text: /*
   * 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.
   */
  
  /** \file
   * \ingroup edmesh
   */
  
  #include "MEM_guardedalloc.h"
  
  #include "BLI_bitmap.h"
  #include "BLI_blenlib.h"
  #include "BLI_math.h"
  
  #include "IMB_imbuf.h"
  #include "IMB_imbuf_types.h"
  
  #include "DNA_mesh_types.h"
  #include "DNA_meshdata_types.h"
  #include "DNA_object_types.h"
  
  #include "BKE_context.h"
  #include "BKE_customdata.h"
  #include "BKE_global.h"
  #include "BKE_mesh.h"
  #include "BKE_object.h"
  
  #include "ED_mesh.h"
  #include "ED_screen.h"
  #include "ED_select_utils.h"
  #include "ED_view3d.h"
  
  #include "WM_api.h"
  #include "WM_types.h"
  
  #include "DEG_depsgraph.h"
  #include "DEG_depsgraph_query.h"
  
  /* own include */
  
  /* copy the face flags, most importantly selection from the mesh to the final derived mesh,
   * use in object mode when selecting faces (while painting) */
  void paintface_flush_flags(struct bContext *C, Object *ob, short flag)
  {
    Mesh *me = BKE_mesh_from_object(ob);
    MPoly *polys, *mp_orig;
    const int *index_array = NULL;
    int totpoly;
  
    BLI_assert((flag & ~(SELECT | ME_HIDE)) == 0);
  
    if (me == NULL) {
      return;
    }
  
    /* note, call #BKE_mesh_flush_hidden_from_verts_ex first when changing hidden flags */
  
    /* we could call this directly in all areas that change selection,
     * since this could become slow for realtime updates (circle-select for eg) */
    if (flag & SELECT) {
      BKE_mesh_flush_select_from_polys(me);
    }
  
    Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
    Object *ob_eval = DEG_get_evaluated_object(depsgraph, ob);
  
    if (ob_eval == NULL) {
      return;
    }
  
    Mesh *me_orig = (Mesh *)ob_eval->runtime.data_orig;
    Mesh *me_eval = (Mesh *)ob_eval->runtime.data_eval;
    bool updated = false;
  
    if (me_orig != NULL && me_eval != NULL && me_orig->totpoly == me->totpoly) {
      /* Update the COW copy of the mesh. */
      for (int i = 0; i < me->totpoly; i++) {
        me_orig->mpoly[i].flag = me->mpoly[i].flag;
      }
  
      /* If the mesh has only deform modifiers, the evaluated mesh shares arrays. */
      if (me_eval->mpoly == me_orig->mpoly) {
        updated = true;
      }
      /* Mesh polys => Final derived polys */
      else if ((index_array = CustomData_get_layer(&me_eval->pdata, CD_ORIGINDEX))) {
        polys = me_eval->mpoly;
        totpoly = me_eval->totpoly;
  
        /* loop over final derived polys */
        for (int i = 0; i < totpoly; i++) {
          if (index_array[i] != ORIGINDEX_NONE) {
            /* Copy flags onto the final derived poly from the original mesh poly */
            mp_orig = me->mpoly + index_array[i];
            polys[i].flag = mp_orig->flag;
          }
        }
  
        updated = true;
      }
    }
  
    if (updated) {
      if (flag & ME_HIDE) {
        BKE_mesh_batch_cache_dirty_tag(me_eval, BKE_MESH_BATCH_DIRTY_ALL);
      }
      else {
        BKE_mesh_batch_cache_dirty_tag(me_eval, BKE_MESH_BATCH_DIRTY_SELECT_PAINT);
      }
  
      DEG_id_tag_update(ob->data, ID_RECALC_SELECT);
    }
    else {
      DEG_id_tag_update(ob->data, ID_RECALC_COPY_ON_WRITE | ID_RECALC_SELECT);
    }
  
    WM_event_add_notifier(C, NC_GEOM | ND_SELECT, ob->data);
  }
  
  void paintface_hide(bContext *C, Object *ob, const bool unselected)
  {
    Mesh *me;
    MPoly *mpoly;
    int a;
  
    me = BKE_mesh_from_object(ob);
    if (me == NULL || me->totpoly == 0) {
      return;
    }
  
    mpoly = me->mpoly;
    a = me->totpoly;
    while (a--) {
      if ((mpoly->flag & ME_HIDE) == 0) {
        if (((mpoly->flag & ME_FACE_SEL) == 0) == unselected) {
          mpoly->flag |= ME_HIDE;
        }
      }
  
      if (mpoly->flag & ME_HIDE) {
        mpoly->flag &= ~ME_FACE_SEL;
      }
  
      mpoly++;
    }
  
    BKE_mesh_flush_hidden_from_polys(me);
  
    paintface_flush_flags(C, ob, SELECT | ME_HIDE);
  }
  
  void paintface_reveal(bContext *C, Object *ob, const bool select)
  {
    Mesh *me;
    MPoly *mpoly;
    int a;
  
    me = BKE_mesh_from_object(ob);
    if (me == NULL || me->totpoly == 0) {
      return;
    }
  
    mpoly = me->mpoly;
    a = me->totpoly;
    while (a--) {
      if (mpoly->flag & ME_HIDE) {
        SET_FLAG_FROM_TEST(mpoly->flag, select, ME_FACE_SEL);
        mpoly->flag &= ~ME_HIDE;
      }
      mpoly++;
    }
  
    BKE_mesh_flush_hidden_from_polys(me);
  
    paintface_flush_flags(C, ob, SELECT | ME_HIDE);
  }
  
  /* Set tface seams based on edge data, uses hash table to find seam edges. */
  
  static void select_linked_tfaces_with_seams(Mesh *me, const uint index, const bool select)
  {
    MPoly *mp;
    MLoop *ml;
    int a, b;
    bool do_it = true;
    bool mark = false;
  
    BLI_bitmap *edge_tag = BLI_BITMAP_NEW(me->totedge, __func__);
    BLI_bitmap *poly_tag = BLI_BITMAP_NEW(me->totpoly, __func__);
  
    if (index != (uint)-1) {
      /* only put face under cursor in array */
      mp = &me->mpoly[index];
      BKE_mesh_poly_edgebitmap_insert(edge_tag, mp, me->mloop + mp->loopstart);
      BLI_BITMAP_ENABLE(poly_tag, index);
    }
    else {
      /* fill array by selection */
      mp = me->mpoly;
      for (a = 0; a < me->totpoly; a++, mp++) {
        if (mp->flag & ME_HIDE) {
          /* pass */
        }
        else if (mp->flag & ME_FACE_SEL) {
          BKE_mesh_poly_edgebitmap_insert(edge_tag, mp, me->mloop + mp->loopstart);
          BLI_BITMAP_ENABLE(poly_tag, a);
        }
      }
    }
  
    while (do_it) {
      do_it = false;
  
      /* expand selection */
      mp = me->mpoly;
      for (a = 0; a < me->totpoly; a++, mp++) {
        if (mp->flag & ME_HIDE) {
          continue;
        }
  
        if (!BLI_BITMAP_TEST(poly_tag, a)) {
          mark = false;
  
          ml = me->mloop + mp->loopstart;
          for (b = 0; b < mp->totloop; b++, ml++) {
            if ((me->medge[ml->e].flag & ME_SEAM) == 0) {
              if (BLI_BITMAP_TEST(edge_tag, ml->e)) {
                mark = true;
                break;
              }
            }
          }
  
          if (mark) {
            BLI_BITMAP_ENABLE(poly_tag, a);
            BKE_mesh_poly_edgebitmap_insert(edge_tag, mp, me->mloop + mp->loopstart);
            do_it = true;
          }
        }
      }
    }
  
    MEM_freeN(edge_tag);
  
    for (a = 0, mp = me->mpoly; a < me->totpoly; a++, mp++) {
      if (BLI_BITMAP_TEST(poly_tag, a)) {
        SET_FLAG_FROM_TEST(mp->flag, select, ME_FACE_SEL);
      }
    }
  
    MEM_freeN(poly_tag);
  }
  
  void paintface_select_linked(bContext *C, Object *ob, const int mval[2], const bool select)
  {
    Mesh *me;
    uint index = (uint)-1;
  
    me = BKE_mesh_from_object(ob);
    if (me == NULL || me->totpoly == 0) {
      return;
    }
  
    if (mval) {
      if (!ED_mesh_pick_face(C, ob, mval, ED_MESH_PICK_DEFAULT_FACE_DIST, &index)) {
        return;
      }
    }
  
    select_linked_tfaces_with_seams(me, index, select);
  
    paintface_flush_flags(C, ob, SELECT);
  }
  
  bool paintface_deselect_all_visible(bContext *C, Object *ob, int action, bool flush_flags)
  {
    Mesh *me;
    MPoly *mpoly;
    int a;
  
    me = BKE_mesh_from_object(ob);
    if (me == NULL) {
      return false;
    }
  
    if (action == SEL_TOGGLE) {
      action = SEL_SELECT;
  
      mpoly = me->mpoly;
      a = me->totpoly;
      while (a--) {
        if ((mpoly->flag & ME_HIDE) == 0 && mpoly->flag & ME_FACE_SEL) {
          action = SEL_DESELECT;
          break;
        }
        mpoly++;
      }
    }
  
    bool changed = false;
  
    mpoly = me->mpoly;
    a = me->totpoly;
    while (a--) {
      if ((mpoly->flag & ME_HIDE) == 0) {
        switch (action) {
          case SEL_SELECT:
            if ((mpoly->flag & ME_FACE_SEL) == 0) {
              mpoly->flag |= ME_FACE_SEL;
              changed = true;
            }
            break;
          case SEL_DESELECT:
            if ((mpoly->flag & ME_FACE_SEL) != 0) {
              mpoly->flag &= ~ME_FACE_SEL;
              changed = true;
            }
            break;
          case SEL_INVERT:
            mpoly->flag ^= ME_FACE_SEL;
            changed = true;
            break;
        }
      }
      mpoly++;
    }
  
    if (changed) {
      if (flush_flags) {
        paintface_flush_flags(C, ob, SELECT);
      }
    }
    return changed;
  }
  
  bool paintface_minmax(Object *ob, float r_min[3], float r_max[3])
  {
    const Mesh *me;
    const MPoly *mp;
    const MLoop *ml;
    const MVert *mvert;
    int a, b;
    bool ok = false;
    float vec[3], bmat[3][3];
  
    me = BKE_mesh_from_object(ob);
    if (!me || !me->mloopuv) {
      return ok;
    }
  
    copy_m3_m4(bmat, ob->obmat);
  
    mvert = me->mvert;
    mp = me->mpoly;
    for (a = me->totpoly; a > 0; a--, mp++) {
      if (mp->flag & ME_HIDE || !(mp->flag & ME_FACE_SEL)) {
        continue;
      }
  
      ml = me->mloop + mp->totloop;
      for (b = 0; b < mp->totloop; b++, ml++) {
        mul_v3_m3v3(vec, bmat, mvert[ml->v].co);
        add_v3_v3v3(vec, vec, ob->obmat[3]);
        minmax_v3v3_v3(r_min, r_max, vec);
      }
  
      ok = true;
    }
  
    return ok;
  }
  
  bool paintface_mouse_select(
      struct bContext *C, Object *ob, const int mval[2], bool extend, bool deselect, bool toggle)
  {
    Mesh *me;
    MPoly *mpoly_sel;
    uint index;
  
    /* Get the face under the cursor */
    me = BKE_mesh_from_object(ob);
  
    if (!ED_mesh_pick_face(C, ob, mval, ED_MESH_PICK_DEFAULT_FACE_DIST, &index)) {
      return false;
    }
  
    if (index >= me->totpoly) {
      return false;
    }
  
    mpoly_sel = me->mpoly + index;
    if (mpoly_sel->flag & ME_HIDE) {
      return false;
    }
  
    /* clear flags */
    if (!extend && !deselect && !toggle) {
      paintface_deselect_all_visible(C, ob, SEL_DESELECT, false);
    }
  
    me->act_face = (int)index;
  
    if (extend) {
      mpoly_sel->flag |= ME_FACE_SEL;
    }
    else if (deselect) {
      mpoly_sel->flag &= ~ME_FACE_SEL;
    }
    else if (toggle) {
      if (mpoly_sel->flag & ME_FACE_SEL) {
        mpoly_sel->flag &= ~ME_FACE_SEL;
      }
      else {
        mpoly_sel->flag |= ME_FACE_SEL;
      }
    }
    else {
      mpoly_sel->flag |= ME_FACE_SEL;
    }
  
    /* image window redraw */
  
    paintface_flush_flags(C, ob, SELECT);
    ED_region_tag_redraw(CTX_wm_region(C)); /* XXX - should redraw all 3D views */
    return true;
  }
  
  /*  (similar to void paintface_flush_flags(Object *ob))
   * copy the vertex flags, most importantly selection from the mesh to the final derived mesh,
   * use in object mode when selecting vertices (while painting) */
  void paintvert_flush_flags(Object *ob)
  {
    Mesh *me = BKE_mesh_from_object(ob);
    Mesh *me_eval = BKE_object_get_evaluated_mesh(ob);
    MVert *mvert_eval, *mv;
    const int *index_array = NULL;
    int totvert;
    int i;
  
    if (me == NULL) {
      return;
    }
  
    /* we could call this directly in all areas that change selection,
     * since this could become slow for realtime updates (circle-select for eg) */
    BKE_mesh_flush_select_from_verts(me);
  
    if (me_eval == NULL) {
      return;
    }
  
    index_array = CustomData_get_layer(&me_eval->vdata, CD_ORIGINDEX);
  
    mvert_eval = me_eval->mvert;
    totvert = me_eval->totvert;
  
    mv = mvert_eval;
  
    if (index_array) {
      int orig_index;
      for (i = 0; i < totvert; i++, mv++) {
        orig_index = index_array[i];
        if (orig_index != ORIGINDEX_NONE) {
          mv->flag = me->mvert[index_array[i]].flag;
        }
      }
    }
    else {
      for (i = 0; i < totvert; i++, mv++) {
        mv->flag = me->mvert[i].flag;
      }
    }
  
    BKE_mesh_batch_cache_dirty_tag(me, BKE_MESH_BATCH_DIRTY_ALL);
  }
  
  void paintvert_tag_select_update(struct bContext *C, struct Object *ob)
  {
    DEG_id_tag_update(ob->data, ID_RECALC_COPY_ON_WRITE | ID_RECALC_SELECT);
    WM_event_add_notifier(C, NC_GEOM | ND_SELECT, ob->data);
  }
  
  /**
   * \note if the caller passes false to flush_flags,
   * then they will need to run #paintvert_flush_flags(ob) themselves.
   */
  bool paintvert_deselect_all_visible(Object *ob, int action, bool flush_flags)
  {
    Mesh *me;
    MVert *mvert;
    int a;
  
    me = BKE_mesh_from_object(ob);
    if (me == NULL) {
      return false;
    }
  
    if (action == SEL_TOGGLE) {
      action = SEL_SELECT;
  
      mvert = me->mvert;
      a = me->totvert;
      while (a--) {
        if ((mvert->flag & ME_HIDE) == 0 && mvert->flag & SELECT) {
          action = SEL_DESELECT;
          break;
        }
        mvert++;
      }
    }
  
    bool changed = false;
    mvert = me->mvert;
    a = me->totvert;
    while (a--) {
      if ((mvert->flag & ME_HIDE) == 0) {
        switch (action) {
          case SEL_SELECT:
            if ((mvert->flag & SELECT) == 0) {
              mvert->flag |= SELECT;
              changed = true;
            }
            break;
          case SEL_DESELECT:
            if ((mvert->flag & SELECT) != 0) {
              mvert->flag &= ~SELECT;
              changed = true;
            }
            break;
          case SEL_INVERT:
            mvert->flag ^= SELECT;
            changed = true;
            break;
        }
      }
      mvert++;
    }
  
    if (changed) {
      /* handle mselect */
      if (action == SEL_SELECT) {
        /* pass */
      }
      else if (ELEM(action, SEL_DESELECT, SEL_INVERT)) {
        BKE_mesh_mselect_clear(me);
      }
      else {
        BKE_mesh_mselect_validate(me);
      }
  
      if (flush_flags) {
        paintvert_flush_flags(ob);
      }
    }
    return changed;
  }
  
  void paintvert_select_ungrouped(Object *ob, bool extend, bool flush_flags)
  {
    Mesh *me = BKE_mesh_from_object(ob);
    MVert *mv;
    MDeformVert *dv;
    int a, tot;
  
    if (me == NULL || me->dvert == NULL) {
      return;
    }
  
    if (!extend) {
      paintvert_deselect_all_visible(ob, SEL_DESELECT, false);
    }
  
    dv = me->dvert;
    tot = me->totvert;
  
    for (a = 0, mv = me->mvert; a < tot; a++, mv++, dv++) {
      if ((mv->flag & ME_HIDE) == 0) {
        if (dv->dw == NULL) {
          /* if null weight then not grouped */
          mv->flag |= SELECT;
        }
      }
    }
  
    if (flush_flags) {
      paintvert_flush_flags(ob);
    }
  }
  