text: /*
   * Copyright (c) 2020 Samsung Electronics Co., Ltd. All rights reserved.
  
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
  
   * The above copyright notice and this permission notice shall be included in all
   * copies or substantial portions of the Software.
  
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  #include "tvgSwCommon.h"
  #include "tvgBezier.h"
  
  /************************************************************************/
  /* Internal Class Implementation                                        */
  /************************************************************************/
  
  struct Line
  {
      Point pt1;
      Point pt2;
  };
  
  
  static float _lineLength(const Point& pt1, const Point& pt2)
  {
      /* approximate sqrt(x*x + y*y) using alpha max plus beta min algorithm.
         With alpha = 1, beta = 3/8, giving results with the largest error less
         than 7% compared to the exact value. */
      Point diff = {pt2.x - pt1.x, pt2.y - pt1.y};
      if (diff.x < 0) diff.x = -diff.x;
      if (diff.y < 0) diff.y = -diff.y;
      return (diff.x > diff.y) ? (diff.x + diff.y * 0.375f) : (diff.y + diff.x * 0.375f);
  }
  
  
  static void _lineSplitAt(const Line& cur, float at, Line& left, Line& right)
  {
      auto len = _lineLength(cur.pt1, cur.pt2);
      auto dx = ((cur.pt2.x - cur.pt1.x) / len) * at;
      auto dy = ((cur.pt2.y - cur.pt1.y) / len) * at;
      left.pt1 = cur.pt1;
      left.pt2.x = left.pt1.x + dx;
      left.pt2.y = left.pt1.y + dy;
      right.pt1 = left.pt2;
      right.pt2 = cur.pt2;
  }
  
  
  static void _growOutlineContour(SwOutline& outline, uint32_t n)
  {
      if (outline.reservedCntrsCnt >= outline.cntrsCnt + n) return;
      outline.reservedCntrsCnt = outline.cntrsCnt + n;
      outline.cntrs = static_cast<uint32_t*>(realloc(outline.cntrs, outline.reservedCntrsCnt * sizeof(uint32_t)));
  }
  
  
  static void _growOutlinePoint(SwOutline& outline, uint32_t n)
  {
      if (outline.reservedPtsCnt >= outline.ptsCnt + n) return;
      outline.reservedPtsCnt = outline.ptsCnt + n;
      outline.pts = static_cast<SwPoint*>(realloc(outline.pts, outline.reservedPtsCnt * sizeof(SwPoint)));
      outline.types = static_cast<uint8_t*>(realloc(outline.types, outline.reservedPtsCnt * sizeof(uint8_t)));
  }
  
  
  static void _outlineEnd(SwOutline& outline)
  {
      _growOutlineContour(outline, 1);
      if (outline.ptsCnt > 0) {
          outline.cntrs[outline.cntrsCnt] = outline.ptsCnt - 1;
          ++outline.cntrsCnt;
      }
  }
  
  
  static void _outlineMoveTo(SwOutline& outline, const Point* to, const Matrix* transform)
  {
      _growOutlinePoint(outline, 1);
  
      outline.pts[outline.ptsCnt] = mathTransform(to, transform);
      outline.types[outline.ptsCnt] = SW_CURVE_TYPE_POINT;
  
      if (outline.ptsCnt > 0) {
          _growOutlineContour(outline, 1);
          outline.cntrs[outline.cntrsCnt] = outline.ptsCnt - 1;
          ++outline.cntrsCnt;
      }
  
      ++outline.ptsCnt;
  }
  
  
  static void _outlineLineTo(SwOutline& outline, const Point* to, const Matrix* transform)
  {
      _growOutlinePoint(outline, 1);
  
      outline.pts[outline.ptsCnt] = mathTransform(to, transform);
      outline.types[outline.ptsCnt] = SW_CURVE_TYPE_POINT;
      ++outline.ptsCnt;
  }
  
  
  static void _outlineCubicTo(SwOutline& outline, const Point* ctrl1, const Point* ctrl2, const Point* to, const Matrix* transform)
  {
      _growOutlinePoint(outline, 3);
  
      outline.pts[outline.ptsCnt] = mathTransform(ctrl1, transform);
      outline.types[outline.ptsCnt] = SW_CURVE_TYPE_CUBIC;
      ++outline.ptsCnt;
  
      outline.pts[outline.ptsCnt] = mathTransform(ctrl2, transform);
      outline.types[outline.ptsCnt] = SW_CURVE_TYPE_CUBIC;
      ++outline.ptsCnt;
  
      outline.pts[outline.ptsCnt] = mathTransform(to, transform);
      outline.types[outline.ptsCnt] = SW_CURVE_TYPE_POINT;
      ++outline.ptsCnt;
  }
  
  
  static void _outlineClose(SwOutline& outline)
  {
      uint32_t i = 0;
  
      if (outline.cntrsCnt > 0) {
          i = outline.cntrs[outline.cntrsCnt - 1] + 1;
      } else {
          i = 0;   //First Path
      }
  
      //Make sure there is at least one point in the current path
      if (outline.ptsCnt == i) {
          outline.opened = true;
          return;
      }
  
      //Close the path
      _growOutlinePoint(outline, 1);
  
      outline.pts[outline.ptsCnt] = outline.pts[i];
      outline.types[outline.ptsCnt] = SW_CURVE_TYPE_POINT;
      ++outline.ptsCnt;
  
      outline.opened = false;
  }
  
  
  static void _initBBox(SwBBox& bbox)
  {
      bbox.min.x = bbox.min.y = 0;
      bbox.max.x = bbox.max.y = 0;
  }
  
  
  static bool _updateBBox(SwOutline* outline, SwBBox& bbox)
  {
      if (!outline) return false;
  
      auto pt = outline->pts;
  
      if (outline->ptsCnt <= 0) {
          _initBBox(bbox);
          return false;
      }
  
      auto xMin = pt->x;
      auto xMax = pt->x;
      auto yMin = pt->y;
      auto yMax = pt->y;
  
      ++pt;
  
      for(uint32_t i = 1; i < outline->ptsCnt; ++i, ++pt) {
          if (xMin > pt->x) xMin = pt->x;
          if (xMax < pt->x) xMax = pt->x;
          if (yMin > pt->y) yMin = pt->y;
          if (yMax < pt->y) yMax = pt->y;
      }
      bbox.min.x = xMin >> 6;
      bbox.max.x = (xMax + 63) >> 6;
      bbox.min.y = yMin >> 6;
      bbox.max.y = (yMax + 63) >> 6;
  
      if (xMax - xMin < 1 && yMax - yMin < 1) return false;
  
      return true;
  }
  
  
  static bool _checkValid(const SwOutline* outline, const SwBBox& bbox, const SwSize& clip)
  {
      if (outline->ptsCnt == 0 || outline->cntrsCnt <= 0) return false;
  
      //Check boundary
      if (bbox.min.x >= clip.w || bbox.min.y >= clip.h || bbox.max.x <= 0 || bbox.max.y <= 0) return false;
  
      return true;
  }
  
  
  static void _dashLineTo(SwDashStroke& dash, const Point* to, const Matrix* transform)
  {
      _growOutlinePoint(*dash.outline, dash.outline->ptsCnt >> 1);
      _growOutlineContour(*dash.outline, dash.outline->cntrsCnt >> 1);
  
      Line cur = {dash.ptCur, *to};
      auto len = _lineLength(cur.pt1, cur.pt2);
  
      if (len < dash.curLen) {
          dash.curLen -= len;
          if (!dash.curOpGap) {
              _outlineMoveTo(*dash.outline, &dash.ptCur, transform);
              _outlineLineTo(*dash.outline, to, transform);
          }
      } else {
          while (len > dash.curLen) {
              len -= dash.curLen;
              Line left, right;
              _lineSplitAt(cur, dash.curLen, left, right);;
              dash.curIdx = (dash.curIdx + 1) % dash.cnt;
              if (!dash.curOpGap) {
                  _outlineMoveTo(*dash.outline, &left.pt1, transform);
                  _outlineLineTo(*dash.outline, &left.pt2, transform);
              }
              dash.curLen = dash.pattern[dash.curIdx];
              dash.curOpGap = !dash.curOpGap;
              cur = right;
              dash.ptCur = cur.pt1;
          }
          //leftovers
          dash.curLen -= len;
          if (!dash.curOpGap) {
              _outlineMoveTo(*dash.outline, &cur.pt1, transform);
              _outlineLineTo(*dash.outline, &cur.pt2, transform);
          }
          if (dash.curLen < 1 && TO_SWCOORD(len) > 1) {
              //move to next dash
              dash.curIdx = (dash.curIdx + 1) % dash.cnt;
              dash.curLen = dash.pattern[dash.curIdx];
              dash.curOpGap = !dash.curOpGap;
          }
      }
      dash.ptCur = *to;
  }
  
  
  static void _dashCubicTo(SwDashStroke& dash, const Point* ctrl1, const Point* ctrl2, const Point* to, const Matrix* transform)
  {
      _growOutlinePoint(*dash.outline, dash.outline->ptsCnt >> 1);
      _growOutlineContour(*dash.outline, dash.outline->cntrsCnt >> 1);
  
      Bezier cur = {dash.ptCur, *ctrl1, *ctrl2, *to};
      auto len = bezLength(cur);
  
      if (len < dash.curLen) {
          dash.curLen -= len;
          if (!dash.curOpGap) {
              _outlineMoveTo(*dash.outline, &dash.ptCur, transform);
              _outlineCubicTo(*dash.outline, ctrl1, ctrl2, to, transform);
          }
      } else {
          while (len > dash.curLen) {
              Bezier left, right;
              len -= dash.curLen;
              bezSplitAt(cur, dash.curLen, left, right);
              dash.curIdx = (dash.curIdx + 1) % dash.cnt;
              if (!dash.curOpGap) {
                  _outlineMoveTo(*dash.outline, &left.start, transform);
                  _outlineCubicTo(*dash.outline, &left.ctrl1, &left.ctrl2, &left.end, transform);
              }
              dash.curLen = dash.pattern[dash.curIdx];
              dash.curOpGap = !dash.curOpGap;
              cur = right;
              dash.ptCur = right.start;
          }
          //leftovers
          dash.curLen -= len;
          if (!dash.curOpGap) {
              _outlineMoveTo(*dash.outline, &cur.start, transform);
              _outlineCubicTo(*dash.outline, &cur.ctrl1, &cur.ctrl2, &cur.end, transform);
          }
          if (dash.curLen < 1 && TO_SWCOORD(len) > 1) {
              //move to next dash
              dash.curIdx = (dash.curIdx + 1) % dash.cnt;
              dash.curLen = dash.pattern[dash.curIdx];
              dash.curOpGap = !dash.curOpGap;
          }
      }
      dash.ptCur = *to;
  }
  
  
  SwOutline* _genDashOutline(const Shape* sdata, const Matrix* transform)
  {
      const PathCommand* cmds = nullptr;
      auto cmdCnt = sdata->pathCommands(&cmds);
  
      const Point* pts = nullptr;
      auto ptsCnt = sdata->pathCoords(&pts);
  
      //No actual shape data
      if (cmdCnt == 0 || ptsCnt == 0) return nullptr;
  
      SwDashStroke dash;
      dash.curIdx = 0;
      dash.curLen = 0;
      dash.ptStart = {0, 0};
      dash.ptCur = {0, 0};
      dash.curOpGap = false;
  
      const float* pattern;
      dash.cnt = sdata->strokeDash(&pattern);
      if (dash.cnt == 0) return nullptr;
  
      //OPTMIZE ME: Use mempool???
      dash.pattern = const_cast<float*>(pattern);
      dash.outline = static_cast<SwOutline*>(calloc(1, sizeof(SwOutline)));
      dash.outline->opened = true;
  
      //smart reservation
      auto outlinePtsCnt = 0;
      auto outlineCntrsCnt = 0;
  
      for (uint32_t i = 0; i < cmdCnt; ++i) {
          switch(*(cmds + i)) {
              case PathCommand::Close: {
                  ++outlinePtsCnt;
                  break;
              }
              case PathCommand::MoveTo: {
                  ++outlineCntrsCnt;
                  ++outlinePtsCnt;
                  break;
              }
              case PathCommand::LineTo: {
                  ++outlinePtsCnt;
                  break;
              }
              case PathCommand::CubicTo: {
                  outlinePtsCnt += 3;
                  break;
              }
          }
      }
  
      ++outlinePtsCnt;    //for close
      ++outlineCntrsCnt;  //for end
  
      //Reserve Approximitely 20x...
      _growOutlinePoint(*dash.outline, outlinePtsCnt * 20);
      _growOutlineContour(*dash.outline, outlineCntrsCnt * 20);
  
      while (cmdCnt-- > 0) {
          switch(*cmds) {
              case PathCommand::Close: {
                  _dashLineTo(dash, &dash.ptStart, transform);
                  break;
              }
              case PathCommand::MoveTo: {
                  //reset the dash
                  dash.curIdx = 0;
                  dash.curLen = *dash.pattern;
                  dash.curOpGap = false;
                  dash.ptStart = dash.ptCur = *pts;
                  ++pts;
                  break;
              }
              case PathCommand::LineTo: {
                  _dashLineTo(dash, pts, transform);
                  ++pts;
                  break;
              }
              case PathCommand::CubicTo: {
                  _dashCubicTo(dash, pts, pts + 1, pts + 2, transform);
                  pts += 3;
                  break;
              }
          }
          ++cmds;
      }
  
      _outlineEnd(*dash.outline);
  
      return dash.outline;
  }
  
  
  bool _fastTrack(const SwOutline* outline)
  {
      //Fast Track: Othogonal rectangle?
      if (outline->ptsCnt != 5) return false;
  
      auto pt1 = outline->pts + 0;
      auto pt2 = outline->pts + 1;
      auto pt3 = outline->pts + 2;
      auto pt4 = outline->pts + 3;
  
      auto a = SwPoint{pt1->x, pt3->y};
      auto b = SwPoint{pt3->x, pt1->y};
  
      if ((*pt2 == a && *pt4 == b) || (*pt2 == b && *pt4 == a)) return true;
  
      return false;
  }
  
  
  /************************************************************************/
  /* External Class Implementation                                        */
  /************************************************************************/
  
  bool shapePrepare(SwShape* shape, const Shape* sdata, unsigned tid, const SwSize& clip, const Matrix* transform, SwBBox& bbox)
  {
      if (!shapeGenOutline(shape, sdata, tid, transform)) return false;
  
      if (!_updateBBox(shape->outline, shape->bbox)) return false;
  
      if (!_checkValid(shape->outline, shape->bbox, clip)) return false;
  
      bbox = shape->bbox;
  
      return true;
  }
  
  
  bool shapePrepared(SwShape* shape)
  {
      return shape->rle ? true : false;
  }
  
  
  bool shapeGenRle(SwShape* shape, TVG_UNUSED const Shape* sdata, const SwSize& clip, bool antiAlias, bool hasComposite)
  {
      //FIXME: Should we draw it?
      //Case: Stroke Line
      //if (shape.outline->opened) return true;
  
      //Case A: Fast Track Rectangle Drawing
      if (!hasComposite && (shape->rect = _fastTrack(shape->outline))) return true;
      //Case B: Normale Shape RLE Drawing
      if ((shape->rle = rleRender(shape->rle, shape->outline, shape->bbox, clip, antiAlias))) return true;
  
      return false;
  }
  
  
  void shapeDelOutline(SwShape* shape, uint32_t tid)
  {
      mpoolRetOutline(tid);
      shape->outline = nullptr;
  }
  
  
  void shapeReset(SwShape* shape)
  {
      rleReset(shape->rle);
      rleReset(shape->strokeRle);
      shape->rect = false;
      _initBBox(shape->bbox);
  }
  
  
  bool shapeGenOutline(SwShape* shape, const Shape* sdata, unsigned tid, const Matrix* transform)
  {
      const PathCommand* cmds = nullptr;
      auto cmdCnt = sdata->pathCommands(&cmds);
  
      const Point* pts = nullptr;
      auto ptsCnt = sdata->pathCoords(&pts);
  
      //No actual shape data
      if (cmdCnt == 0 || ptsCnt == 0) return false;
  
      //smart reservation
      auto outlinePtsCnt = 0;
      auto outlineCntrsCnt = 0;
  
      for (uint32_t i = 0; i < cmdCnt; ++i) {
          switch(*(cmds + i)) {
              case PathCommand::Close: {
                  ++outlinePtsCnt;
                  break;
              }
              case PathCommand::MoveTo: {
                  ++outlineCntrsCnt;
                  ++outlinePtsCnt;
                  break;
              }
              case PathCommand::LineTo: {
                  ++outlinePtsCnt;
                  break;
              }
              case PathCommand::CubicTo: {
                  outlinePtsCnt += 3;
                  break;
              }
          }
      }
  
      ++outlinePtsCnt;    //for close
      ++outlineCntrsCnt;  //for end
  
      shape->outline = mpoolReqOutline(tid);
      auto outline = shape->outline;
      outline->opened = true;
  
      _growOutlinePoint(*outline, outlinePtsCnt);
      _growOutlineContour(*outline, outlineCntrsCnt);
  
      auto closed = false;
  
      //Generate Outlines
      while (cmdCnt-- > 0) {
          switch(*cmds) {
              case PathCommand::Close: {
                  _outlineClose(*outline);
                  closed = true;
                  break;
              }
              case PathCommand::MoveTo: {
                  _outlineMoveTo(*outline, pts, transform);
                  ++pts;
                  break;
              }
              case PathCommand::LineTo: {
                  _outlineLineTo(*outline, pts, transform);
                  ++pts;
                  break;
              }
              case PathCommand::CubicTo: {
                  _outlineCubicTo(*outline, pts, pts + 1, pts + 2, transform);
                  pts += 3;
                  break;
              }
          }
          ++cmds;
      }
  
      _outlineEnd(*outline);
  
      if (closed) outline->opened = false;
  
      outline->fillRule = sdata->fillRule();
      shape->outline = outline;
  
      return true;
  }
  
  
  void shapeFree(SwShape* shape)
  {
      rleFree(shape->rle);
      shapeDelFill(shape);
  
      if (shape->stroke) {
          rleFree(shape->strokeRle);
          strokeFree(shape->stroke);
      }
  }
  
  
  void shapeDelStroke(SwShape* shape)
  {
      if (!shape->stroke) return;
      rleFree(shape->strokeRle);
      shape->strokeRle = nullptr;
      strokeFree(shape->stroke);
      shape->stroke = nullptr;
  }
  
  
  void shapeResetStroke(SwShape* shape, const Shape* sdata, const Matrix* transform)
  {
      if (!shape->stroke) shape->stroke = static_cast<SwStroke*>(calloc(1, sizeof(SwStroke)));
      auto stroke = shape->stroke;
      if (!stroke) return;
  
      strokeReset(stroke, sdata, transform);
      rleReset(shape->strokeRle);
  }
  
  
  bool shapeGenStrokeRle(SwShape* shape, const Shape* sdata, unsigned tid, const Matrix* transform, const SwSize& clip, SwBBox& bbox)
  {
      SwOutline* shapeOutline = nullptr;
      SwOutline* strokeOutline = nullptr;
      bool freeOutline = false;
      bool ret = true;
  
      //Dash Style Stroke
      if (sdata->strokeDash(nullptr) > 0) {
          shapeOutline = _genDashOutline(sdata, transform);
          if (!shapeOutline) return false;
          freeOutline = true;
      //Normal Style stroke
      } else {
          if (!shape->outline) {
              if (!shapeGenOutline(shape, sdata, tid, transform)) return false;
          }
          shapeOutline = shape->outline;
      }
  
      if (!strokeParseOutline(shape->stroke, *shapeOutline)) {
          ret = false;
          goto fail;
      }
  
      strokeOutline = strokeExportOutline(shape->stroke, tid);
      if (!strokeOutline) {
          ret = false;
          goto fail;
      }
  
      _updateBBox(strokeOutline, bbox);
  
      if (!_checkValid(strokeOutline, bbox, clip)) {
          ret = false;
          goto fail;
      }
  
      shape->strokeRle = rleRender(shape->strokeRle, strokeOutline, bbox, clip, true);
  
  fail:
      if (freeOutline) {
          if (shapeOutline->cntrs) free(shapeOutline->cntrs);
          if (shapeOutline->pts) free(shapeOutline->pts);
          if (shapeOutline->types) free(shapeOutline->types);
          free(shapeOutline);
      }
      mpoolRetStrokeOutline(tid);
  
      return ret;
  }
  
  
  bool shapeGenFillColors(SwShape* shape, const Fill* fill, const Matrix* transform, SwSurface* surface, uint32_t opacity, bool ctable)
  {
      return fillGenColorTable(shape->fill, fill, transform, surface, opacity, ctable);
  }
  
  
  void shapeResetFill(SwShape* shape)
  {
      if (!shape->fill) {
          shape->fill = static_cast<SwFill*>(calloc(1, sizeof(SwFill)));
          if (!shape->fill) return;
      }
      fillReset(shape->fill);
  }
  
  
  void shapeDelFill(SwShape* shape)
  {
      if (!shape->fill) return;
      fillFree(shape->fill);
      shape->fill = nullptr;
  }
  