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.
   *
   * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
   * All rights reserved.
   */
  
  /** \file
   * \ingroup bke
   */
  
  #include <stdio.h>
  #include <string.h>
  #include <math.h>
  #include <stdlib.h>
  #include <wctype.h>
  
  #include "CLG_log.h"
  
  #include "MEM_guardedalloc.h"
  
  #include "BLI_utildefines.h"
  #include "BLI_path_util.h"
  #include "BLI_listbase.h"
  #include "BLI_ghash.h"
  #include "BLI_string.h"
  #include "BLI_string_utf8.h"
  #include "BLI_math.h"
  #include "BLI_threads.h"
  #include "BLI_vfontdata.h"
  
  #include "DNA_packedFile_types.h"
  #include "DNA_curve_types.h"
  #include "DNA_vfont_types.h"
  #include "DNA_object_types.h"
  
  #include "BKE_packedFile.h"
  #include "BKE_lib_id.h"
  #include "BKE_font.h"
  #include "BKE_global.h"
  #include "BKE_main.h"
  #include "BKE_anim.h"
  #include "BKE_curve.h"
  
  static CLG_LogRef LOG = {"bke.data_transfer"};
  static ThreadRWMutex vfont_rwlock = BLI_RWLOCK_INITIALIZER;
  
  /* The vfont code */
  void BKE_vfont_free_data(struct VFont *vfont)
  {
    if (vfont->data) {
      if (vfont->data->characters) {
        GHashIterator gh_iter;
        GHASH_ITER (gh_iter, vfont->data->characters) {
          VChar *che = BLI_ghashIterator_getValue(&gh_iter);
  
          while (che->nurbsbase.first) {
            Nurb *nu = che->nurbsbase.first;
            if (nu->bezt) {
              MEM_freeN(nu->bezt);
            }
            BLI_freelinkN(&che->nurbsbase, nu);
          }
  
          MEM_freeN(che);
        }
  
        BLI_ghash_free(vfont->data->characters, NULL, NULL);
      }
  
      MEM_freeN(vfont->data);
      vfont->data = NULL;
    }
  
    if (vfont->temp_pf) {
      BKE_packedfile_free(vfont->temp_pf); /* NULL when the font file can't be found on disk */
      vfont->temp_pf = NULL;
    }
  }
  
  /** Free (or release) any data used by this font (does not free the font itself). */
  void BKE_vfont_free(struct VFont *vf)
  {
    BKE_vfont_free_data(vf);
  
    if (vf->packedfile) {
      BKE_packedfile_free(vf->packedfile);
      vf->packedfile = NULL;
    }
  }
  
  void BKE_vfont_copy_data(Main *UNUSED(bmain),
                           VFont *vfont_dst,
                           const VFont *UNUSED(vfont_src),
                           const int flag)
  {
    /* We never handle usercount here for own data. */
    const int flag_subdata = flag | LIB_ID_CREATE_NO_USER_REFCOUNT;
  
    /* Just to be sure, should not have any value actually after reading time. */
    vfont_dst->temp_pf = NULL;
  
    if (vfont_dst->packedfile) {
      vfont_dst->packedfile = BKE_packedfile_duplicate(vfont_dst->packedfile);
    }
  
    if (vfont_dst->data) {
      vfont_dst->data = BLI_vfontdata_copy(vfont_dst->data, flag_subdata);
    }
  }
  
  static void *builtin_font_data = NULL;
  static int builtin_font_size = 0;
  
  bool BKE_vfont_is_builtin(struct VFont *vfont)
  {
    return STREQ(vfont->name, FO_BUILTIN_NAME);
  }
  
  void BKE_vfont_builtin_register(void *mem, int size)
  {
    builtin_font_data = mem;
    builtin_font_size = size;
  }
  
  static PackedFile *get_builtin_packedfile(void)
  {
    if (!builtin_font_data) {
      CLOG_ERROR(&LOG, "Internal error, builtin font not loaded");
  
      return NULL;
    }
    else {
      void *mem = MEM_mallocN(builtin_font_size, "vfd_builtin");
  
      memcpy(mem, builtin_font_data, builtin_font_size);
  
      return BKE_packedfile_new_from_memory(mem, builtin_font_size);
    }
  }
  
  static VFontData *vfont_get_data(VFont *vfont)
  {
    if (vfont == NULL) {
      return NULL;
    }
  
    /* And then set the data */
    if (!vfont->data) {
      PackedFile *pf;
  
      BLI_rw_mutex_lock(&vfont_rwlock, THREAD_LOCK_WRITE);
  
      if (vfont->data) {
        /* Check data again, since it might have been already
         * initialized from other thread (previous check is
         * not accurate or threading, just prevents unneeded
         * lock if all the data is here for sure).
         */
        BLI_rw_mutex_unlock(&vfont_rwlock);
        return vfont->data;
      }
  
      if (BKE_vfont_is_builtin(vfont)) {
        pf = get_builtin_packedfile();
      }
      else {
        if (vfont->packedfile) {
          pf = vfont->packedfile;
  
          /* We need to copy a tmp font to memory unless it is already there */
          if (vfont->temp_pf == NULL) {
            vfont->temp_pf = BKE_packedfile_duplicate(pf);
          }
        }
        else {
          pf = BKE_packedfile_new(NULL, vfont->name, ID_BLEND_PATH_FROM_GLOBAL(&vfont->id));
  
          if (vfont->temp_pf == NULL) {
            vfont->temp_pf = BKE_packedfile_new(
                NULL, vfont->name, ID_BLEND_PATH_FROM_GLOBAL(&vfont->id));
          }
        }
        if (!pf) {
          CLOG_WARN(&LOG, "Font file doesn't exist: %s", vfont->name);
  
          /* DON'T DO THIS
           * missing file shouldn't modify path! - campbell */
  #if 0
          strcpy(vfont->name, FO_BUILTIN_NAME);
  #endif
          pf = get_builtin_packedfile();
        }
      }
  
      if (pf) {
        vfont->data = BLI_vfontdata_from_freetypefont(pf);
        if (pf != vfont->packedfile) {
          BKE_packedfile_free(pf);
        }
      }
  
      BLI_rw_mutex_unlock(&vfont_rwlock);
    }
  
    return vfont->data;
  }
  
  /* Bad naming actually in this case... */
  void BKE_vfont_init(VFont *vfont)
  {
    PackedFile *pf = get_builtin_packedfile();
  
    if (pf) {
      VFontData *vfd;
  
      vfd = BLI_vfontdata_from_freetypefont(pf);
      if (vfd) {
        vfont->data = vfd;
  
        BLI_strncpy(vfont->name, FO_BUILTIN_NAME, sizeof(vfont->name));
      }
  
      /* Free the packed file */
      BKE_packedfile_free(pf);
    }
  }
  
  VFont *BKE_vfont_load(Main *bmain, const char *filepath)
  {
    char filename[FILE_MAXFILE];
    VFont *vfont = NULL;
    PackedFile *pf;
    bool is_builtin;
  
    if (STREQ(filepath, FO_BUILTIN_NAME)) {
      BLI_strncpy(filename, filepath, sizeof(filename));
  
      pf = get_builtin_packedfile();
      is_builtin = true;
    }
    else {
      BLI_split_file_part(filepath, filename, sizeof(filename));
      pf = BKE_packedfile_new(NULL, filepath, BKE_main_blendfile_path(bmain));
  
      is_builtin = false;
    }
  
    if (pf) {
      VFontData *vfd;
  
      vfd = BLI_vfontdata_from_freetypefont(pf);
      if (vfd) {
        vfont = BKE_libblock_alloc(bmain, ID_VF, filename, 0);
        vfont->data = vfd;
  
        /* if there's a font name, use it for the ID name */
        if (vfd->name[0] != '\0') {
          BLI_strncpy(vfont->id.name + 2, vfd->name, sizeof(vfont->id.name) - 2);
        }
        BLI_strncpy(vfont->name, filepath, sizeof(vfont->name));
  
        /* if autopack is on store the packedfile in de font structure */
        if (!is_builtin && (G.fileflags & G_FILE_AUTOPACK)) {
          vfont->packedfile = pf;
        }
  
        /* Do not add FO_BUILTIN_NAME to temporary listbase */
        if (!STREQ(filename, FO_BUILTIN_NAME)) {
          vfont->temp_pf = BKE_packedfile_new(NULL, filepath, BKE_main_blendfile_path(bmain));
        }
      }
  
      /* Free the packed file */
      if (!vfont || vfont->packedfile != pf) {
        BKE_packedfile_free(pf);
      }
    }
  
    return vfont;
  }
  
  VFont *BKE_vfont_load_exists_ex(struct Main *bmain, const char *filepath, bool *r_exists)
  {
    VFont *vfont;
    char str[FILE_MAX], strtest[FILE_MAX];
  
    BLI_strncpy(str, filepath, sizeof(str));
    BLI_path_abs(str, BKE_main_blendfile_path(bmain));
  
    /* first search an identical filepath */
    for (vfont = bmain->fonts.first; vfont; vfont = vfont->id.next) {
      BLI_strncpy(strtest, vfont->name, sizeof(vfont->name));
      BLI_path_abs(strtest, ID_BLEND_PATH(bmain, &vfont->id));
  
      if (BLI_path_cmp(strtest, str) == 0) {
        id_us_plus(&vfont->id); /* officially should not, it doesn't link here! */
        if (r_exists) {
          *r_exists = true;
        }
        return vfont;
      }
    }
  
    if (r_exists) {
      *r_exists = false;
    }
    return BKE_vfont_load(bmain, filepath);
  }
  
  VFont *BKE_vfont_load_exists(struct Main *bmain, const char *filepath)
  {
    return BKE_vfont_load_exists_ex(bmain, filepath, NULL);
  }
  
  void BKE_vfont_make_local(Main *bmain, VFont *vfont, const int flags)
  {
    BKE_lib_id_make_local_generic(bmain, &vfont->id, flags);
  }
  
  static VFont *which_vfont(Curve *cu, CharInfo *info)
  {
    switch (info->flag & (CU_CHINFO_BOLD | CU_CHINFO_ITALIC)) {
      case CU_CHINFO_BOLD:
        return cu->vfontb ? cu->vfontb : cu->vfont;
      case CU_CHINFO_ITALIC:
        return cu->vfonti ? cu->vfonti : cu->vfont;
      case (CU_CHINFO_BOLD | CU_CHINFO_ITALIC):
        return cu->vfontbi ? cu->vfontbi : cu->vfont;
      default:
        return cu->vfont;
    }
  }
  
  VFont *BKE_vfont_builtin_get(void)
  {
    VFont *vfont;
  
    for (vfont = G_MAIN->fonts.first; vfont; vfont = vfont->id.next) {
      if (BKE_vfont_is_builtin(vfont)) {
        return vfont;
      }
    }
  
    return BKE_vfont_load(G_MAIN, FO_BUILTIN_NAME);
  }
  
  static VChar *find_vfont_char(VFontData *vfd, unsigned int character)
  {
    return BLI_ghash_lookup(vfd->characters, POINTER_FROM_UINT(character));
  }
  
  static void build_underline(Curve *cu,
                              ListBase *nubase,
                              const rctf *rect,
                              float yofs,
                              float rot,
                              int charidx,
                              short mat_nr,
                              const float font_size)
  {
    Nurb *nu2;
    BPoint *bp;
  
    nu2 = (Nurb *)MEM_callocN(sizeof(Nurb), "underline_nurb");
    nu2->resolu = cu->resolu;
    nu2->bezt = NULL;
    nu2->knotsu = nu2->knotsv = NULL;
    nu2->flag = CU_2D;
    nu2->charidx = charidx + 1000;
    if (mat_nr > 0) {
      nu2->mat_nr = mat_nr - 1;
    }
    nu2->pntsu = 4;
    nu2->pntsv = 1;
    nu2->orderu = 4;
    nu2->orderv = 1;
    nu2->flagu = CU_NURB_CYCLIC;
  
    bp = (BPoint *)MEM_calloc_arrayN(4, sizeof(BPoint), "underline_bp");
  
    copy_v4_fl4(bp[0].vec, rect->xmin, (rect->ymax + yofs), 0.0f, 1.0f);
    copy_v4_fl4(bp[1].vec, rect->xmax, (rect->ymax + yofs), 0.0f, 1.0f);
    copy_v4_fl4(bp[2].vec, rect->xmax, (rect->ymin + yofs), 0.0f, 1.0f);
    copy_v4_fl4(bp[3].vec, rect->xmin, (rect->ymin + yofs), 0.0f, 1.0f);
  
    /* Used by curve extrusion. */
    bp[0].radius = bp[1].radius = bp[2].radius = bp[3].radius = 1.0f;
  
    nu2->bp = bp;
    BLI_addtail(nubase, nu2);
  
    if (rot != 0.0f) {
      float si, co;
      int i;
  
      si = sinf(rot);
      co = cosf(rot);
  
      for (i = nu2->pntsu; i > 0; i--) {
        float *fp;
        float x, y;
  
        fp = bp->vec;
  
        x = fp[0] - rect->xmin;
        y = fp[1] - rect->ymin;
  
        fp[0] = (+co * x + si * y) + rect->xmin;
        fp[1] = (-si * x + co * y) + rect->ymin;
  
        bp++;
      }
  
      bp = nu2->bp;
    }
  
    mul_v2_fl(bp[0].vec, font_size);
    mul_v2_fl(bp[1].vec, font_size);
    mul_v2_fl(bp[2].vec, font_size);
    mul_v2_fl(bp[3].vec, font_size);
  }
  
  static void buildchar(Curve *cu,
                        ListBase *nubase,
                        unsigned int character,
                        CharInfo *info,
                        float ofsx,
                        float ofsy,
                        float rot,
                        int charidx,
                        const float fsize)
  {
    BezTriple *bezt1, *bezt2;
    Nurb *nu1 = NULL, *nu2 = NULL;
    float *fp, shear, x, si, co;
    VFontData *vfd = NULL;
    VChar *che = NULL;
    int i;
  
    vfd = vfont_get_data(which_vfont(cu, info));
    if (!vfd) {
      return;
    }
  
    /* make a copy at distance ofsx, ofsy with shear */
    shear = cu->shear;
    si = sinf(rot);
    co = cosf(rot);
  
    che = find_vfont_char(vfd, character);
  
    /* Select the glyph data */
    if (che) {
      nu1 = che->nurbsbase.first;
    }
  
    /* Create the character */
    while (nu1) {
      bezt1 = nu1->bezt;
      if (bezt1) {
        nu2 = (Nurb *)MEM_mallocN(sizeof(Nurb), "duplichar_nurb");
        if (nu2 == NULL) {
          break;
        }
        memcpy(nu2, nu1, sizeof(struct Nurb));
        nu2->resolu = cu->resolu;
        nu2->bp = NULL;
        nu2->knotsu = nu2->knotsv = NULL;
        nu2->flag = CU_SMOOTH;
        nu2->charidx = charidx;
        if (info->mat_nr > 0) {
          nu2->mat_nr = info->mat_nr - 1;
        }
        else {
          nu2->mat_nr = 0;
        }
        /* nu2->trim.first = 0; */
        /* nu2->trim.last = 0; */
        i = nu2->pntsu;
  
        bezt2 = (BezTriple *)MEM_malloc_arrayN(i, sizeof(BezTriple), "duplichar_bezt2");
        if (bezt2 == NULL) {
          MEM_freeN(nu2);
          break;
        }
        memcpy(bezt2, bezt1, i * sizeof(struct BezTriple));
        nu2->bezt = bezt2;
  
        if (shear != 0.0f) {
          bezt2 = nu2->bezt;
  
          for (i = nu2->pntsu; i > 0; i--) {
            bezt2->vec[0][0] += shear * bezt2->vec[0][1];
            bezt2->vec[1][0] += shear * bezt2->vec[1][1];
            bezt2->vec[2][0] += shear * bezt2->vec[2][1];
            bezt2++;
          }
        }
        if (rot != 0.0f) {
          bezt2 = nu2->bezt;
          for (i = nu2->pntsu; i > 0; i--) {
            fp = bezt2->vec[0];
  
            x = fp[0];
            fp[0] = co * x + si * fp[1];
            fp[1] = -si * x + co * fp[1];
            x = fp[3];
            fp[3] = co * x + si * fp[4];
            fp[4] = -si * x + co * fp[4];
            x = fp[6];
            fp[6] = co * x + si * fp[7];
            fp[7] = -si * x + co * fp[7];
  
            bezt2++;
          }
        }
        bezt2 = nu2->bezt;
  
        if (info->flag & CU_CHINFO_SMALLCAPS_CHECK) {
          const float sca = cu->smallcaps_scale;
          for (i = nu2->pntsu; i > 0; i--) {
            fp = bezt2->vec[0];
            fp[0] *= sca;
            fp[1] *= sca;
            fp[3] *= sca;
            fp[4] *= sca;
            fp[6] *= sca;
            fp[7] *= sca;
            bezt2++;
          }
        }
        bezt2 = nu2->bezt;
  
        for (i = nu2->pntsu; i > 0; i--) {
          fp = bezt2->vec[0];
          fp[0] = (fp[0] + ofsx) * fsize;
          fp[1] = (fp[1] + ofsy) * fsize;
          fp[3] = (fp[3] + ofsx) * fsize;
          fp[4] = (fp[4] + ofsy) * fsize;
          fp[6] = (fp[6] + ofsx) * fsize;
          fp[7] = (fp[7] + ofsy) * fsize;
          bezt2++;
        }
  
        BLI_addtail(nubase, nu2);
      }
  
      nu1 = nu1->next;
    }
  }
  
  int BKE_vfont_select_get(Object *ob, int *r_start, int *r_end)
  {
    Curve *cu = ob->data;
    EditFont *ef = cu->editfont;
    int start, end, direction;
  
    if ((ob->type != OB_FONT) || (ef == NULL)) {
      return 0;
    }
  
    BLI_assert(ef->len >= 0);
    BLI_assert(ef->selstart >= 0 && ef->selstart <= ef->len + 1);
    BLI_assert(ef->selend >= 0 && ef->selend <= ef->len + 1);
    BLI_assert(ef->pos >= 0 && ef->pos <= ef->len);
  
    if (ef->selstart == 0) {
      return 0;
    }
  
    if (ef->selstart <= ef->selend) {
      start = ef->selstart - 1;
      end = ef->selend - 1;
      direction = 1;
    }
    else {
      start = ef->selend;
      end = ef->selstart - 2;
      direction = -1;
    }
  
    if (start == end + 1) {
      return 0;
    }
    else {
      BLI_assert(start < end + 1);
      *r_start = start;
      *r_end = end;
      return direction;
    }
  }
  
  void BKE_vfont_select_clamp(Object *ob)
  {
    Curve *cu = ob->data;
    EditFont *ef = cu->editfont;
  
    BLI_assert((ob->type == OB_FONT) && ef);
  
    CLAMP_MAX(ef->pos, ef->len);
    CLAMP_MAX(ef->selstart, ef->len + 1);
    CLAMP_MAX(ef->selend, ef->len);
  }
  
  static float char_width(Curve *cu, VChar *che, CharInfo *info)
  {
    /* The character wasn't found, probably ascii = 0, then the width shall be 0 as well */
    if (che == NULL) {
      return 0.0f;
    }
    else if (info->flag & CU_CHINFO_SMALLCAPS_CHECK) {
      return che->width * cu->smallcaps_scale;
    }
    else {
      return che->width;
    }
  }
  
  static void textbox_scale(TextBox *tb_dst, const TextBox *tb_src, float scale)
  {
    tb_dst->x = tb_src->x * scale;
    tb_dst->y = tb_src->y * scale;
    tb_dst->w = tb_src->w * scale;
    tb_dst->h = tb_src->h * scale;
  }
  
  /**
   * Used for storing per-line data for alignment & wrapping.
   */
  struct TempLineInfo {
    float x_min;   /* left margin */
    float x_max;   /* right margin */
    int char_nr;   /* number of characters */
    int wspace_nr; /* number of whitespaces of line */
  };
  
  typedef struct VFontToCurveIter {
    int iteraction;
    float scale_to_fit;
    struct {
      float min;
      float max;
    } bisect;
    bool ok;
    int status;
  } VFontToCurveIter;
  
  enum {
    VFONT_TO_CURVE_INIT = 0,
    VFONT_TO_CURVE_BISECT,
    VFONT_TO_CURVE_SCALE_ONCE,
    VFONT_TO_CURVE_DONE,
  };
  
  #define FONT_TO_CURVE_SCALE_ITERATIONS 20
  #define FONT_TO_CURVE_SCALE_THRESHOLD 0.0001f
  
  /**
   * Font metric values explained:
   *
   * Baseline: Line where the text "rests", used as the origin vertical position for the glyphs.
   * Em height: Space most glyphs should fit within.
   * Ascent: the recommended distance above the baseline to fit most characters.
   * Descent: the recommended distance below the baseline to fit most characters.
   *
   * We obtain ascent and descent from the font itself (FT_Face->ascender / face->height).
   * And in some cases it is even the same value as FT_Face->bbox.yMax/yMin
   * (font top and bottom respectively).
   *
   * The em_height here is relative to FT_Face->bbox.
   */
  #define ASCENT(vfd) ((vfd)->ascender * (vfd)->em_height)
  #define DESCENT(vfd) ((vfd)->em_height - ASCENT(vfd))
  
  static bool vfont_to_curve(Object *ob,
                             Curve *cu,
                             int mode,
                             VFontToCurveIter *iter_data,
                             ListBase *r_nubase,
                             const char32_t **r_text,
                             int *r_text_len,
                             bool *r_text_free,
                             struct CharTrans **r_chartransdata)
  {
    EditFont *ef = cu->editfont;
    EditFontSelBox *selboxes = NULL;
    VFont *vfont, *oldvfont;
    VFontData *vfd = NULL;
    CharInfo *info = NULL, *custrinfo;
    TextBox tb_scale;
    bool use_textbox;
    VChar *che;
    struct CharTrans *chartransdata = NULL, *ct;
    struct TempLineInfo *lineinfo;
    float *f, xof, yof, xtrax, linedist;
    float twidth = 0, maxlen = 0;
    int i, slen, j;
    int curbox;
    int selstart, selend;
    int cnr = 0, lnr = 0, wsnr = 0;
    const char32_t *mem = NULL;
    char32_t ascii;
    bool ok = false;
    const float font_size = cu->fsize * iter_data->scale_to_fit;
    const float xof_scale = cu->xof / font_size;
    const float yof_scale = cu->yof / font_size;
    int last_line = -1;
    /* Length of the text disregarding \n breaks. */
    float current_line_length = 0.0f;
    float longest_line_length = 0.0f;
  
    /* Text at the beginning of the last used text-box (use for y-axis alignment).
     * We overallocate by one to simplify logic of getting last char. */
    int *i_textbox_array = MEM_callocN(sizeof(*i_textbox_array) * (cu->totbox + 1),
                                       "TextBox initial char index");
  
  #define MARGIN_X_MIN (xof_scale + tb_scale.x)
  #define MARGIN_Y_MIN (yof_scale + tb_scale.y)
  
    /* remark: do calculations including the trailing '\0' of a string
     * because the cursor can be at that location */
  
    BLI_assert(ob == NULL || ob->type == OB_FONT);
  
    /* Set font data */
    vfont = cu->vfont;
  
    if (cu->str == NULL) {
      return ok;
    }
    if (vfont == NULL) {
      return ok;
    }
  
    vfd = vfont_get_data(vfont);
  
    /* The VFont Data can not be found */
    if (!vfd) {
      return ok;
    }
  
    if (ef) {
      slen = ef->len;
      mem = ef->textbuf;
      custrinfo = ef->textbufinfo;
    }
    else {
      char32_t *mem_tmp;
      slen = cu->len_wchar;
  
      /* Create unicode string */
      mem_tmp = MEM_malloc_arrayN((slen + 1), sizeof(*mem_tmp), "convertedmem");
      if (!mem_tmp) {
        return ok;
      }
  
      BLI_str_utf8_as_utf32(mem_tmp, cu->str, slen + 1);
  
      if (cu->strinfo == NULL) { /* old file */
        cu->strinfo = MEM_calloc_arrayN((slen + 4), sizeof(CharInfo), "strinfo compat");
      }
      custrinfo = cu->strinfo;
      if (!custrinfo) {
        return ok;
      }
  
      mem = mem_tmp;
    }
  
    if (cu->tb == NULL) {
      cu->tb = MEM_calloc_arrayN(MAXTEXTBOX, sizeof(TextBox), "TextBox compat");
    }
  
    if (ef != NULL && ob != NULL) {
      if (ef->selboxes) {
        MEM_freeN(ef->selboxes);
      }
  
      if (BKE_vfont_select_get(ob, &selstart, &selend)) {
        ef->selboxes_len = (selend - selstart) + 1;
        ef->selboxes = MEM_calloc_arrayN(ef->selboxes_len, sizeof(EditFontSelBox), "font selboxes");
      }
      else {
        ef->selboxes_len = 0;
        ef->selboxes = NULL;
      }
  
      selboxes = ef->selboxes;
    }
  
    /* calc offset and rotation of each char */
    ct = chartransdata = MEM_calloc_arrayN((slen + 1), sizeof(struct CharTrans), "buildtext");
  
    /* We assume the worst case: 1 character per line (is freed at end anyway) */
    lineinfo = MEM_malloc_arrayN((slen * 2 + 1), sizeof(*lineinfo), "lineinfo");
  
    linedist = cu->linedist;
  
    curbox = 0;
    textbox_scale(&tb_scale, &cu->tb[curbox], 1.0f / font_size);
    use_textbox = (tb_scale.w != 0.0f);
  
    xof = MARGIN_X_MIN;
    yof = MARGIN_Y_MIN;
  
    xtrax = 0.5f * cu->spacing - 0.5f;
  
    oldvfont = NULL;
  
    for (i = 0; i < slen; i++) {
      custrinfo[i].flag &= ~(CU_CHINFO_WRAP | CU_CHINFO_SMALLCAPS_CHECK | CU_CHINFO_OVERFLOW);
    }
  
    for (i = 0; i <= slen; i++) {
    makebreak:
      /* Characters in the list */
      info = &custrinfo[i];
      ascii = mem[i];
      if (info->flag & CU_CHINFO_SMALLCAPS) {
        ascii = towupper(ascii);
        if (mem[i] != ascii) {
          info->flag |= CU_CHINFO_SMALLCAPS_CHECK;
        }
      }
  
      vfont = which_vfont(cu, info);
  
      if (vfont == NULL) {
        break;
      }
  
      if (vfont != oldvfont) {
        vfd = vfont_get_data(vfont);
        oldvfont = vfont;
      }
  
      /* VFont Data for VFont couldn't be found */
      if (!vfd) {
        MEM_freeN(chartransdata);
        chartransdata = NULL;
        MEM_freeN(lineinfo);
        goto finally;
      }
  
      if (!ELEM(ascii, '\n', '\0')) {
        BLI_rw_mutex_lock(&vfont_rwlock, THREAD_LOCK_READ);
        che = find_vfont_char(vfd, ascii);
        BLI_rw_mutex_unlock(&vfont_rwlock);
  
        /*
         * The character wasn't in the current curve base so load it
         * But if the font is built-in then do not try loading since
         * whole font is in the memory already
         */
        if (che == NULL && BKE_vfont_is_builtin(vfont) == false) {
          BLI_rw_mutex_lock(&vfont_rwlock, THREAD_LOCK_WRITE);
          /* Check it once again, char might have been already load
           * between previous BLI_rw_mutex_unlock() and this BLI_rw_mutex_lock().
           *
           * Such a check should not be a bottleneck since it wouldn't
           * happen often once all the chars are load.
           */
          if ((che = find_vfont_char(vfd, ascii)) == NULL) {
            che = BLI_vfontchar_from_freetypefont(vfont, ascii);
          }
          BLI_rw_mutex_unlock(&vfont_rwlock);
        }
      }
      else {
        che = NULL;
      }
  
      twidth = char_width(cu, che, info);
  
      /* Calculate positions */
      if ((tb_scale.w != 0.0f) && (ct->dobreak == 0) &&
          (((xof - tb_scale.x) + twidth) > xof_scale + tb_scale.w)) {
        //      CLOG_WARN(&LOG, "linewidth exceeded: %c%c%c...", mem[i], mem[i+1], mem[i+2]);
        for (j = i; j && (mem[j] != '\n') && (chartransdata[j].dobreak == 0); j--) {
          bool dobreak = false;
          if (mem[j] == ' ' || mem[j] == '-') {
            ct -= (i - (j - 1));
            cnr -= (i - (j - 1));
            if (mem[j] == ' ') {
              wsnr--;
            }
            if (mem[j] == '-') {
              wsnr++;
            }
            i = j - 1;
            xof = ct->xof;
            ct[1].dobreak = 1;
            custrinfo[i + 1].flag |= CU_CHINFO_WRAP;
            dobreak = true;
          }
          else if (chartransdata[j].dobreak) {
            //              CLOG_WARN(&LOG, "word too long: %c%c%c...", mem[j], mem[j+1], mem[j+2]);
            ct->dobreak = 1;
            custrinfo[i + 1].flag |= CU_CHINFO_WRAP;
            ct -= 1;
            cnr -= 1;
            i--;
            xof = ct->xof;
            dobreak = true;
          }
          if (dobreak) {
            if (tb_scale.h == 0.0f) {
              /* Note: If underlined text is truncated away, the extra space is also truncated. */
              custrinfo[i + 1].flag |= CU_CHINFO_OVERFLOW;
            }
            goto makebreak;
          }
        }
      }
  
      if (ascii == '\n' || ascii == 0 || ct->dobreak) {
        ct->xof = xof;
        ct->yof = yof;
        ct->linenr = lnr;
        ct->charnr = cnr;
  
        yof -= linedist;
  
        lineinfo[lnr].x_min = (xof - xtrax) - tb_scale.x;
        lineinfo[lnr].x_max = tb_scale.w;
        lineinfo[lnr].char_nr = cnr;
        lineinfo[lnr].wspace_nr = wsnr;
  
        CLAMP_MIN(maxlen, lineinfo[lnr].x_min);
  
        if ((tb_scale.h != 0.0f) && ((-(yof - tb_scale.y)) > (tb_scale.h - linedist) - yof_scale)) {
          if (cu->totbox > (curbox + 1)) {
            maxlen = 0;
            curbox++;
            i_textbox_array[curbox] = i + 1;
  
            textbox_scale(&tb_scale, &cu->tb[curbox], 1.0f / font_size);
  
            yof = MARGIN_Y_MIN;
          }
          else if (last_line == -1) {
            last_line = lnr + 1;
            info->flag |= CU_CHINFO_OVERFLOW;
          }
        }
  
        current_line_length += xof - MARGIN_X_MIN;
        if (ct->dobreak) {
          current_line_length += twidth;
        }
        else {
          longest_line_length = MAX2(current_line_length, longest_line_length);
          current_line_length = 0.0f;
        }
  
        /* XXX, has been unused for years, need to check if this is useful, r4613 r5282 - campbell */
  #if 0
        if (ascii == '\n') {
          xof = xof_scale;
        }
        else {
          xof = MARGIN_X_MIN;
        }
  #else
        xof = MARGIN_X_MIN;
  #endif
        lnr++;
        cnr = 0;
        wsnr = 0;
      }
      else if (ascii == 9) { /* TAB */
        float tabfac;
  
        ct->xof = xof;
        ct->yof = yof;
        ct->linenr = lnr;
        ct->charnr = cnr++;
  
        tabfac = (xof - MARGIN_X_MIN + 0.01f);
        tabfac = 2.0f * ceilf(tabfac / 2.0f);
        xof = MARGIN_X_MIN + tabfac;
      }
      else {
        EditFontSelBox *sb = NULL;
        float wsfac;
  
        ct->xof = xof;
        ct->yof = yof;
        ct->linenr = lnr;
        ct->charnr = cnr++;
  
        if (selboxes && (i >= selstart) && (i <= selend)) {
          sb = &selboxes[i - selstart];
          sb->y = yof * font_size - linedist * font_size * 0.1f;
          sb->h = linedist * font_size;
          sb->w = xof * font_size;
        }
  
        if (ascii == 32) {
          wsfac = cu->wordspace;
          wsnr++;
        }
        else {
          wsfac = 1.0f;
        }
  
        /* Set the width of the character */
        twidth = char_width(cu, che, info);
  
        xof += (twidth * wsfac * (1.0f + (info->kern / 40.0f))) + xtrax;
  
        if (sb) {
          sb->w = (xof * font_size) - sb->w;
        }
      }
      ct++;
    }
    current_line_length += xof + twidth - MARGIN_X_MIN;
    longest_line_length = MAX2(current_line_length, longest_line_length);
  
    cu->lines = 1;
    for (i = 0; i <= slen; i++) {
      ascii = mem[i];
      ct = &chartransdata[i];
      if (ascii == '\n' || ct->dobreak) {
        cu->lines++;
      }
    }
  
    /* linedata is now: width of line */
  
    if (cu->spacemode != CU_ALIGN_X_LEFT) {
      ct = chartransdata;
  
      if (cu->spacemode == CU_ALIGN_X_RIGHT) {
        struct TempLineInfo *li;
  
        for (i = 0, li = lineinfo; i < lnr; i++, li++) {
          li->x_min = (li->x_max - li->x_min) + xof_scale;
        }
  
        for (i = 0; i <= slen; i++) {
          ct->xof += lineinfo[ct->linenr].x_min;
          ct++;
        }
      }
      else if (cu->spacemode == CU_ALIGN_X_MIDDLE) {
        struct TempLineInfo *li;
  
        for (i = 0, li = lineinfo; i < lnr; i++, li++) {
          li->x_min = ((li->x_max - li->x_min) + xof_scale) / 2.0f;
        }
  
        for (i = 0; i <= slen; i++) {
          ct->xof += lineinfo[ct->linenr].x_min;
          ct++;
        }
      }
      else if ((cu->spacemode == CU_ALIGN_X_FLUSH) && use_textbox) {
        struct TempLineInfo *li;
  
        for (i = 0, li = lineinfo; i < lnr; i++, li++) {
          li->x_min = ((li->x_max - li->x_min) + xof_scale);
  
          if (li->char_nr > 1) {
            li->x_min /= (float)(li->char_nr - 1);
          }
        }
        for (i = 0; i <= slen; i++) {
          for (j = i; (!ELEM(mem[j], '\0', '\n')) && (chartransdata[j].dobreak == 0) && (j < slen);
               j++) {
            /* do nothing */
          }
  
          //              if ((mem[j] != '\n') && (mem[j])) {
          ct->xof += ct->charnr * lineinfo[ct->linenr].x_min;
          //              }
          ct++;
        }
      }
      else if ((cu->spacemode == CU_ALIGN_X_JUSTIFY) && use_textbox) {
        float curofs = 0.0f;
        for (i = 0; i <= slen; i++) {
          for (j = i; (mem[j]) && (mem[j] != '\n') && (chartransdata[j].dobreak == 0) && (j < slen);
               j++) {
            /* pass */
          }
  
          if ((mem[j] != '\n') && ((chartransdata[j].dobreak != 0))) {
            if (mem[i] == ' ') {
              struct TempLineInfo *li;
  
              li = &lineinfo[ct->linenr];
              curofs += ((li->x_max - li->x_min) + xof_scale) / (float)li->wspace_nr;
            }
            ct->xof += curofs;
          }
          if (mem[i] == '\n' || chartransdata[i].dobreak) {
            curofs = 0;
          }
          ct++;
        }
      }
    }
  
    /* top-baseline is default, in this case, do nothing */
    if (cu->align_y != CU_ALIGN_Y_TOP_BASELINE) {
      if (tb_scale.h != 0.0f) {
        /* We need to loop all the text-boxes even the "full" ones.
         * This way they all get the same vertical padding. */
        for (int tb_index = 0; tb_index < cu->totbox; tb_index++) {
          struct CharTrans *ct_first, *ct_last;
          const int i_textbox = i_textbox_array[tb_index];
          const int i_textbox_next = i_textbox_array[tb_index + 1];
          const bool is_last_filled_textbox = ELEM(i_textbox_next, 0, slen + 1);
          int lines;
  
          ct_first = chartransdata + i_textbox;
          ct_last = chartransdata + (is_last_filled_textbox ? slen : i_textbox_next - 1);
          lines = ct_last->linenr - ct_first->linenr + 1;
  
          textbox_scale(&tb_scale, &cu->tb[tb_index], 1.0f / font_size);
          /* The initial Y origin of the textbox is hardcoded to 1.0f * text scale. */
          const float textbox_y_origin = 1.0f;
          float yoff = 0.0f;
  
          switch (cu->align_y) {
            case CU_ALIGN_Y_TOP_BASELINE:
              break;
            case CU_ALIGN_Y_TOP:
              yoff = textbox_y_origin - ASCENT(vfd);
              break;
            case CU_ALIGN_Y_CENTER:
              yoff = ((((vfd->em_height + (lines - 1) * linedist) * 0.5f) - ASCENT(vfd)) -
                      (tb_scale.h * 0.5f) + textbox_y_origin);
              break;
            case CU_ALIGN_Y_BOTTOM_BASELINE:
              yoff = textbox_y_origin + ((lines - 1) * linedist) - tb_scale.h;
              break;
            case CU_ALIGN_Y_BOTTOM:
              yoff = textbox_y_origin + ((lines - 1) * linedist) - tb_scale.h + DESCENT(vfd);
              break;
          }
  
          for (ct = ct_first; ct <= ct_last; ct++) {
            ct->yof += yoff;
          }
  
          if (is_last_filled_textbox) {
            break;
          }
        }
      }
      else {
        /* Non text-box case handled separately. */
        float yoff = 0.0f;
  
        switch (cu->align_y) {
          case CU_ALIGN_Y_TOP_BASELINE:
            break;
          case CU_ALIGN_Y_TOP:
            yoff = -ASCENT(vfd);
            break;
          case CU_ALIGN_Y_CENTER:
            yoff = ((vfd->em_height + (lnr - 1) * linedist) * 0.5f) - ASCENT(vfd);
            break;
          case CU_ALIGN_Y_BOTTOM_BASELINE:
            yoff = (lnr - 1) * linedist;
            break;
          case CU_ALIGN_Y_BOTTOM:
            yoff = (lnr - 1) * linedist + DESCENT(vfd);
            break;
        }
  
        ct = chartransdata;
        for (i = 0; i <= slen; i++) {
          ct->yof += yoff;
          ct++;
        }
      }
    }
  
    MEM_freeN(lineinfo);
    MEM_freeN(i_textbox_array);
  
    /* TEXT ON CURVE */
    /* Note: Only OB_CURVE objects could have a path  */
    if (cu->textoncurve && cu->textoncurve->type == OB_CURVE) {
      BLI_assert(cu->textoncurve->runtime.curve_cache != NULL);
      if (cu->textoncurve->runtime.curve_cache != NULL &&
          cu->textoncurve->runtime.curve_cache->path != NULL) {
        float distfac, imat[4][4], imat3[3][3], cmat[3][3];
        float minx, maxx, miny, maxy;
        float timeofs, sizefac;
  
        if (ob != NULL) {
          invert_m4_m4(imat, ob->obmat);
        }
        else {
          unit_m4(imat);
        }
        copy_m3_m4(imat3, imat);
  
        copy_m3_m4(cmat, cu->textoncurve->obmat);
        mul_m3_m3m3(cmat, cmat, imat3);
        sizefac = normalize_v3(cmat[0]) / font_size;
  
        minx = miny = 1.0e20f;
        maxx = maxy = -1.0e20f;
        ct = chartransdata;
        for (i = 0; i <= slen; i++, ct++) {
          if (minx > ct->xof) {
            minx = ct->xof;
          }
          if (maxx < ct->xof) {
            maxx = ct->xof;
          }
          if (miny > ct->yof) {
            miny = ct->yof;
          }
          if (maxy < ct->yof) {
            maxy = ct->yof;
          }
        }
  
        /* we put the x-coordinaat exact at the curve, the y is rotated */
  
        /* length correction */
        distfac = sizefac * cu->textoncurve->runtime.curve_cache->path->totdist / (maxx - minx);
        timeofs = 0.0f;
  
        if (distfac > 1.0f) {
          /* path longer than text: spacemode involves */
          distfac = 1.0f / distfac;
  
          if (cu->spacemode == CU_ALIGN_X_RIGHT) {
            timeofs = 1.0f - distfac;
          }
          else if (cu->spacemode == CU_ALIGN_X_MIDDLE) {
            timeofs = (1.0f - distfac) / 2.0f;
          }
          else if (cu->spacemode == CU_ALIGN_X_FLUSH) {
            distfac = 1.0f;
          }
        }
        else {
          distfac = 1.0;
        }
  
        distfac /= (maxx - minx);
  
        timeofs += distfac * cu->xof; /* not cyclic */
  
        ct = chartransdata;
        for (i = 0; i <= slen; i++, ct++) {
          float ctime, dtime, vec[4], tvec[4], rotvec[3];
          float si, co;
  
          /* rotate around center character */
          info = &custrinfo[i];
          ascii = mem[i];
          if (info->flag & CU_CHINFO_SMALLCAPS_CHECK) {
            ascii = towupper(ascii);
          }
  
          che = find_vfont_char(vfd, ascii);
  
          twidth = char_width(cu, che, info);
  
          dtime = distfac * 0.5f * twidth;
  
          ctime = timeofs + distfac * (ct->xof - minx);
          CLAMP(ctime, 0.0f, 1.0f);
  
          /* calc the right loc AND the right rot separately */
          /* vec, tvec need 4 items */
          where_on_path(cu->textoncurve, ctime, vec, tvec, NULL, NULL, NULL);
          where_on_path(cu->textoncurve, ctime + dtime, tvec, rotvec, NULL, NULL, NULL);
  
          mul_v3_fl(vec, sizefac);
  
          ct->rot = (float)M_PI - atan2f(rotvec[1], rotvec[0]);
  
          si = sinf(ct->rot);
          co = cosf(ct->rot);
  
          yof = ct->yof;
  
          ct->xof = vec[0] + si * yof;
          ct->yof = vec[1] + co * yof;
  
          if (selboxes && (i >= selstart) && (i <= selend)) {
            EditFontSelBox *sb;
            sb = &selboxes[i - selstart];
            sb->rot = -ct->rot;
          }
        }
      }
    }
  
    if (selboxes) {
      ct = chartransdata;
      for (i = 0; i <= selend; i++, ct++) {
        if (i >= selstart) {
          selboxes[i - selstart].x = ct->xof * font_size;
          selboxes[i - selstart].y = ct->yof * font_size;
        }
      }
    }
  
    if (ELEM(mode, FO_CURSUP, FO_CURSDOWN, FO_PAGEUP, FO_PAGEDOWN) &&
        iter_data->status == VFONT_TO_CURVE_INIT) {
      ct = &chartransdata[ef->pos];
  
      if (ELEM(mode, FO_CURSUP, FO_PAGEUP) && ct->linenr == 0) {
        /* pass */
      }
      else if (ELEM(mode, FO_CURSDOWN, FO_PAGEDOWN) && ct->linenr == lnr) {
        /* pass */
      }
      else {
        switch (mode) {
          case FO_CURSUP:
            lnr = ct->linenr - 1;
            break;
          case FO_CURSDOWN:
            lnr = ct->linenr + 1;
            break;
          case FO_PAGEUP:
            lnr = ct->linenr - 10;
            break;
          case FO_PAGEDOWN:
            lnr = ct->linenr + 10;
            break;
        }
        cnr = ct->charnr;
        /* seek for char with lnr en cnr */
        ef->pos = 0;
        ct = chartransdata;
        for (i = 0; i < slen; i++) {
          if (ct->linenr == lnr) {
            if ((ct->charnr == cnr) || ((ct + 1)->charnr == 0)) {
              break;
            }
          }
          else if (ct->linenr > lnr) {
            break;
          }
          ef->pos++;
          ct++;
        }
      }
    }
  
    /* cursor first */
    if (ef) {
      float si, co;
  
      ct = &chartransdata[ef->pos];
      si = sinf(ct->rot);
      co = cosf(ct->rot);
  
      f = ef->textcurs[0];
  
      f[0] = font_size * (-0.1f * co + ct->xof);
      f[1] = font_size * (0.1f * si + ct->yof);
  
      f[2] = font_size * (0.1f * co + ct->xof);
      f[3] = font_size * (-0.1f * si + ct->yof);
  
      f[4] = font_size * (0.1f * co + 0.8f * si + ct->xof);
      f[5] = font_size * (-0.1f * si + 0.8f * co + ct->yof);
  
      f[6] = font_size * (-0.1f * co + 0.8f * si + ct->xof);
      f[7] = font_size * (0.1f * si + 0.8f * co + ct->yof);
    }
  
    if (mode == FO_SELCHANGE) {
      MEM_freeN(chartransdata);
      chartransdata = NULL;
    }
    else if (mode == FO_EDIT) {
      /* make nurbdata */
      BKE_nurbList_free(r_nubase);
  
      ct = chartransdata;
      for (i = 0; i < slen; i++) {
        unsigned int cha = (unsigned int)mem[i];
        info = &(custrinfo[i]);
  
        if ((cu->overflow == CU_OVERFLOW_TRUNCATE) && (ob && ob->mode != OB_MODE_EDIT) &&
            (info->flag & CU_CHINFO_OVERFLOW)) {
          break;
        }
  
        if (info->flag & CU_CHINFO_SMALLCAPS_CHECK) {
          cha = towupper(cha);
        }
  
        /* Only do that check in case we do have an object, otherwise all materials get erased every
         * time that code is called without an object... */
        if (ob != NULL && (info->mat_nr > (ob->totcol))) {
          // CLOG_ERROR(
          //     &LOG, "Illegal material index (%d) in text object, setting to 0", info->mat_nr);
          info->mat_nr = 0;
        }
        /* We do not want to see any character for \n or \r */
        if (cha != '\n') {
          buildchar(cu, r_nubase, cha, info, ct->xof, ct->yof, ct->rot, i, font_size);
        }
  
        if ((info->flag & CU_CHINFO_UNDERLINE) && (cha != '\n')) {
          float ulwidth, uloverlap = 0.0f;
          rctf rect;
  
          if ((i < (slen - 1)) && (mem[i + 1] != '\n') &&
              ((mem[i + 1] != ' ') || (custrinfo[i + 1].flag & CU_CHINFO_UNDERLINE)) &&
              ((custrinfo[i + 1].flag & CU_CHINFO_WRAP) == 0)) {
            uloverlap = xtrax + 0.1f;
          }
          /* Find the character, the characters has to be in the memory already
           * since character checking has been done earlier already. */
          che = find_vfont_char(vfd, cha);
  
          twidth = char_width(cu, che, info);
          ulwidth = (twidth * (1.0f + (info->kern / 40.0f))) + uloverlap;
  
          rect.xmin = ct->xof;
          rect.xmax = rect.xmin + ulwidth;
  
          rect.ymin = ct->yof;
          rect.ymax = rect.ymin - cu->ulheight;
  
          build_underline(
              cu, r_nubase, &rect, cu->ulpos - 0.05f, ct->rot, i, info->mat_nr, font_size);
        }
        ct++;
      }
    }
  
    if (iter_data->status == VFONT_TO_CURVE_SCALE_ONCE) {
      /* That means we were in a final run, just exit. */
      BLI_assert(cu->overflow == CU_OVERFLOW_SCALE);
      iter_data->status = VFONT_TO_CURVE_DONE;
    }
    else if (cu->overflow == CU_OVERFLOW_NONE) {
      /* Do nothing. */
    }
    else if ((tb_scale.h == 0.0f) && (tb_scale.w == 0.0f)) {
      /* Do nothing. */
    }
    else if (cu->overflow == CU_OVERFLOW_SCALE) {
      if ((cu->totbox == 1) && ((tb_scale.w == 0.0f) || (tb_scale.h == 0.0f))) {
        /* These are special cases, simpler to deal with. */
        if (tb_scale.w == 0.0f) {
          /* This is a potential vertical overflow.
           * Since there is no width limit, all the new lines are from line breaks. */
          if ((last_line != -1) && (lnr > last_line)) {
            const float total_text_height = lnr * linedist;
            iter_data->scale_to_fit = tb_scale.h / total_text_height;
            iter_data->status = VFONT_TO_CURVE_SCALE_ONCE;
          }
        }
        else if (tb_scale.h == 0.0f) {
          /* This is a horizontal overflow. */
          if (lnr > 1) {
            /* We make sure longest line before it broke can fit here. */
            float scale_to_fit = tb_scale.w / (longest_line_length);
            scale_to_fit -= FLT_EPSILON;
  
            iter_data->scale_to_fit = scale_to_fit;
            iter_data->status = VFONT_TO_CURVE_SCALE_ONCE;
          }
        }
      }
      else {
        /* This is the really complicated case, the best we can do is to iterate over
         * this function a few times until we get an acceptable result.
         *
         * Keep in mind that there is no single number that will make all fit to the end.
         * In a way, our ultimate goal is to get the highest scale that still leads to the
         * number of extra lines to zero.
         */
        if (iter_data->status == VFONT_TO_CURVE_INIT) {
          bool valid = true;
  
          for (int tb_index = 0; tb_index <= curbox; tb_index++) {
            TextBox *tb = &cu->tb[tb_index];
            if ((tb->w == 0.0f) || (tb->h == 0.0f)) {
              valid = false;
              break;
            }
          }
  
          if (valid && (last_line != -1) && (lnr > last_line)) {
            const float total_text_height = lnr * linedist;
            float scale_to_fit = tb_scale.h / total_text_height;
  
            iter_data->bisect.max = 1.0f;
            iter_data->bisect.min = scale_to_fit;
  
            iter_data->status = VFONT_TO_CURVE_BISECT;
          }
        }
        else {
          BLI_assert(iter_data->status == VFONT_TO_CURVE_BISECT);
          /* Try to get the highest scale that gives us the exactly
           * number of lines we need. */
          bool valid = false;
  
          if ((last_line != -1) && (lnr > last_line)) {
            /* It is overflowing, scale it down. */
            iter_data->bisect.max = iter_data->scale_to_fit;
          }
          else {
            /* It fits inside the textbox, scale it up. */
            iter_data->bisect.min = iter_data->scale_to_fit;
            valid = true;
          }
  
          /* Bisecting to try to find the best fit. */
          iter_data->scale_to_fit = (iter_data->bisect.max + iter_data->bisect.min) * 0.5f;
  
          /* We iterated enough or got a good enough result. */
          if ((!iter_data->iteraction--) || ((iter_data->bisect.max - iter_data->bisect.min) <
                                             (cu->fsize * FONT_TO_CURVE_SCALE_THRESHOLD))) {
            if (valid) {
              iter_data->status = VFONT_TO_CURVE_DONE;
            }
            else {
              iter_data->scale_to_fit = iter_data->bisect.min;
              iter_data->status = VFONT_TO_CURVE_SCALE_ONCE;
            }
          }
        }
      }
    }
  
    /* Scale to fit only works for single text box layouts. */
    if (ELEM(iter_data->status, VFONT_TO_CURVE_SCALE_ONCE, VFONT_TO_CURVE_BISECT)) {
      /* Always cleanup before going to the scale-to-fit repetition. */
      if (r_nubase != NULL) {
        BKE_nurbList_free(r_nubase);
      }
  
      if (chartransdata != NULL) {
        MEM_freeN(chartransdata);
      }
  
      if (ef == NULL) {
        MEM_freeN((void *)mem);
      }
      return true;
    }
    else {
      ok = true;
    finally:
      if (r_text) {
        *r_text = mem;
        *r_text_len = slen;
        *r_text_free = (ef == NULL);
      }
      else {
        if (ef == NULL) {
          MEM_freeN((void *)mem);
        }
      }
  
      if (chartransdata) {
        if (ok && r_chartransdata) {
          *r_chartransdata = chartransdata;
        }
        else {
          MEM_freeN(chartransdata);
        }
      }
  
      /* Store the effective scale, to use for the textbox lines. */
      cu->fsize_realtime = font_size;
    }
    return ok;
  
  #undef MARGIN_X_MIN
  #undef MARGIN_Y_MIN
  }
  
  #undef DESCENT
  #undef ASCENT
  
  bool BKE_vfont_to_curve_ex(Object *ob,
                             Curve *cu,
                             int mode,
                             ListBase *r_nubase,
                             const char32_t **r_text,
                             int *r_text_len,
                             bool *r_text_free,
                             struct CharTrans **r_chartransdata)
  {
    VFontToCurveIter data = {
        .iteraction = cu->totbox * FONT_TO_CURVE_SCALE_ITERATIONS,
        .scale_to_fit = 1.0f,
        .ok = true,
        .status = VFONT_TO_CURVE_INIT,
    };
  
    do {
      data.ok &= vfont_to_curve(
          ob, cu, mode, &data, r_nubase, r_text, r_text_len, r_text_free, r_chartransdata);
    } while (data.ok && ELEM(data.status, VFONT_TO_CURVE_SCALE_ONCE, VFONT_TO_CURVE_BISECT));
  
    return data.ok;
  }
  
  #undef FONT_TO_CURVE_SCALE_ITERATIONS
  #undef FONT_TO_CURVE_SCALE_THRESHOLD
  
  bool BKE_vfont_to_curve_nubase(Object *ob, int mode, ListBase *r_nubase)
  {
    BLI_assert(ob->type == OB_FONT);
  
    return BKE_vfont_to_curve_ex(ob, ob->data, mode, r_nubase, NULL, NULL, NULL, NULL);
  }
  
  /**
   * Warning: expects to have access to evaluated data
   * (i.e. passed object should be evaluated one...).
   */
  bool BKE_vfont_to_curve(Object *ob, int mode)
  {
    Curve *cu = ob->data;
  
    return BKE_vfont_to_curve_ex(ob, ob->data, mode, &cu->nurb, NULL, NULL, NULL, NULL);
  }
  
  /* -------------------------------------------------------------------- */
  /** \name VFont Clipboard
   * \{ */
  
  static struct {
    char32_t *text_buffer;
    CharInfo *info_buffer;
    size_t len_utf32;
    size_t len_utf8;
  } g_vfont_clipboard = {NULL};
  
  void BKE_vfont_clipboard_free(void)
  {
    MEM_SAFE_FREE(g_vfont_clipboard.text_buffer);
    MEM_SAFE_FREE(g_vfont_clipboard.info_buffer);
    g_vfont_clipboard.len_utf32 = 0;
    g_vfont_clipboard.len_utf8 = 0;
  }
  
  void BKE_vfont_clipboard_set(const char32_t *text_buf, const CharInfo *info_buf, const size_t len)
  {
    char32_t *text;
    CharInfo *info;
  
    /* clean previous buffers*/
    BKE_vfont_clipboard_free();
  
    text = MEM_malloc_arrayN((len + 1), sizeof(*text), __func__);
    if (text == NULL) {
      return;
    }
  
    info = MEM_malloc_arrayN(len, sizeof(CharInfo), __func__);
    if (info == NULL) {
      MEM_freeN(text);
      return;
    }
  
    memcpy(text, text_buf, len * sizeof(*text));
    text[len] = '\0';
    memcpy(info, info_buf, len * sizeof(CharInfo));
  
    /* store new buffers */
    g_vfont_clipboard.text_buffer = text;
    g_vfont_clipboard.info_buffer = info;
    g_vfont_clipboard.len_utf8 = BLI_str_utf32_as_utf8_len(text);
    g_vfont_clipboard.len_utf32 = len;
  }
  
  void BKE_vfont_clipboard_get(char32_t **r_text_buf,
                               CharInfo **r_info_buf,
                               size_t *r_len_utf8,
                               size_t *r_len_utf32)
  {
    if (r_text_buf) {
      *r_text_buf = g_vfont_clipboard.text_buffer;
    }
  
    if (r_info_buf) {
      *r_info_buf = g_vfont_clipboard.info_buffer;
    }
  
    if (r_len_utf32) {
      *r_len_utf32 = g_vfont_clipboard.len_utf32;
    }
  
    if (r_len_utf8) {
      *r_len_utf8 = g_vfont_clipboard.len_utf8;
    }
  }
  
  /** \} */
  