splash.cc

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      }

    // 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(x0, y0, state->strokePattern, state->strokeAlpha,
		  clipRes == splashClipAllInside);
	for (y = y0 + 1; y <= y1 - 1; ++y) {
	  x = splashFloor(seg->x0 + ((SplashCoord)y - seg->y0) * dxdy);
	  drawPixel(x, y, state->strokePattern, state->strokeAlpha,
		    clipRes == splashClipAllInside);
	}
	drawPixel(x1, y1, state->strokePattern, state->strokeAlpha,
		  clipRes == splashClipAllInside);
      }
    }
    ++nClipRes[clipRes];
  }
  if (nClipRes[splashClipPartial] ||
      (nClipRes[splashClipAllInside] && nClipRes[splashClipAllOutside])) {
    opClipRes = splashClipPartial;
  } else if (nClipRes[splashClipAllInside]) {
    opClipRes = splashClipAllInside;
  } else {
    opClipRes = splashClipAllOutside;
  }
}

void Splash::strokeWide(SplashXPath *xPath) {
  SplashXPathSeg *seg, *seg2;
  SplashPath *widePath;
  SplashCoord d, dx, dy, wdx, wdy, dxPrev, dyPrev, wdxPrev, wdyPrev;
  SplashCoord dotprod, miter;
  int i, j;

  dx = dy = wdx = wdy = 0; // make gcc happy
  dxPrev = dyPrev = wdxPrev = wdyPrev = 0; // make gcc happy

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

    // save the deltas for the previous segment; if this is the first
    // segment on a subpath, compute the deltas for the last segment
    // on the subpath (which may be used to draw a line join)
    if (seg->flags & splashXPathFirst) {
      for (j = i + 1, seg2 = &xPath->segs[j]; j < xPath->length; ++j, ++seg2) {
	if (seg2->flags & splashXPathLast) {
	  d = splashDist(seg2->x0, seg2->y0, seg2->x1, seg2->y1);
	  if (d == 0) {
	    //~ not clear what the behavior should be for joins with d==0
	    dxPrev = 0;
	    dyPrev = 1;
	  } else {
	    d = (SplashCoord)1 / d;
	    dxPrev = d * (seg2->x1 - seg2->x0);
	    dyPrev = d * (seg2->y1 - seg2->y0);
	  }
	  wdxPrev = (SplashCoord)0.5 * state->lineWidth * dxPrev;
	  wdyPrev = (SplashCoord)0.5 * state->lineWidth * dyPrev;
	  break;
	}
      }
    } else {
      dxPrev = dx;
      dyPrev = dy;
      wdxPrev = wdx;
      wdyPrev = wdy;
    }

    // compute deltas for this line segment
    d = splashDist(seg->x0, seg->y0, seg->x1, seg->y1);
    if (d == 0) {
      // we need to draw end caps on zero-length lines
      //~ not clear what the behavior should be for splashLineCapButt with d==0
      dx = 0;
      dy = 1;
    } else {
      d = (SplashCoord)1 / d;
      dx = d * (seg->x1 - seg->x0);
      dy = d * (seg->y1 - seg->y0);
    }
    wdx = (SplashCoord)0.5 * state->lineWidth * dx;
    wdy = (SplashCoord)0.5 * state->lineWidth * dy;

    // initialize the path (which will be filled)
    widePath = new SplashPath();
    widePath->moveTo(seg->x0 - wdy, seg->y0 + wdx);

    // draw the start cap
    if (seg->flags & splashXPathEnd0) {
      switch (state->lineCap) {
      case splashLineCapButt:
	widePath->lineTo(seg->x0 + wdy, seg->y0 - wdx);
	break;
      case splashLineCapRound:
	widePath->arcCWTo(seg->x0 + wdy, seg->y0 - wdx, seg->x0, seg->y0);
	break;
      case splashLineCapProjecting:
	widePath->lineTo(seg->x0 - wdx - wdy, seg->y0 + wdx - wdy);
	widePath->lineTo(seg->x0 - wdx + wdy, seg->y0 - wdx - wdy);
	widePath->lineTo(seg->x0 + wdy, seg->y0 - wdx);
	break;
      }
    } else {
      widePath->lineTo(seg->x0 + wdy, seg->y0 - wdx);
    }

    // draw the left side of the segment
    widePath->lineTo(seg->x1 + wdy, seg->y1 - wdx);

    // draw the end cap
    if (seg->flags & splashXPathEnd1) {
      switch (state->lineCap) {
      case splashLineCapButt:
	widePath->lineTo(seg->x1 - wdy, seg->y1 + wdx);
	break;
      case splashLineCapRound:
	widePath->arcCWTo(seg->x1 - wdy, seg->y1 + wdx, seg->x1, seg->y1);
	break;
      case splashLineCapProjecting:
	widePath->lineTo(seg->x1 + wdx + wdy, seg->y1 - wdx + wdy);
	widePath->lineTo(seg->x1 + wdx - wdy, seg->y1 + wdx + wdy);
	widePath->lineTo(seg->x1 - wdy, seg->y1 + wdx);
	break;
      }
    } else {
      widePath->lineTo(seg->x1 - wdy, seg->y1 + wdx);
    }

    // draw the right side of the segment
    widePath->lineTo(seg->x0 - wdy, seg->y0 + wdx);

    // fill the segment
    fillWithPattern(widePath, gTrue, state->strokePattern, state->strokeAlpha);
    delete widePath;

    // draw the line join
    if (!(seg->flags & splashXPathEnd0)) {
      widePath = NULL;
      switch (state->lineJoin) {
      case splashLineJoinMiter:
	dotprod = -(dx * dxPrev + dy * dyPrev);
	if (splashAbs(splashAbs(dotprod) - 1) > 0.01) {
	  widePath = new SplashPath();
	  widePath->moveTo(seg->x0, seg->y0);
	  miter = (SplashCoord)2 / ((SplashCoord)1 - dotprod);
	  if (splashSqrt(miter) <= state->miterLimit) {
	    miter = splashSqrt(miter - 1);
	    if (dy * dxPrev > dx * dyPrev) {
	      widePath->lineTo(seg->x0 + wdyPrev, seg->y0 - wdxPrev);
	      widePath->lineTo(seg->x0 + wdy - miter * wdx,
			       seg->y0 - wdx - miter * wdy);
	      widePath->lineTo(seg->x0 + wdy, seg->y0 - wdx);
	    } else {
	      widePath->lineTo(seg->x0 - wdyPrev, seg->y0 + wdxPrev);
	      widePath->lineTo(seg->x0 - wdy - miter * wdx,
			       seg->y0 + wdx - miter * wdy);
	      widePath->lineTo(seg->x0 - wdy, seg->y0 + wdx);
	    }
	  } else {
	    if (dy * dxPrev > dx * dyPrev) {
	      widePath->lineTo(seg->x0 + wdyPrev, seg->y0 - wdxPrev);
	      widePath->lineTo(seg->x0 + wdy, seg->y0 - wdx);
	    } else {
	      widePath->lineTo(seg->x0 - wdyPrev, seg->y0 + wdxPrev);
	      widePath->lineTo(seg->x0 - wdy, seg->y0 + wdx);
	    }
	  }
	}
	break;
      case splashLineJoinRound:
	widePath = new SplashPath();
	widePath->moveTo(seg->x0 + wdy, seg->y0 - wdx);
	widePath->arcCWTo(seg->x0 + wdy, seg->y0 - wdx, seg->x0, seg->y0);
	break;
      case splashLineJoinBevel:
	widePath = new SplashPath();
	widePath->moveTo(seg->x0, seg->y0);
	if (dy * dxPrev > dx * dyPrev) {
	  widePath->lineTo(seg->x0 + wdyPrev, seg->y0 - wdxPrev);
	  widePath->lineTo(seg->x0 + wdy, seg->y0 - wdx);
	} else {
	  widePath->lineTo(seg->x0 - wdyPrev, seg->y0 + wdxPrev);
	  widePath->lineTo(seg->x0 - wdy, seg->y0 + wdx);
	}
	break;
      }
      if (widePath) {
	fillWithPattern(widePath, gTrue, state->strokePattern,
			state->strokeAlpha);
	delete widePath;
      }
    }
  }
}

SplashXPath *Splash::makeDashedPath(SplashXPath *xPath) {
  SplashXPath *dPath;
  GBool lineDashStartOn, lineDashOn;
  GBool atSegStart, atSegEnd, atDashStart, atDashEnd;
  int lineDashStartIdx, lineDashIdx, subpathStart;
  SplashCoord lineDashTotal, lineDashStartPhase, lineDashDist;
  int segIdx;
  SplashXPathSeg *seg;
  SplashCoord sx0, sy0, sx1, sy1, ax0, ay0, ax1, ay1, dist;
  int i;

  dPath = new SplashXPath();

  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;
  }

  segIdx = 0;
  seg = xPath->segs;
  sx0 = seg->x0;
  sy0 = seg->y0;
  sx1 = seg->x1;
  sy1 = seg->y1;
  dist = splashDist(sx0, sy0, sx1, sy1);
  lineDashOn = lineDashStartOn;
  lineDashIdx = lineDashStartIdx;
  lineDashDist = state->lineDash[lineDashIdx] - lineDashStartPhase;
  atSegStart = gTrue;
  atDashStart = gTrue;
  subpathStart = dPath->length;

  while (segIdx < xPath->length) {

    ax0 = sx0;
    ay0 = sy0;
    if (dist <= lineDashDist) {
      ax1 = sx1;
      ay1 = sy1;
      lineDashDist -= dist;
      dist = 0;
      atSegEnd = gTrue;
      atDashEnd = lineDashDist == 0 || (seg->flags & splashXPathLast);
    } else {
      ax1 = sx0 + (lineDashDist / dist) * (sx1 - sx0);
      ay1 = sy0 + (lineDashDist / dist) * (sy1 - sy0);
      sx0 = ax1;
      sy0 = ay1;
      dist -= lineDashDist;
      lineDashDist = 0;
      atSegEnd = gFalse;
      atDashEnd = gTrue;
    }

    if (lineDashOn) {
      dPath->addSegment(ax0, ay0, ax1, ay1,
			atDashStart, atDashEnd,
			atDashStart, atDashEnd);
      // end of closed subpath
      if (atSegEnd &&
	  (seg->flags & splashXPathLast) &&
	  !(seg->flags & splashXPathEnd1)) {
	dPath->segs[subpathStart].flags &= ~splashXPathEnd0;
	dPath->segs[dPath->length - 1].flags &= ~splashXPathEnd1;
      }
    }

    if (atDashEnd) {
      lineDashOn = !lineDashOn;
      if (++lineDashIdx == state->lineDashLength) {
	lineDashIdx = 0;
      }
      lineDashDist = state->lineDash[lineDashIdx];
      atDashStart = gTrue;
    } else {
      atDashStart = gFalse;
    }
    if (atSegEnd) {
      if (++segIdx < xPath->length) {
	++seg;
	sx0 = seg->x0;
	sy0 = seg->y0;
	sx1 = seg->x1;
	sy1 = seg->y1;
	dist = splashDist(sx0, sy0, sx1, sy1);
	if (seg->flags & splashXPathFirst) {
	  lineDashOn = lineDashStartOn;
	  lineDashIdx = lineDashStartIdx;
	  lineDashDist = state->lineDash[lineDashIdx] - lineDashStartPhase;
	  atDashStart = gTrue;
	  subpathStart = dPath->length;
	}
      }
      atSegStart = gTrue;
    } else {
      atSegStart = gFalse;
    }
  }

  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) {
  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->flatness, gTrue);
  xPath->sort();
  scanner = new SplashXPathScanner(xPath, eo);

  // get the min and max x and y values
  scanner->getBBox(&xMinI, &yMinI, &xMaxI, &yMaxI);

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

    // limit the y range
    if (yMinI < state->clip->getYMin()) {
      yMinI = state->clip->getYMin();
    }
    if (yMaxI > state->clip->getYMax()) {
      yMaxI = state->clip->getYMax();
    }

    // draw the spans
    for (y = yMinI; y <= yMaxI; ++y) {
      while (scanner->getNextSpan(y, &x0, &x1)) {
	if (clipRes == splashClipAllInside) {
	  drawSpan(x0, x1, y, pattern, alpha, gTrue);
	} else {
	  // limit the x range
	  if (x0 < state->clip->getXMin()) {
	    x0 = state->clip->getXMin();
	  }
	  if (x1 > state->clip->getXMax()) {
	    x1 = state->clip->getXMax();
	  }
	  clipRes2 = state->clip->testSpan(x0, x1, y);
	  drawSpan(x0, x1, y, pattern, alpha, clipRes2 == splashClipAllInside);
	}
      }
    }
  }
  opClipRes = clipRes;

  delete scanner;
  delete xPath;
  return splashOk;
}

SplashError Splash::xorFill(SplashPath *path, GBool eo) {
  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->flatness, gTrue);
  xPath->sort();
  scanner = new SplashXPathScanner(xPath, eo);

  // get the min and max x and y values
  scanner->getBBox(&xMinI, &yMinI, &xMaxI, &yMaxI);

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

    // limit the y range
    if (yMinI < state->clip->getYMin()) {
      yMinI = state->clip->getYMin();
    }
    if (yMaxI > state->clip->getYMax()) {
      yMaxI = state->clip->getYMax();
    }

    // draw the spans
    for (y = yMinI; y <= yMaxI; ++y) {
      while (scanner->getNextSpan(y, &x0, &x1)) {
	if (clipRes == splashClipAllInside) {
	  xorSpan(x0, x1, y, state->fillPattern, gTrue);
	} else {
	  // limit the x range
	  if (x0 < state->clip->getXMin()) {
	    x0 = state->clip->getXMin();
	  }
	  if (x1 > state->clip->getXMax()) {
	    x1 = state->clip->getXMax();
	  }
	  clipRes2 = state->clip->testSpan(x0, x1, y);
	  xorSpan(x0, x1, y, state->fillPattern,
		  clipRes2 == splashClipAllInside);
	}
      }
    }
  }
  opClipRes = clipRes;

  delete scanner;
  delete xPath;
  return splashOk;
}

void Splash::drawPixel(int x, int y, SplashColorPtr color,
		       SplashCoord alpha, GBool noClip) {
  SplashBlendFunc blendFunc;
  SplashColorPtr p;
  SplashColor dest, blend;
  int alpha2, ialpha2;
  Guchar t;

  if (noClip || state->clip->test(x, y)) {
    if (alpha != 1 || softMask || state->blendFunc) {
      blendFunc = state->blendFunc ? state->blendFunc : &blendNormal;
      if (softMask) {
	alpha2 = (int)(alpha * softMask->data[y * softMask->rowSize + x]);
      } else {
	alpha2 = (int)(alpha * 255);
      }
      ialpha2 = 255 - alpha2;
      switch (bitmap->mode) {
      case splashModeMono1:
	p = &bitmap->data[y * bitmap->rowSize + (x >> 3)];
	dest[0] = (*p >> (7 - (x & 7))) & 1;
	(*blendFunc)(color, dest, blend, bitmap->mode);
	t = (alpha2 * blend[0] + ialpha2 * dest[0]) >> 8;
	if (t) {
	  *p |= 0x80 >> (x & 7);
	} else {
	  *p &= ~(0x80 >> (x & 7));
	}
	break;
      case splashModeMono8:
	p = &bitmap->data[y * bitmap->rowSize + x];
	(*blendFunc)(color, p, blend, bitmap->mode);
	// note: floor(x / 255) = x >> 8 (for 16-bit x)
	p[0] = (alpha2 * blend[0] + ialpha2 * p[0]) >> 8;
	break;
      case splashModeAMono8:
	p = &bitmap->data[y * bitmap->rowSize + 2 * x];
	(*blendFunc)(color, p, blend, bitmap->mode);
	p[0] = (alpha2 * blend[0] + ialpha2 * p[0]) >> 8;
	p[1] = (alpha2 * blend[1] + ialpha2 * p[1]) >> 8;
	break;
      case splashModeRGB8:
      case splashModeBGR8:
	p = &bitmap->data[y * bitmap->rowSize + 3 * x];
	(*blendFunc)(color, p, blend, bitmap->mode);
	p[0] = (alpha2 * blend[0] + ialpha2 * p[0]) >> 8;
	p[1] = (alpha2 * blend[1] + ialpha2 * p[1]) >> 8;
	p[2] = (alpha2 * blend[2] + ialpha2 * p[2]) >> 8;
	break;
      case splashModeARGB8:
      case splashModeBGRA8:
#if SPLASH_CMYK
      case splashModeCMYK8:
#endif
	p = &bitmap->data[y * bitmap->rowSize + 4 * x];
	(*blendFunc)(color, p, blend, bitmap->mode);
	p[0] = (alpha2 * blend[0] + ialpha2 * p[0]) >> 8;
	p[1] = (alpha2 * blend[1] + ialpha2 * p[1]) >> 8;
	p[2] = (alpha2 * blend[2] + ialpha2 * p[2]) >> 8;