULL, flip_map_len = 0;
+
+    flip_map = defgroup_flip_map(ob, &flip_map_len, false);
+
+    if (flip_map) {
+      for (i = 0; i < maxVerts; dvert++, i++) {
+        /* merged vertices get both groups, others get flipped */
+        if (do_vtargetmap && (vtargetmap[i] != -1)) {
+          defvert_flip_merged(dvert, flip_map, flip_map_len);
+        }
+        else {
+          defvert_flip(dvert, flip_map, flip_map_len);
+        }
+      }
+
+      MEM_freeN(flip_map);
+    }
+  }
+
+  if (do_vtargetmap) {
+    /* slow - so only call if one or more merge verts are found,
+     * users may leave this on and not realize there is nothing to merge - campbell */
+    if (tot_vtargetmap) {
+      result = BKE_mesh_merge_verts(
+          result, vtargetmap, tot_vtargetmap, MESH_MERGE_VERTS_DUMP_IF_MAPPED);
+    }
+    MEM_freeN(vtargetmap);
+  }
+
+  if (mesh_bisect != NULL) {
+    BKE_id_free(NULL, mesh_bisect);
+  }
+
+  return result;
+}
diff --git a/source/blender/editors/object/object_remesh.c b/source/blender/editors/object/object_remesh.c
index 6075867b552..f8ca3b268cc 100644
--- a/source/blender/editors/object/object_remesh.c
+++ b/source/blender/editors/object/object_remesh.c
@@ -40,10 +40,12 @@
 
 #include "BKE_context.h"
 #include "BKE_global.h"
+#include "BKE_library.h"
 #include "BKE_main.h"
 #include "BKE_mesh.h"
 #include "BKE_mesh_runtime.h"
-#include "BKE_library.h"
+#include "BKE_mirror.h"
+#include "BKE_modifier.h"
 #include "BKE_object.h"
 #include "BKE_paint.h"
 #include "BKE_report.h"
@@ -170,14 +172,26 @@ enum {
 
 /****************** quadriflow remesh operator *********************/
 
+#define QUADRIFLOW_MIRROR_BISECT_TOLERANCE 0.005f
+
+typedef enum eSymmetryAxes {
+  SYMMETRY_AXES_X = (1 << 0),
+  SYMMETRY_AXES_Y = (1 << 1),
+  SYMMETRY_AXES_Z = (1 << 2),
+} eSymmetryAxes;
+
 typedef struct QuadriFlowJob {
   /* from wmJob */
   struct Object *owner;
+  struct Main *bmain;
   short *stop, *do_update;
   float *progress;
 
   int target_faces;
   int seed;
+  bool use_paint_symmetry;
+  eSymmetryAxes symmetry_axes;
+
   bool use_preserve_sharp;
   bool use_preserve_boundary;
   bool use_mesh_curvature;
@@ -228,6 +242,66 @@ static void quadriflow_update_job(void *customdata, float progress, int *cancel)
   *(qj->progress) = progress;
 }
 
+static Mesh *remesh_symmetry_bisect(Main *bmain, Mesh *mesh, eSymmetryAxes symmetry_axes)
+{
+  MirrorModifierData mmd = {0};
+  mmd.tolerance = QUADRIFLOW_MIRROR_BISECT_TOLERANCE;
+
+  Mesh *mesh_bisect, *mesh_bisect_temp;
+  mesh_bisect = BKE_mesh_copy(bmain, mesh);
+
+  int axis;
+  float plane_co[3], plane_no[3];
+  zero_v3(plane_co);
+
+  for (char i = 0; i < 3; i++) {
+    eSymmetryAxes symm_it = (eSymmetryAxes)(1 << i);
+    if (symmetry_axes & symm_it) {
+      axis = i;
+      mmd.flag = 0;
+      mmd.flag &= MOD_MIR_BISECT_AXIS_X << i;
+      zero_v3(plane_no);
+      plane_no[axis] = -1.0f;
+      mesh_bisect_temp = mesh_bisect;
+      mesh_bisect = BKE_mirror_bisect_on_mirror_plane(&mmd, mesh_bisect, axis, plane_co, plane_no);
+      if (mesh_bisect_temp != mesh_bisect) {
+        BKE_id_free(bmain, mesh_bisect_temp);
+      }
+    }
+  }
+
+  BKE_id_free(bmain, mesh);
+
+  return mesh_bisect;
+}
+
+static Mesh *remesh_symmetry_mirror(Object *ob, Mesh *mesh, eSymmetryAxes symmetry_axes)
+{
+  MirrorModifierData mmd = {0};
+  mmd.tolerance = QUADRIFLOW_MIRROR_BISECT_TOLERANCE;
+  Mesh *mesh_mirror, *mesh_mirror_temp;
+
+  mesh_mirror = mesh;
+
+  int axis;
+
+  for (char i = 0; i < 3; i++) {
+    eSymmetryAxes symm_it = (eSymmetryAxes)(1 << i);
+    if (symmetry_axes & symm_it) {
+      axis = i;
+      mmd.flag = 0;
+      mmd.flag &= MOD_MIR_AXIS_X << i;
+      mesh_mirror_temp = mesh_mirror;
+      mesh_mirror = BKE_mirror_apply_mirror_on_axis(&mmd, NULL, ob, mesh_mirror, axis);
+      if (mesh_mirror_temp != mesh_mirror) {
+        BKE_id_free(NULL, mesh_mirror_temp);
+      }
+    }
+  }
+
+  return mesh_mirror;
+}
+
 static void quadriflow_start_job(void *customdata, short *stop, short *do_update, float *progress)
 {
   QuadriFlowJob *qj = customdata;
@@ -242,16 +316,27 @@ static void quadriflow_start_job(void *customdata, short *stop, short *do_update
   Object *ob = qj->owner;
   Mesh *mesh = ob->data;
   Mesh *new_mesh;
+  Mesh *bisect_mesh;
+
+  /* Run Quadriflow bisect operations on a copy of the mesh to keep the code readable without
+   * freeing the original ID */
+  bisect_mesh = BKE_mesh_copy(qj->bmain, mesh);
+
+  /* Bisect the input mesh using the paint symmetry settings */
+  bisect_mesh = remesh_symmetry_bisect(qj->bmain, bisect_mesh, qj->symmetry_axes);
 
-  new_mesh = BKE_mesh_remesh_quadriflow_to_mesh_nomain(mesh,
+  new_mesh = BKE_mesh_remesh_quadriflow_to_mesh_nomain(bisect_mesh,
                                                        qj->target_faces,
                                                        qj->seed,
                                                        qj->use_preserve_sharp,
-                                                       qj->use_preserve_boundary,
+                                                       qj->use_preserve_boundary ||
+                                                           qj->use_paint_symmetry,
                                                        qj->use_mesh_curvature,
                                                        quadriflow_update_job,
                                                        (void *)qj);
 
+  BKE_id_free(qj->bmain, bisect_mesh);
+
   if (!new_mesh) {
     *do_update = true;
     *stop = 0;
@@ -262,6 +347,11 @@ static void quadriflow_start_job(void *customdata, short *stop, short *do_update
     return;
   }
 
+  /* Mirror the Quadriflow result to build the final mesh */
+  if (new_mesh) {
+    new_mesh = remesh_symmetry_mirror(qj->owner, new_mesh, qj->symmetry_axes);
+  }
+
   if (ob->mode == OB_MODE_SCULPT) {
     ED_sculpt_undo_geometry_begin(ob);
   }
@@ -314,10 +404,13 @@ static int quadriflow_remesh_exec(bContext *C, wmOperator *op)
   QuadriFlowJob *job = MEM_mallocN(sizeof(QuadriFlowJob), "QuadriFlowJob");
 
   job->owner = CTX_data_active_object(C);
+  job->bmain = CTX_data_main(C);
 
   job->target_faces = RNA_int_get(op->ptr, "target_faces");
   job->seed = RNA_int_get(op->ptr, "seed");
 
+  job->use_paint_symmetry = RNA_boolean_get(op->ptr, "use_paint_symmetry");
+
   job->use_preserve_sharp = RNA_boolean_get(op->ptr, "use_preserve_sharp");
   job->use_preserve_boundary = RNA_boolean_get(op->ptr, "use_preserve_boundary");
 
@@ -326,6 +419,22 @@ static int quadriflow_remesh_exec(bContext *C, wmOperator *op)
   job->preserve_paint_mask = RNA_boolean_get(op->ptr, "preserve_paint_mask");
   job->smooth_normals = RNA_boolean_get(op->ptr, "smooth_normals");
 
+  /* Update the target face count if symmetry is enabled */
+  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
+  if (sd && job->use_paint_symmetry) {
+    job->symmetry_axes = (eSymmetryAxes)(sd->paint.symmetry_flags & PAINT_SYMM_AXIS_ALL);
+    for (char i = 0; i < 3; i++) {
+      eSymmetryAxes symm_it = (eSymmetryAxes)(1 << i);
+      if (job->symmetry_axes & symm_it) {
+        job->target_faces = job->target_faces / 2;
+      }
+    }
+  }
+  else {
+    job->use_paint_symmetry = false;
+    job->symmetry_axes = 0;
+  }
+
   wmJob *wm_job = WM_jobs_get(CTX_wm_manager(C),
                               CTX_wm_window(C),
                               CTX_data_scene(C),
@@ -450,6 +559,12 @@ void OBJECT_OT_quadriflow_remesh(wmOperatorType *ot)
 
   /* properties */
   RNA_def_boolean(ot->srna,
+                  "use_paint_symmetry",
+                  true,
+                  "Use Paint Symmetry",
+                  "Generates a symmetrycal mesh using the paint symmetry configuration");
+
+  RNA_def_boolean(ot->srna,
                   "use_preserve_sharp",
                   false,
                   "Preserve Sharp",
diff --git a/source/blender/modifiers/intern/MOD_mirror.c b/source/blender/modifiers/intern/MOD_mirror.c
index c91f5d41c5e..47f8528ee94 100644
--- a/source/blender/modifiers/intern/MOD_mirror.c
+++ b/source/blender/modifiers/intern/MOD_mirror.c
@@ -30,6 +30,7 @@
 #include "BKE_library.h"
 #include "BKE_library_query.h"
 #include "BKE_mesh.h"
+#include "BKE_mirror.h"
 #include "BKE_modifier.h"
 #include "BKE_deform.h"
 
@@ -68,377 +69,6 @@ static void updateDepsgraph(ModifierData *md, const ModifierUpdateDepsgraphConte
   }
 }
 
-static Mesh *doBiscetOnMirrorPlane(MirrorModifierData *mmd,
-                                   const Mesh *mesh,
-                                   int axis,
-                                   const float plane_co[3],
-                                   float plane_no[3])
-{
-  bool do_bisect_flip_axis = ((axis == 0 && mmd->flag & MOD_MIR_BISECT_FLIP_AXIS_X) ||
-                              (axis == 1 && mmd->flag & MOD_MIR_BISECT_FLIP_AXIS_Y) ||
-                              (axis == 2 && mmd->flag & MOD_MIR_BISECT_FLIP_AXIS_Z));
-
-  const float bisect_distance = 0.001f;
-
-  Mesh *result;
-  BMesh *bm;
-  BMIter viter;
-  BMVert *v, *v_next;
-
-  bm = BKE_mesh_to_bmesh_ex(mesh,
-                            &(struct BMeshCreateParams){0},
-                            &(struct BMeshFromMeshParams){
-                                .calc_face_normal = true,
-                                .cd_mask_extra = {.vmask = CD_MASK_ORIGINDEX,
-                                                  .emask = CD_MASK_ORIGINDEX,
-                                                  .pmask = CD_MASK_ORIGINDEX},
-                            });
-
-  /* Define bisecting plane (aka mirror plane). */
-  float plane[4];
-  if (!do_bisect_flip_axis) {
-    /* That reversed condition is a tad weird, but for some reason that's how you keep
-     * the part of the mesh which is on the non-mirrored side when flip option is disabled,
-     * think that that is the expected behavior. */
-    negate_v3(plane_no);
-  }
-  plane_from_point_normal_v3(plane, plane_co, plane_no);
-
-  BM_mesh_bisect_plane(bm, plane, false, false, 0, 0, bisect_distance);
-
-  /* Plane definitions for vert killing. */
-  float plane_offset[4];
-  copy_v3_v3(plane_offset, plane);
-  plane_offset[3] = plane[3] - bisect_distance;
-
-  /* Delete verts across the mirror plane. */
-  BM_ITER_MESH_MUTABLE (v, v_next, &viter, bm, BM_VERTS_OF_MESH) {
-    if (plane_point_side_v3(plane_offset, v->co) > 0.0f) {
-      BM_vert_kill(bm, v);
-    }
-  }
-
-  result = BKE_mesh_from_bmesh_for_eval_nomain(bm, NULL, mesh);
-  BM_mesh_free(bm);
-
-  return result;
-}
-
-static Mesh *doMirrorOnAxis(MirrorModifierData *mmd,
-                            const ModifierEvalContext *UNUSED(ctx),
-                            Object *ob,
-                            const Mesh *mesh,
-                            int axis)
-{
-  const float tolerance_sq = mmd->tolerance * mmd->tolerance;
-  const bool do_vtargetmap = (mmd->flag & MOD_MIR_NO_MERGE) == 0;
-  int tot_vtargetmap = 0; /* total merge vertices */
-
-  const bool do_bisect = ((axis == 0 && mmd->flag & MOD_MIR_BISECT_AXIS_X) ||
-                          (axis == 1 && mmd->flag & MOD_MIR_BISECT_AXIS_Y) ||
-                          (axis == 2 && mmd->flag & MOD_MIR_BISECT_AXIS_Z));
-
-  Mesh *result;
-  MVert *mv, *mv_prev;
-  MEdge *me;
-  MLoop *ml;
-  MPoly *mp;
-  float mtx[4][4];
-  float plane_co[3], plane_no[3];
-  int i;
-  int a, totshape;
-  int *vtargetmap = NULL, *vtmap_a = NULL, *vtmap_b = NULL;
-
-  /* mtx is the mirror transformation */
-  unit_m4(mtx);
-  mtx[axis][axis] = -1.0f;
-
-  Object *mirror_ob = mmd->mirror_ob;
-  if (mirror_ob != NULL) {
-    float tmp[4][4];
-    float itmp[4][4];
-
-    /* tmp is a transform from coords relative to the object's own origin,
-     * to coords relative to the mirror object origin */
-    invert_m4_m4(tmp, mirror_ob->obmat);
-    mul_m4_m4m4(tmp, tmp, ob->obmat);
-
-    /* itmp is the reverse transform back to origin-relative coordinates */
-    invert_m4_m4(itmp, tmp);
-
-    /* combine matrices to get a single matrix that translates coordinates into
-     * mirror-object-relative space, does the mirror, and translates back to
-     * origin-relative space */
-    mul_m4_series(mtx, itmp, mtx, tmp);
-
-    if (do_bisect) {
-      copy_v3_v3(plane_co, itmp[3]);
-      copy_v3_v3(plane_no, itmp[axis]);
-    }
-  }
-  else if (do_bisect) {
-    copy_v3_v3(plane_co, mtx[3]);
-    /* Need to negate here, since that axis is inverted (for mirror transform). */
-    negate_v3_v3(plane_no, mtx[axis]);
-  }
-
-  Mesh *mesh_bisect = NULL;
-  if (do_bisect) {
-    mesh_bisect = doBiscetOnMirrorPlane(mmd, mesh, axis, plane_co, plane_no);
-    mesh = mesh_bisect;
-  }
-
-  const int maxVerts = mesh->totvert;
-  const int maxEdges = mesh->totedge;
-  const int maxLoops = mesh->totloop;
-  const int maxPolys = mesh->totpoly;
-
-  result = BKE_mesh_new_nomain_from_template(
-      mesh, maxVerts * 2, maxEdges * 2, 0, maxLoops * 2, maxPolys * 2);
-
-  /*copy customdata to original geometry*/
-  CustomData_copy_data(&mesh->vdata, &result->vdata, 0, 0, maxVerts);
-  CustomData_copy_data(&mesh->edata, &result->edata, 0, 0, maxEdges);
-  CustomData_copy_data(&mesh->ldata, &result->ldata, 0, 0, maxLoops);
-  CustomData_copy_data(&mesh->pdata, &result->pdata, 0, 0, maxPolys);
-
-  /* Subsurf for eg won't have mesh data in the custom data arrays.
-   * now add mvert/medge/mpoly layers. */
-  if (!CustomData_has_layer(&mesh->vdata, CD_MVERT)) {
-    memcpy(result->mvert, mesh->mvert, sizeof(*result->mvert) * mesh->totvert);
-  }
-  if (!CustomData_has_layer(&mesh->edata, CD_MEDGE)) {
-    memcpy(result->medge, mesh->medge, sizeof(*result->medge) * mesh->totedge);
-  }
-  if (!CustomData_has_layer(&mesh->pdata, CD_MPOLY)) {
-    memcpy(result->mloop, mesh->mloop, sizeof(*result->mloop) * mesh->totloop);
-    memcpy(result->mpoly, mesh->mpoly, sizeof(*result->mpoly) * mesh->totpoly);
-  }
-
-  /* copy customdata to new geometry,
-   * copy from its self because this data may have been created in the checks above */
-  CustomData_copy_data(&result->vdata, &result->vdata, 0, maxVerts, maxVerts);
-  CustomData_copy_data(&result->edata, &result->edata, 0, maxEdges, maxEdges);
-  /* loops are copied later */
-  CustomData_copy_data(&result->pdata, &result->pdata, 0, maxPolys, maxPolys);
-
-  if (do_vtargetmap) {
-    /* second half is filled with -1 */
-    vtargetmap = MEM_malloc_arrayN(maxVerts, 2 * sizeof(int), "MOD_mirror tarmap");
-
-    vtmap_a = vtargetmap;
-    vtmap_b = vtargetmap + maxVerts;
-  }
-
-  /* mirror vertex coordinates */
-  mv_prev = result->mvert;
-  mv = mv_prev + maxVerts;
-  for (i = 0; i < maxVerts; i++, mv++, mv_prev++) {
-    mul_m4_v3(mtx, mv->co);
-
-    if (do_vtargetmap) {
-      /* compare location of the original and mirrored vertex, to see if they
-       * should be mapped for merging */
-      if (UNLIKELY(len_squared_v3v3(mv_prev->co, mv->co) < tolerance_sq)) {
-        *vtmap_a = maxVerts + i;
-        tot_vtargetmap++;
-
-        /* average location */
-        mid_v3_v3v3(mv->co, mv_prev->co, mv->co);
-        copy_v3_v3(mv_prev->co, mv->co);
-      }
-      else {
-        *vtmap_a = -1;
-      }
-
-      *vtmap_b = -1; /* fill here to avoid 2x loops */
-
-      vtmap_a++;
-      vtmap_b++;
-    }
-  }
-
-  /* handle shape keys */
-  totshape = CustomData_number_of_layers(&result->vdata, CD_SHAPEKEY);
-  for (a = 0; a < totshape; a++) {
-    float(*cos)[3] = CustomData_get_layer_n(&result->vdata, CD_SHAPEKEY, a);
-    for (i = maxVerts; i < result->totvert; i++) {
-      mul_m4_v3(mtx, cos[i]);
-    }
-  }
-
-  /* adjust mirrored edge vertex indices */
-  me = result->medge + maxEdges;
-  for (i = 0; i < maxEdges; i++, me++) {
-    me->v1 += maxVerts;
-    me->v2 += maxVerts;
-  }
-
-  /* adjust mirrored poly loopstart indices, and reverse loop order (normals) */
-  mp = result->mpoly + maxPolys;
-  ml = result->mloop;
-  for (i = 0; i < maxPolys; i++, mp++) {
-    MLoop *ml2;
-    int j, e;
-
-    /* reverse the loop, but we keep the first vertex in the face the same,
-     * to ensure that quads are split the same way as on the other side */
-    CustomData_copy_data(
-        &result->ldata, &result->ldata, mp->loopstart, mp->loopstart + maxLoops, 1);
-
-    for (j = 1; j < mp->totloop; j++) {
-      CustomData_copy_data(&result->ldata,
-                           &result->ldata,
-                           mp->loopstart + j,
-                           mp->loopstart + maxLoops + mp->totloop - j,
-                           1);
-    }
-
-    ml2 = ml + mp->loopstart + maxLoops;
-    e = ml2[0].e;
-    for (j = 0; j < mp->totloop - 1; j++) {
-      ml2[j].e = ml2[j + 1].e;
-    }
-    ml2[mp->totloop - 1].e = e;
-
-    mp->loopstart += maxLoops;
-  }
-
-  /* adjust mirrored loop vertex and edge indices */
-  ml = result->mloop + maxLoops;
-  for (i = 0; i < maxLoops; i++, ml++) {
-    ml->v += maxVerts;
-    ml->e += maxEdges;
-  }
-
-  /* handle uvs,
-   * let tessface recalc handle updating the MTFace data */
-  if (mmd->flag & (MOD_MIR_MIRROR_U | MOD_MIR_MIRROR_V) ||
-      (is_zero_v2(mmd->uv_offset_copy) == false)) {
-    const bool do_mirr_u = (mmd->flag & MOD_MIR_MIRROR_U) != 0;
-    const bool do_mirr_v = (mmd->flag & MOD_MIR_MIRROR_V) != 0;
-
-    const int totuv = CustomData_number_of_layers(&result->ldata, CD_MLOOPUV);
-
-    for (a = 0; a < totuv; a++) {
-      MLoopUV *dmloopuv = CustomData_get_layer_n(&result->ldata, CD_MLOOPUV, a);
-      int j = maxLoops;
-      dmloopuv += j; /* second set of loops only */
-      for (; j-- > 0; dmloopuv++) {
-        if (do_mirr_u) {
-          dmloopuv->uv[0] = 1.0f - dmloopuv->uv[0] + mmd->uv_offset[0];
-        }
-        if (do_mirr_v) {
-          dmloopuv->uv[1] = 1.0f - dmloopuv->uv[1] + mmd->uv_offset[1];
-        }
-        dmloopuv->uv[0] += mmd->uv_offset_copy[0];
-        dmloopuv->uv[1] += mmd->uv_offset_copy[1];
-      }
-    }
-  }
-
-  /* handle custom split normals */
-  if (ob->type == OB_MESH && (((Mesh *)ob->data)->flag & ME_AUTOSMOOTH) &&
-      CustomData_has_layer(&result->ldata, CD_CUSTOMLOOPNORMAL)) {
-    const int totloop = result->totloop;
-    const int totpoly = result->totpoly;
-    float(*loop_normals)[3] = MEM_calloc_arrayN((size_t)totloop, sizeof(*loop_normals), __func__);
-    CustomData *ldata = &result->ldata;
-    short(*clnors)[2] = CustomData_get_layer(ldata, CD_CUSTOMLOOPNORMAL);
-    MLoopNorSpaceArray lnors_spacearr = {NULL};
-    float(*poly_normals)[3] = MEM_mallocN(sizeof(*poly_normals) * totpoly, __func__);
-
-    /* calculate custom normals into loop_normals, then mirror first half into second half */
-
-    BKE_mesh_calc_normals_poly(result->mvert,
-                               NULL,
-                               result->totvert,
-                               result->mloop,
-                               result->mpoly,
-                               totloop,
-                               totpoly,
-                               poly_normals,
-                               false);
-
-    BKE_mesh_normals_loop_split(result->mvert,
-                                result->totvert,
-                                result->medge,
-                                result->totedge,
-                                result->mloop,
-                                loop_normals,
-                                totloop,
-                                result->mpoly,
-                                poly_normals,
-                                totpoly,
-                                true,
-                                mesh->smoothresh,
-                                &lnors_spacearr,
-                                clnors,
-                                NULL);
-
-    /* mirroring has to account for loops being reversed in polys in second half */
-    mp = result->mpoly;
-    for (i = 0; i < maxPolys; i++, mp++) {
-      MPoly *mpmirror = result->mpoly + maxPolys + i;
-      int j;
-
-      for (j = mp->loopstart; j < mp->loopstart + mp->totloop; j++) {
-        int mirrorj = mpmirror->loopstart;
-        if (j > mp->loopstart) {
-          mirrorj += mpmirror->totloop - (j - mp->loopstart);
-        }
-        copy_v3_v3(loop_normals[mirrorj], loop_normals[j]);
-        loop_normals[mirrorj][axis] = -loop_normals[j][axis];
-        BKE_lnor_space_custom_normal_to_data(
-            lnors_spacearr.lspacearr[mirrorj], loop_normals[mirrorj], clnors[mirrorj]);
-      }
-    }
-
-    MEM_freeN(poly_normals);
-    MEM_freeN(loop_normals);
-    BKE_lnor_spacearr_free(&lnors_spacearr);
-  }
-
-  /* handle vgroup stuff */
-  if ((mmd->flag & MOD_MIR_VGROUP) && CustomData_has_layer(&result->vdata, CD_MDEFORMVERT)) {
-    MDeformVert *dvert = (MDeformVert *)CustomData_get_layer(&result->vdata, CD_MDEFORMVERT) +
-                         maxVerts;
-    int *flip_map = NULL, flip_map_len = 0;
-
-    flip_map = defgroup_flip_map(ob, &flip_map_len, false);
-
-    if (flip_map) {
-      for (i = 0; i < maxVerts; dvert++, i++) {
-        /* merged vertices get both groups, others get flipped */
-        if (do_vtargetmap && (vtargetmap[i] != -1)) {
-          defvert_flip_merged(dvert, flip_map, flip_map_len);
-        }
-        else {
-          defvert_flip(dvert, flip_map, flip_map_len);
-        }
-      }
-
-      MEM_freeN(flip_map);
-    }
-  }
-
-  if (do_vtargetmap) {
-    /* slow - so only call if one or more merge verts are found,
-     * users may leave this on and not realize there is nothing to merge - campbell */
-    if (tot_vtargetmap) {
-      result = BKE_mesh_merge_verts(
-          result, vtargetmap, tot_vtargetmap, MESH_MERGE_VERTS_DUMP_IF_MAPPED);
-    }
-    MEM_freeN(vtargetmap);
-  }
-
-  if (mesh_bisect != NULL) {
-    BKE_id_free(NULL, mesh_bisect);
-  }
-
-  return result;
-}
-
 static Mesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
                                       const ModifierEvalContext *ctx,
                                       Object *ob,
@@ -448,11 +78,11 @@ static Mesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
 
   /* check which axes have been toggled and mirror accordingly */
   if (mmd->flag & MOD_MIR_AXIS_X) {
-    result = doMirrorOnAxis(mmd, ctx, ob, result, 0);
+    result = BKE_mirror_apply_mirror_on_axis(mmd, ctx, ob, result, 0);
   }
   if (mmd->flag & MOD_MIR_AXIS_Y) {
     Mesh *tmp = result;
-    result = doMirrorOnAxis(mmd, ctx, ob, result, 1);
+    result = BKE_mirror_apply_mirror_on_axis(mmd, ctx, ob, result, 1);
     if (tmp != mesh) {
       /* free intermediate results */
       BKE_id_free(NULL, tmp);
@@ -460,7 +90,7 @@ static Mesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
   }
   if (mmd->flag & MOD_MIR_AXIS_Z) {
     Mesh *tmp = result;
-    result = doMirrorOnAxis(mmd, ctx, ob, result, 2);
+    result = BKE_mirror_apply_mirror_on_axis(mmd, ctx, ob, result, 2);
     if (tmp != mesh) {
       /* free intermediate results */
       BKE_id_free(NULL, tmp);