splash.cc

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  }
  oldState = state;
  state = state->next;
  delete oldState;
  return splashOk;
}

//------------------------------------------------------------------------
// drawing operations
//------------------------------------------------------------------------

void Splash::clear(SplashColorPtr color, Guchar alpha) {
  SplashColorPtr row, p;
  Guchar mono;
  int x, y;

  switch (bitmap->mode) {
  case splashModeMono1:
    mono = (color[0] & 0x80) ? 0xff : 0x00;
    if (bitmap->rowSize < 0) {
      memset(bitmap->data + bitmap->rowSize * (bitmap->height - 1),
	     mono, -bitmap->rowSize * bitmap->height);
    } else {
      memset(bitmap->data, mono, bitmap->rowSize * bitmap->height);
    }
    break;
  case splashModeMono8:
    if (bitmap->rowSize < 0) {
      memset(bitmap->data + bitmap->rowSize * (bitmap->height - 1),
	     color[0], -bitmap->rowSize * bitmap->height);
    } else {
      memset(bitmap->data, color[0], bitmap->rowSize * bitmap->height);
    }
    break;
  case splashModeRGB8:
    if (color[0] == color[1] && color[1] == color[2]) {
      if (bitmap->rowSize < 0) {
	memset(bitmap->data + bitmap->rowSize * (bitmap->height - 1),
	       color[0], -bitmap->rowSize * bitmap->height);
      } else {
	memset(bitmap->data, color[0], bitmap->rowSize * bitmap->height);
      }
    } else {
      row = bitmap->data;
      for (y = 0; y < bitmap->height; ++y) {
	p = row;
	for (x = 0; x < bitmap->width; ++x) {
	  *p++ = color[2];
	  *p++ = color[1];
	  *p++ = color[0];
	}
	row += bitmap->rowSize;
      }
    }
    break;
  case splashModeBGR8:
    if (color[0] == color[1] && color[1] == color[2]) {
      if (bitmap->rowSize < 0) {
	memset(bitmap->data + bitmap->rowSize * (bitmap->height - 1),
	       color[0], -bitmap->rowSize * bitmap->height);
      } else {
	memset(bitmap->data, color[0], bitmap->rowSize * bitmap->height);
      }
    } else {
      row = bitmap->data;
      for (y = 0; y < bitmap->height; ++y) {
	p = row;
	for (x = 0; x < bitmap->width; ++x) {
	  *p++ = color[0];
	  *p++ = color[1];
	  *p++ = color[2];
	}
	row += bitmap->rowSize;
      }
    }
    break;
#if SPLASH_CMYK
  case splashModeCMYK8:
    if (color[0] == color[1] && color[1] == color[2] && color[2] == color[3]) {
      if (bitmap->rowSize < 0) {
	memset(bitmap->data + bitmap->rowSize * (bitmap->height - 1),
	       color[0], -bitmap->rowSize * bitmap->height);
      } else {
	memset(bitmap->data, color[0], bitmap->rowSize * bitmap->height);
      }
    } else {
      row = bitmap->data;
      for (y = 0; y < bitmap->height; ++y) {
	p = row;
	for (x = 0; x < bitmap->width; ++x) {
	  *p++ = color[0];
	  *p++ = color[1];
	  *p++ = color[2];
	  *p++ = color[3];
	}
	row += bitmap->rowSize;
      }
    }
    break;
#endif
  }

  if (bitmap->alpha) {
    memset(bitmap->alpha, alpha, bitmap->width * bitmap->height);
  }

  updateModX(0);
  updateModY(0);
  updateModX(bitmap->width - 1);
  updateModY(bitmap->height - 1);
}

SplashError Splash::stroke(SplashPath *path) {
  SplashPath *path2, *dPath;

  if (debugMode) {
    printf("stroke [dash:%d] [width:%.2f]:\n",
	   state->lineDashLength, (double)state->lineWidth);
    dumpPath(path);
  }
  opClipRes = splashClipAllOutside;
  if (path->length == 0) {
    return splashErrEmptyPath;
  }
  path2 = flattenPath(path, state->matrix, state->flatness);
  if (state->lineDashLength > 0) {
    dPath = makeDashedPath(path2);
    delete path2;
    path2 = dPath;
  }
  if (state->lineWidth == 0) {
    strokeNarrow(path2);
  } else {
    strokeWide(path2);
  }
  delete path2;
  return splashOk;
}

void Splash::strokeNarrow(SplashPath *path) {
  SplashPipe pipe;
  SplashXPath *xPath;
  SplashXPathSeg *seg;
  int x0, x1, x2, x3, y0, y1, x, y, t;
  SplashCoord dx, dy, dxdy;
  SplashClipResult clipRes;
  int nClipRes[3];
  int i;

  nClipRes[0] = nClipRes[1] = nClipRes[2] = 0;

  xPath = new SplashXPath(path, state->matrix, state->flatness, gFalse);

  pipeInit(&pipe, 0, 0, state->strokePattern, NULL, state->strokeAlpha,
	   gFalse, gFalse);

  for (i = 0, seg = xPath->segs; i < xPath->length; ++i, ++seg) {

    x0 = splashFloor(seg->x0);
    x1 = splashFloor(seg->x1);
    y0 = splashFloor(seg->y0);
    y1 = splashFloor(seg->y1);

    // horizontal segment
    if (y0 == y1) {
      if (x0 > x1) {
	t = x0; x0 = x1; x1 = t;
      }
      if ((clipRes = state->clip->testSpan(x0, x1, y0))
	  != splashClipAllOutside) {
	drawSpan(&pipe, x0, x1, y0, clipRes == splashClipAllInside);
      }

    // segment with |dx| > |dy|
    } else if (splashAbs(seg->dxdy) > 1) {
      dx = seg->x1 - seg->x0;
      dy = seg->y1 - seg->y0;
      dxdy = seg->dxdy;
      if (y0 > y1) {
	t = y0; y0 = y1; y1 = t;
	t = x0; x0 = x1; x1 = t;
	dx = -dx;
	dy = -dy;
      }
      if ((clipRes = state->clip->testRect(x0 <= x1 ? x0 : x1, y0,
					   x0 <= x1 ? x1 : x0, y1))
	  != splashClipAllOutside) {
	if (dx > 0) {
	  x2 = x0;
	  x3 = splashFloor(seg->x0 + ((SplashCoord)y0 + 1 - seg->y0) * dxdy);
	  drawSpan(&pipe, x2, (x2 <= x3 - 1) ? x3 - 1 : x2, y0,
		   clipRes == splashClipAllInside);
	  x2 = x3;
	  for (y = y0 + 1; y <= y1 - 1; ++y) {
	    x3 = splashFloor(seg->x0 + ((SplashCoord)y + 1 - seg->y0) * dxdy);
	    drawSpan(&pipe, x2, x3 - 1, y, clipRes == splashClipAllInside);
	    x2 = x3;
	  }
	  drawSpan(&pipe, x2, x2 <= x1 ? x1 : x2, y1,
		   clipRes == splashClipAllInside);
	} else {
	  x2 = x0;
	  x3 = splashFloor(seg->x0 + ((SplashCoord)y0 + 1 - seg->y0) * dxdy);
	  drawSpan(&pipe, (x3 + 1 <= x2) ? x3 + 1 : x2, x2, y0,
		   clipRes == splashClipAllInside);
	  x2 = x3;
	  for (y = y0 + 1; y <= y1 - 1; ++y) {
	    x3 = splashFloor(seg->x0 + ((SplashCoord)y + 1 - seg->y0) * dxdy);
	    drawSpan(&pipe, x3 + 1, x2, y, clipRes == splashClipAllInside);
	    x2 = x3;
	  }
	  drawSpan(&pipe, x1, (x1 <= x2) ? x2 : x1, y1,
		   clipRes == splashClipAllInside);
	}
      }

    // segment with |dy| > |dx|
    } else {
      dxdy = seg->dxdy;
      if (y0 > y1) {
	t = x0; x0 = x1; x1 = t;
	t = y0; y0 = y1; y1 = t;
      }
      if ((clipRes = state->clip->testRect(x0 <= x1 ? x0 : x1, y0,
					   x0 <= x1 ? x1 : x0, y1))
	  != splashClipAllOutside) {
	drawPixel(&pipe, x0, y0, clipRes == splashClipAllInside);
	for (y = y0 + 1; y <= y1 - 1; ++y) {
	  x = splashFloor(seg->x0 + ((SplashCoord)y - seg->y0) * dxdy);
	  drawPixel(&pipe, x, y, clipRes == splashClipAllInside);
	}
	drawPixel(&pipe, x1, y1, clipRes == splashClipAllInside);
      }
    }
    ++nClipRes[clipRes];
  }
  if (nClipRes[splashClipPartial] ||
      (nClipRes[splashClipAllInside] && nClipRes[splashClipAllOutside])) {
    opClipRes = splashClipPartial;
  } else if (nClipRes[splashClipAllInside]) {
    opClipRes = splashClipAllInside;
  } else {
    opClipRes = splashClipAllOutside;
  }

  delete xPath;
}

void Splash::strokeWide(SplashPath *path) {
  SplashPath *path2;

  path2 = makeStrokePath(path, gFalse);
  fillWithPattern(path2, gFalse, state->strokePattern, state->strokeAlpha);
  delete path2;
}

SplashPath *Splash::flattenPath(SplashPath *path, SplashCoord *matrix,
				SplashCoord flatness) {
  SplashPath *fPath;
  SplashCoord flatness2;
  Guchar flag;
  int i;

  fPath = new SplashPath();
  flatness2 = flatness * flatness;
  i = 0;
  while (i < path->length) {
    flag = path->flags[i];
    if (flag & splashPathFirst) {
      fPath->moveTo(path->pts[i].x, path->pts[i].y);
      ++i;
    } else {
      if (flag & splashPathCurve) {
	flattenCurve(path->pts[i-1].x, path->pts[i-1].y,
		     path->pts[i  ].x, path->pts[i  ].y,
		     path->pts[i+1].x, path->pts[i+1].y,
		     path->pts[i+2].x, path->pts[i+2].y,
		     matrix, flatness2, fPath);
	i += 3;
      } else {
	fPath->lineTo(path->pts[i].x, path->pts[i].y);
	++i;
      }
      if (path->flags[i-1] & splashPathClosed) {
	fPath->close();
      }
    }
  }
  return fPath;
}

void Splash::flattenCurve(SplashCoord x0, SplashCoord y0,
			  SplashCoord x1, SplashCoord y1,
			  SplashCoord x2, SplashCoord y2,
			  SplashCoord x3, SplashCoord y3,
			  SplashCoord *matrix, SplashCoord flatness2,
			  SplashPath *fPath) {
  SplashCoord cx[splashMaxCurveSplits + 1][3];
  SplashCoord cy[splashMaxCurveSplits + 1][3];
  int cNext[splashMaxCurveSplits + 1];
  SplashCoord xl0, xl1, xl2, xr0, xr1, xr2, xr3, xx1, xx2, xh;
  SplashCoord yl0, yl1, yl2, yr0, yr1, yr2, yr3, yy1, yy2, yh;
  SplashCoord dx, dy, mx, my, tx, ty, d1, d2;
  int p1, p2, p3;

  // initial segment
  p1 = 0;
  p2 = splashMaxCurveSplits;
  cx[p1][0] = x0;  cy[p1][0] = y0;
  cx[p1][1] = x1;  cy[p1][1] = y1;
  cx[p1][2] = x2;  cy[p1][2] = y2;
  cx[p2][0] = x3;  cy[p2][0] = y3;
  cNext[p1] = p2;

  while (p1 < splashMaxCurveSplits) {

    // get the next segment
    xl0 = cx[p1][0];  yl0 = cy[p1][0];
    xx1 = cx[p1][1];  yy1 = cy[p1][1];
    xx2 = cx[p1][2];  yy2 = cy[p1][2];
    p2 = cNext[p1];
    xr3 = cx[p2][0];  yr3 = cy[p2][0];

    // compute the distances (in device space) from the control points
    // to the midpoint of the straight line (this is a bit of a hack,
    // but it's much faster than computing the actual distances to the
    // line)
    transform(matrix, (xl0 + xr3) * 0.5, (yl0 + yr3) * 0.5, &mx, &my);
    transform(matrix, xx1, yy1, &tx, &ty);
    dx = tx - mx;
    dy = ty - my;
    d1 = dx*dx + dy*dy;
    transform(matrix, xx2, yy2, &tx, &ty);
    dx = tx - mx;
    dy = ty - my;
    d2 = dx*dx + dy*dy;

    // if the curve is flat enough, or no more subdivisions are
    // allowed, add the straight line segment
    if (p2 - p1 == 1 || (d1 <= flatness2 && d2 <= flatness2)) {
      fPath->lineTo(xr3, yr3);
      p1 = p2;

    // otherwise, subdivide the curve
    } else {
      xl1 = (xl0 + xx1) * 0.5;
      yl1 = (yl0 + yy1) * 0.5;
      xh = (xx1 + xx2) * 0.5;
      yh = (yy1 + yy2) * 0.5;
      xl2 = (xl1 + xh) * 0.5;
      yl2 = (yl1 + yh) * 0.5;
      xr2 = (xx2 + xr3) * 0.5;
      yr2 = (yy2 + yr3) * 0.5;
      xr1 = (xh + xr2) * 0.5;
      yr1 = (yh + yr2) * 0.5;
      xr0 = (xl2 + xr1) * 0.5;
      yr0 = (yl2 + yr1) * 0.5;
      // add the new subdivision points
      p3 = (p1 + p2) / 2;
      cx[p1][1] = xl1;  cy[p1][1] = yl1;
      cx[p1][2] = xl2;  cy[p1][2] = yl2;
      cNext[p1] = p3;
      cx[p3][0] = xr0;  cy[p3][0] = yr0;
      cx[p3][1] = xr1;  cy[p3][1] = yr1;
      cx[p3][2] = xr2;  cy[p3][2] = yr2;
      cNext[p3] = p2;
    }
  }
}

SplashPath *Splash::makeDashedPath(SplashPath *path) {
  SplashPath *dPath;
  SplashCoord lineDashTotal;
  SplashCoord lineDashStartPhase, lineDashDist, segLen;
  SplashCoord x0, y0, x1, y1, xa, ya;
  GBool lineDashStartOn, lineDashOn, newPath;
  int lineDashStartIdx, lineDashIdx;
  int i, j, k;

  lineDashTotal = 0;
  for (i = 0; i < state->lineDashLength; ++i) {
    lineDashTotal += state->lineDash[i];
  }
  lineDashStartPhase = state->lineDashPhase;
  i = splashFloor(lineDashStartPhase / lineDashTotal);
  lineDashStartPhase -= (SplashCoord)i * lineDashTotal;
  lineDashStartOn = gTrue;
  lineDashStartIdx = 0;
  while (lineDashStartPhase >= state->lineDash[lineDashStartIdx]) {
    lineDashStartOn = !lineDashStartOn;
    lineDashStartPhase -= state->lineDash[lineDashStartIdx];
    ++lineDashStartIdx;
  }

  dPath = new SplashPath();

  // process each subpath
  i = 0;
  while (i < path->length) {

    // find the end of the subpath
    for (j = i;
	 j < path->length - 1 && !(path->flags[j] & splashPathLast);
	 ++j) ;

    // initialize the dash parameters
    lineDashOn = lineDashStartOn;
    lineDashIdx = lineDashStartIdx;
    lineDashDist = state->lineDash[lineDashIdx] - lineDashStartPhase;

    // process each segment of the subpath
    newPath = gTrue;
    for (k = i; k < j; ++k) {

      // grab the segment
      x0 = path->pts[k].x;
      y0 = path->pts[k].y;
      x1 = path->pts[k+1].x;
      y1 = path->pts[k+1].y;
      segLen = splashDist(x0, y0, x1, y1);

      // process the segment
      while (segLen > 0) {

	if (lineDashDist >= segLen) {
	  if (lineDashOn) {
	    if (newPath) {
	      dPath->moveTo(x0, y0);
	      newPath = gFalse;
	    }
	    dPath->lineTo(x1, y1);
	  }
	  lineDashDist -= segLen;
	  segLen = 0;

	} else {
	  xa = x0 + (lineDashDist / segLen) * (x1 - x0);
	  ya = y0 + (lineDashDist / segLen) * (y1 - y0);
	  if (lineDashOn) {
	    if (newPath) {
	      dPath->moveTo(x0, y0);
	      newPath = gFalse;
	    }
	    dPath->lineTo(xa, ya);
	  }
	  x0 = xa;
	  y0 = ya;
	  segLen -= lineDashDist;
	  lineDashDist = 0;
	}

	// get the next entry in the dash array
	if (lineDashDist <= 0) {
	  lineDashOn = !lineDashOn;
	  if (++lineDashIdx == state->lineDashLength) {
	    lineDashIdx = 0;
	  }
	  lineDashDist = state->lineDash[lineDashIdx];
	  newPath = gTrue;
	}
      }
    }
    i = j + 1;
  }

  return dPath;
}

SplashError Splash::fill(SplashPath *path, GBool eo) {
  if (debugMode) {
    printf("fill [eo:%d]:\n", eo);
    dumpPath(path);
  }
  return fillWithPattern(path, eo, state->fillPattern, state->fillAlpha);
}

SplashError Splash::fillWithPattern(SplashPath *path, GBool eo,
				    SplashPattern *pattern,
				    SplashCoord alpha) {
  SplashPipe pipe;
  SplashXPath *xPath;
  SplashXPathScanner *scanner;
  int xMinI, yMinI, xMaxI, yMaxI, x0, x1, y;
  SplashClipResult clipRes, clipRes2;

  if (path->length == 0) {
    return splashErrEmptyPath;
  }
  xPath = new SplashXPath(path, state->matrix, state->flatness, gTrue);
  if (vectorAntialias) {
    xPath->aaScale();
  }
  xPath->sort();
  scanner = new SplashXPathScanner(xPath, eo);

  // get the min and max x and y values
  if (vectorAntialias) {
    scanner->getBBoxAA(&xMinI, &yMinI, &xMaxI, &yMaxI);
  } else {
    scanner->getBBox(&xMinI, &yMinI, &xMaxI, &yMaxI);
  }

  // check clipping
  if ((clipRes = state->clip->testRect(xMinI, yMinI, xMaxI, yMaxI))
      != splashClipAllOutside) {