gfx.cc

来自「source code: Covert TXT to PDF」· CC 代码 · 共 2,586 行 · 第 1/5 页

      }
      if (k == nComps) {
	break;
      }
      k = (i + j) / 2;
      ta[k] = 0.5 * (ta[i] + ta[j]);
      next[i] = k;
      next[k] = j;
      j = k;
    }

    // use the average of the colors of the two sides of the region
    for (k = 0; k < nComps; ++k) {
      color0.c[k] = 0.5 * (color0.c[k] + color1.c[k]);
    }

    // compute the coordinates of the point on the t axis; then
    // compute the intersection of the perpendicular line with the
    // bounding box
    tx = x0 + ta[j] * dx;
    ty = y0 + ta[j] * dy;
    if (dx == 0 && dy == 0) {
      sMin = sMax = 0;
    } if (dx == 0) {
      sMin = (xMin - tx) / -dy;
      sMax = (xMax - tx) / -dy;
      if (sMin > sMax) { tmp = sMin; sMin = sMax; sMax = tmp; }
    } else if (dy == 0) {
      sMin = (yMin - ty) / dx;
      sMax = (yMax - ty) / dx;
      if (sMin > sMax) { tmp = sMin; sMin = sMax; sMax = tmp; }
    } else {
      s[0] = (yMin - ty) / dx;
      s[1] = (yMax - ty) / dx;
      s[2] = (xMin - tx) / -dy;
      s[3] = (xMax - tx) / -dy;
      for (j = 0; j < 3; ++j) {
	kk = j;
	for (k = j + 1; k < 4; ++k) {
	  if (s[k] < s[kk]) {
	    kk = k;
	  }
	}
	tmp = s[j]; s[j] = s[kk]; s[kk] = tmp;
      }
      sMin = s[1];
      sMax = s[2];
    }
    ux1 = tx - sMin * dy;
    uy1 = ty + sMin * dx;
    vx1 = tx - sMax * dy;
    vy1 = ty + sMax * dx;

    // set the color
    state->setFillColor(&color0);
    out->updateFillColor(state);

    // fill the region
    state->moveTo(ux0, uy0);
    state->lineTo(vx0, vy0);
    state->lineTo(vx1, vy1);
    state->lineTo(ux1, uy1);
    state->closePath();
    out->fill(state);
    state->clearPath();

    // set up for next region
    ux0 = ux1;
    uy0 = uy1;
    vx0 = vx1;
    vy0 = vy1;
    color0 = color1;
    i = next[i];
  }
}

void Gfx::doRadialShFill(GfxRadialShading *shading) {
  double sMin, sMax, xMin, yMin, xMax, yMax;
  double x0, y0, r0, x1, y1, r1, t0, t1;
  int nComps;
  GfxColor colorA, colorB;
  double xa, ya, xb, yb, ra, rb;
  double ta, tb, sa, sb;
  int ia, ib, k, n;
  double *ctm;
  double angle, t;

  // get the shading info
  shading->getCoords(&x0, &y0, &r0, &x1, &y1, &r1);
  t0 = shading->getDomain0();
  t1 = shading->getDomain1();
  nComps = shading->getColorSpace()->getNComps();

  // compute the (possibly extended) s range
  sMin = 0;
  sMax = 1;
  if (shading->getExtend0()) {
    if (r0 < r1) {
      // extend the smaller end
      sMin = -r0 / (r1 - r0);
    } else {
      // extend the larger end
      //~ this computes the diagonal of the bounding box -- we should
      //~ really compute the intersection of the moving/expanding
      //~ circles with each of the four corners and look for the max
      //~ radius
      state->getUserClipBBox(&xMin, &yMin, &xMax, &yMax);
      sMin = (sqrt((xMax - xMin) * (xMax - xMin) +
		   (yMax - yMin) * (yMax - yMin)) - r0) / (r1 - r0);
      if (sMin > 0) {
	sMin = 0;
      } else if (sMin < -20) {
	// sanity check
	sMin = -20;
      }
    }
  }
  if (shading->getExtend1()) {
    if (r1 < r0) {
      // extend the smaller end
      sMax = -r0 / (r1 - r0);
    } else if (r1 > r0) {
      // extend the larger end
      state->getUserClipBBox(&xMin, &yMin, &xMax, &yMax);
      sMax = (sqrt((xMax - xMin) * (xMax - xMin) +
		   (yMax - yMin) * (yMax - yMin)) - r0) / (r1 - r0);
      if (sMax < 1) {
	sMin = 1;
      } else if (sMax > 20) {
	// sanity check
	sMax = 20;
      }
    }
  }

  // compute the number of steps into which circles must be divided to
  // achieve a curve flatness of 0.1 pixel in device space for the
  // largest circle (note that "device space" is 72 dpi when generating
  // PostScript, hence the relatively small 0.1 pixel accuracy)
  ctm = state->getCTM();
  t = fabs(ctm[0]);
  if (fabs(ctm[1]) > t) {
    t = fabs(ctm[1]);
  }
  if (fabs(ctm[2]) > t) {
    t = fabs(ctm[2]);
  }
  if (fabs(ctm[3]) > t) {
    t = fabs(ctm[3]);
  }
  if (r0 > r1) {
    t *= r0;
  } else {
    t *= r1;
  }
  if (t < 1) {
    n = 3;
  } else {
    n = (int)(M_PI / acos(1 - 0.1 / t));
    if (n < 3) {
      n = 3;
    } else if (n > 200) {
      n = 200;
    }
  }

  // Traverse the t axis and do the shading.
  //
  // This generates and fills a series of rings.  Each ring is defined
  // by two circles:
  //   sa, ta, xa, ya, ra, colorA
  //   sb, tb, xb, yb, rb, colorB
  //
  // The s/t axis is divided into radialMaxSplits parts; these parts
  // are combined as much as possible while respecting the
  // radialColorDelta parameter.

  // setup for the start circle
  ia = 0;
  sa = sMin;
  ta = t0 + sa * (t1 - t0);
  xa = x0 + sa * (x1 - x0);
  ya = y0 + sa * (y1 - y0);
  ra = r0 + sa * (r1 - r0);
  if (ta < t0) {
    shading->getColor(t0, &colorA);
  } else if (ta > t1) {
    shading->getColor(t1, &colorA);
  } else {
    shading->getColor(ta, &colorA);
  }

  while (ia < radialMaxSplits) {

    // go as far along the t axis (toward t1) as we can, such that the
    // color difference is within the tolerance (radialColorDelta) --
    // this uses bisection (between the current value, t, and t1),
    // limited to radialMaxSplits points along the t axis
    ib = radialMaxSplits;
    sb = sMin + ((double)ib / (double)radialMaxSplits) * (sMax - sMin);
    tb = t0 + sb * (t1 - t0);
    if (tb < t0) {
      shading->getColor(t0, &colorB);
    } else if (tb > t1) {
      shading->getColor(t1, &colorB);
    } else {
      shading->getColor(tb, &colorB);
    }
    while (ib - ia > 1) {
      for (k = 0; k < nComps; ++k) {
	if (fabs(colorB.c[k] - colorA.c[k]) > radialColorDelta) {
	  break;
	}
      }
      if (k == nComps) {
	break;
      }
      ib = (ia + ib) / 2;
      sb = sMin + ((double)ib / (double)radialMaxSplits) * (sMax - sMin);
      tb = t0 + sb * (t1 - t0);
      if (tb < t0) {
	shading->getColor(t0, &colorB);
      } else if (tb > t1) {
	shading->getColor(t1, &colorB);
      } else {
	shading->getColor(tb, &colorB);
      }
    }

    // compute center and radius of the circle
    xb = x0 + sb * (x1 - x0);
    yb = y0 + sb * (y1 - y0);
    rb = r0 + sb * (r1 - r0);

    // use the average of the colors at the two circles
    for (k = 0; k < nComps; ++k) {
      colorA.c[k] = 0.5 * (colorA.c[k] + colorB.c[k]);
    }
    state->setFillColor(&colorA);
    out->updateFillColor(state);

    // construct path for first circle
    state->moveTo(xa + ra, ya);
    for (k = 1; k < n; ++k) {
      angle = ((double)k / (double)n) * 2 * M_PI;
      state->lineTo(xa + ra * cos(angle), ya + ra * sin(angle));
    }
    state->closePath();

    // construct and append path for second circle
    state->moveTo(xb + rb, yb);
    for (k = 1; k < n; ++k) {
      angle = ((double)k / (double)n) * 2 * M_PI;
      state->lineTo(xb + rb * cos(angle), yb + rb * sin(angle));
    }
    state->closePath();

    // fill the ring
    out->eoFill(state);
    state->clearPath();

    // step to the next value of t
    ia = ib;
    sa = sb;
    ta = tb;
    xa = xb;
    ya = yb;
    ra = rb;
    colorA = colorB;
  }
}

void Gfx::doEndPath() {
  if (state->isCurPt() && clip != clipNone) {
    state->clip();
    if (clip == clipNormal) {
      out->clip(state);
    } else {
      out->eoClip(state);
    }
  }
  clip = clipNone;
  state->clearPath();
}

//------------------------------------------------------------------------
// path clipping operators
//------------------------------------------------------------------------

void Gfx::opClip(Object args[], int numArgs) {
  clip = clipNormal;
}

void Gfx::opEOClip(Object args[], int numArgs) {
  clip = clipEO;
}

//------------------------------------------------------------------------
// text object operators
//------------------------------------------------------------------------

void Gfx::opBeginText(Object args[], int numArgs) {
  state->setTextMat(1, 0, 0, 1, 0, 0);
  state->textMoveTo(0, 0);
  out->updateTextMat(state);
  out->updateTextPos(state);
  fontChanged = gTrue;
}

void Gfx::opEndText(Object args[], int numArgs) {
}

//------------------------------------------------------------------------
// text state operators
//------------------------------------------------------------------------

void Gfx::opSetCharSpacing(Object args[], int numArgs) {
  state->setCharSpace(args[0].getNum());
  out->updateCharSpace(state);
}

void Gfx::opSetFont(Object args[], int numArgs) {
  GfxFont *font;

  if (!(font = res->lookupFont(args[0].getName()))) {
    return;
  }
  if (printCommands) {
    printf("  font: tag=%s name='%s' %g\n",
	   font->getTag()->getCString(),
	   font->getName() ? font->getName()->getCString() : "???",
	   args[1].getNum());
    fflush(stdout);
  }
  state->setFont(font, args[1].getNum());
  fontChanged = gTrue;
}

void Gfx::opSetTextLeading(Object args[], int numArgs) {
  state->setLeading(args[0].getNum());
}

void Gfx::opSetTextRender(Object args[], int numArgs) {
  state->setRender(args[0].getInt());
  out->updateRender(state);
}

void Gfx::opSetTextRise(Object args[], int numArgs) {
  state->setRise(args[0].getNum());
  out->updateRise(state);
}

void Gfx::opSetWordSpacing(Object args[], int numArgs) {
  state->setWordSpace(args[0].getNum());
  out->updateWordSpace(state);
}

void Gfx::opSetHorizScaling(Object args[], int numArgs) {
  state->setHorizScaling(args[0].getNum());
  out->updateHorizScaling(state);
  fontChanged = gTrue;
}

//------------------------------------------------------------------------
// text positioning operators
//------------------------------------------------------------------------

void Gfx::opTextMove(Object args[], int numArgs) {
  double tx, ty;

  tx = state->getLineX() + args[0].getNum();
  ty = state->getLineY() + args[1].getNum();
  state->textMoveTo(tx, ty);
  out->updateTextPos(state);
}

void Gfx::opTextMoveSet(Object args[], int numArgs) {
  double tx, ty;

  tx = state->getLineX() + args[0].getNum();
  ty = args[1].getNum();
  state->setLeading(-ty);
  ty += state->getLineY();
  state->textMoveTo(tx, ty);
  out->updateTextPos(state);
}

void Gfx::opSetTextMatrix(Object args[], int numArgs) {
  state->setTextMat(args[0].getNum(), args[1].getNum(),
		    args[2].getNum(), args[3].getNum(),
		    args[4].getNum(), args[5].getNum());
  state->textMoveTo(0, 0);
  out->updateTextMat(state);
  out->updateTextPos(state);
  fontChanged = gTrue;
}

void Gfx::opTextNextLine(Object args[], int numArgs) {
  double tx, ty;

  tx = state->getLineX();
  ty = state->getLineY() - state->getLeading();
  state->textMoveTo(tx, ty);
  out->updateTextPos(state);
}

//------------------------------------------------------------------------
// text string operators
//------------------------------------------------------------------------

void Gfx::opShowText(Object args[], int numArgs) {
  if (!state->getFont()) {
    error(getPos(), "No font in show");
    return;
  }
  doShowText(args[0].getString());
}

void Gfx::opMoveShowText(Object args[], int numArgs) {
  double tx, ty;

  if (!state->getFont()) {
    error(getPos(), "No font in move/show");
    return;
  }
  tx = state->getLineX();
  ty = state->getLineY() - state->getLeading();
  state->textMoveTo(tx, ty);
  out->updateTextPos(state);
  doShowText(args[0].getString());
}

void Gfx::opMoveSetShowText(Object args[], int numArgs) {
  double tx, ty;

  if (!state->getFont()) {
    error(getPos(), "No font in move/set/show");
    return;
  }
  state->setWordSpace(args[0].getNum());
  state->setCharSpace(args[1].getNum());
  tx = state->getLineX();
  ty = state->getLineY() - state->getLeading();
  state->textMoveTo(tx, ty);
  out->updateWordSpace(state);
  out->updateCharSpace(state);
  out->updateTextPos(state);
  doShowText(args[2].getString());
}

void Gfx::opShowSpaceText(Object args[], int numArgs) {
  Array *a;
  Object obj;
  int wMode;
  int i;

  if (!state->getFont()) {
    error(getPos(), "No font in show/space");
    return;
  }
  wMode = state->getFont()->getWMode();
  a = args[0].getArray();
  for (i = 0; i < a->getLength(); ++i) {
    a->get(i, &obj);
    if (obj.isNum()) {
      if (wMode) {
	state->textShift(0, -obj.getNum() * 0.001 * state->getFontSize());
      } else {
	state->textShift(-obj.getNum() * 0.001 * state->getFontSize(), 0);
      }
      out->updateTextShift(state, obj.getNum());
    } else if (obj.isString()) {
      doShowText(obj.getString());
    } else {
      error(getPos(), "Element of show/space array must be number or string");
    }
    obj.free();
  }
}

void Gfx::doShowText(GString *s) {
  GfxFont *font;
  int wMode;
  double riseX, riseY;
  CharCode code;
  Unicode u[8];
  double x, y, dx, dy, dx2, dy2, curX, curY, tdx, tdy, lineX, lineY;
  double originX, originY, tOriginX, tOriginY;
  double oldCTM[6], newCTM[6];
  double *mat;
  Object charProc;
  Dict *resDict;
  Parser *oldParser;
  char *p;
  int len, n, uLen, nChars, nSpaces, i;

  if (fontChanged) {
    out->updateFont(state);
    fontChanged = gFalse;
  }
  font = state->getFont();
  wMode = font->getWMode();

  if (out->useDrawChar()) {
    out->beginString(state, s);
  }

  // handle a Type 3 char
  if (font->getType() == fontType3 && out->interpretType3Chars()) {
    mat = state->getCTM();
    for (i = 0; i < 6; ++i) {
      oldCTM[i] = mat[i];
    }
    mat = state->getTextMat();
    newCTM[0] = mat[0] * oldCTM[0] + mat[1] * oldCTM[2];
    newCTM[1] = mat[0] * oldCTM[1] + mat[1] * oldCTM[3];
    newCTM[2] = mat[2] * oldCTM[0] + mat[3] * oldCTM[2];
    newCTM[3] = mat[2] * oldCTM[1] + mat[3] * oldCTM[3];