gfx.cc

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  ignoreUndef = 0;
  for (i = 0; i < 6; ++i) {
    baseMatrix[i] = state->getCTM()[i];
  }
  formDepth = 0;
  abortCheckCbk = abortCheckCbkA;
  abortCheckCbkData = abortCheckCbkDataA;

  // set crop box
  if (cropBox) {
    state->moveTo(cropBox->x1, cropBox->y1);
    state->lineTo(cropBox->x2, cropBox->y1);
    state->lineTo(cropBox->x2, cropBox->y2);
    state->lineTo(cropBox->x1, cropBox->y2);
    state->closePath();
    state->clip();
    out->clip(state);
    state->clearPath();
  }
}

Gfx::~Gfx() {
  while (state->hasSaves()) {
    restoreState();
  }
  if (!subPage) {
    out->endPage();
  }
  while (res) {
    popResources();
  }
  if (state) {
    delete state;
  }
}

void Gfx::display(Object *obj, GBool topLevel) {
  Object obj2;
  int i;

  if (obj->isArray()) {
    for (i = 0; i < obj->arrayGetLength(); ++i) {
      obj->arrayGet(i, &obj2);
      if (!obj2.isStream()) {
	error(-1, "Weird page contents");
	obj2.free();
	return;
      }
      obj2.free();
    }
  } else if (!obj->isStream()) {
    error(-1, "Weird page contents");
    return;
  }
  parser = new Parser(xref, new Lexer(xref, obj), gFalse);
  go(topLevel);
  delete parser;
  parser = NULL;
}

void Gfx::go(GBool topLevel) {
  Object obj;
  Object args[maxArgs];
  int numArgs, i;
  int lastAbortCheck;

  // scan a sequence of objects
  updateLevel = lastAbortCheck = 0;
  numArgs = 0;
  parser->getObj(&obj);
  while (!obj.isEOF()) {

    // got a command - execute it
    if (obj.isCmd()) {
      if (printCommands) {
	obj.print(stdout);
	for (i = 0; i < numArgs; ++i) {
	  printf(" ");
	  args[i].print(stdout);
	}
	printf("\n");
	fflush(stdout);
      }
      execOp(&obj, args, numArgs);
      obj.free();
      for (i = 0; i < numArgs; ++i)
	args[i].free();
      numArgs = 0;

      // periodically update display
      if (++updateLevel >= 20000) {
	out->dump();
	updateLevel = 0;
      }

      // check for an abort
      if (abortCheckCbk) {
	if (updateLevel - lastAbortCheck > 10) {
	  if ((*abortCheckCbk)(abortCheckCbkData)) {
	    break;
	  }
	  lastAbortCheck = updateLevel;
	}
      }

    // got an argument - save it
    } else if (numArgs < maxArgs) {
      args[numArgs++] = obj;

    // too many arguments - something is wrong
    } else {
      error(getPos(), "Too many args in content stream");
      if (printCommands) {
	printf("throwing away arg: ");
	obj.print(stdout);
	printf("\n");
	fflush(stdout);
      }
      obj.free();
    }

    // grab the next object
    parser->getObj(&obj);
  }
  obj.free();

  // args at end with no command
  if (numArgs > 0) {
    error(getPos(), "Leftover args in content stream");
    if (printCommands) {
      printf("%d leftovers:", numArgs);
      for (i = 0; i < numArgs; ++i) {
	printf(" ");
	args[i].print(stdout);
      }
      printf("\n");
      fflush(stdout);
    }
    for (i = 0; i < numArgs; ++i)
      args[i].free();
  }

  // update display
  if (topLevel && updateLevel > 0) {
    out->dump();
  }
}

void Gfx::execOp(Object *cmd, Object args[], int numArgs) {
  Operator *op;
  char *name;
  Object *argPtr;
  int i;

  // find operator
  name = cmd->getCmd();
  if (!(op = findOp(name))) {
    if (ignoreUndef == 0)
      error(getPos(), "Unknown operator '%s'", name);
    return;
  }

  // type check args
  argPtr = args;
  if (op->numArgs >= 0) {
    if (numArgs < op->numArgs) {
      error(getPos(), "Too few (%d) args to '%s' operator", numArgs, name);
      return;
    }
    if (numArgs > op->numArgs) {
#if 0
      error(getPos(), "Too many (%d) args to '%s' operator", numArgs, name);
#endif
      argPtr += numArgs - op->numArgs;
      numArgs = op->numArgs;
    }
  } else {
    if (numArgs > -op->numArgs) {
      error(getPos(), "Too many (%d) args to '%s' operator",
	    numArgs, name);
      return;
    }
  }
  for (i = 0; i < numArgs; ++i) {
    if (!checkArg(&argPtr[i], op->tchk[i])) {
      error(getPos(), "Arg #%d to '%s' operator is wrong type (%s)",
	    i, name, argPtr[i].getTypeName());
      return;
    }
  }

  // do it
  (this->*op->func)(argPtr, numArgs);
}

Operator *Gfx::findOp(char *name) {
  int a, b, m, cmp;

  a = -1;
  b = numOps;
  // invariant: opTab[a] < name < opTab[b]
  while (b - a > 1) {
    m = (a + b) / 2;
    cmp = strcmp(opTab[m].name, name);
    if (cmp < 0)
      a = m;
    else if (cmp > 0)
      b = m;
    else
      a = b = m;
  }
  if (cmp != 0)
    return NULL;
  return &opTab[a];
}

GBool Gfx::checkArg(Object *arg, TchkType type) {
  switch (type) {
  case tchkBool:   return arg->isBool();
  case tchkInt:    return arg->isInt();
  case tchkNum:    return arg->isNum();
  case tchkString: return arg->isString();
  case tchkName:   return arg->isName();
  case tchkArray:  return arg->isArray();
  case tchkProps:  return arg->isDict() || arg->isName();
  case tchkSCN:    return arg->isNum() || arg->isName();
  case tchkNone:   return gFalse;
  }
  return gFalse;
}

int Gfx::getPos() {
  return parser ? parser->getPos() : -1;
}

//------------------------------------------------------------------------
// graphics state operators
//------------------------------------------------------------------------

void Gfx::opSave(Object args[], int numArgs) {
  saveState();
}

void Gfx::opRestore(Object args[], int numArgs) {
  restoreState();
}

void Gfx::opConcat(Object args[], int numArgs) {
  state->concatCTM(args[0].getNum(), args[1].getNum(),
		   args[2].getNum(), args[3].getNum(),
		   args[4].getNum(), args[5].getNum());
  out->updateCTM(state, args[0].getNum(), args[1].getNum(),
		 args[2].getNum(), args[3].getNum(),
		 args[4].getNum(), args[5].getNum());
  fontChanged = gTrue;
}

void Gfx::opSetDash(Object args[], int numArgs) {
  Array *a;
  int length;
  Object obj;
  double *dash;
  int i;

  a = args[0].getArray();
  length = a->getLength();
  if (length == 0) {
    dash = NULL;
  } else {
    dash = (double *)gmallocn(length, sizeof(double));
    for (i = 0; i < length; ++i) {
      dash[i] = a->get(i, &obj)->getNum();
      obj.free();
    }
  }
  state->setLineDash(dash, length, args[1].getNum());
  out->updateLineDash(state);
}

void Gfx::opSetFlat(Object args[], int numArgs) {
  state->setFlatness((int)args[0].getNum());
  out->updateFlatness(state);
}

void Gfx::opSetLineJoin(Object args[], int numArgs) {
  state->setLineJoin(args[0].getInt());
  out->updateLineJoin(state);
}

void Gfx::opSetLineCap(Object args[], int numArgs) {
  state->setLineCap(args[0].getInt());
  out->updateLineCap(state);
}

void Gfx::opSetMiterLimit(Object args[], int numArgs) {
  state->setMiterLimit(args[0].getNum());
  out->updateMiterLimit(state);
}

void Gfx::opSetLineWidth(Object args[], int numArgs) {
  state->setLineWidth(args[0].getNum());
  out->updateLineWidth(state);
}

void Gfx::opSetExtGState(Object args[], int numArgs) {
  Object obj1, obj2, obj3, obj4, obj5;
  GfxBlendMode mode;
  GBool haveFillOP;
  Function *funcs[4];
  GfxColor backdropColor;
  GBool haveBackdropColor;
  GfxColorSpace *blendingColorSpace;
  GBool alpha, isolated, knockout;
  int i;

  if (!res->lookupGState(args[0].getName(), &obj1)) {
    return;
  }
  if (!obj1.isDict()) {
    error(getPos(), "ExtGState '%s' is wrong type", args[0].getName());
    obj1.free();
    return;
  }
  if (printCommands) {
    printf("  gfx state dict: ");
    obj1.print();
    printf("\n");
  }

  // transparency support: blend mode, fill/stroke opacity
  if (!obj1.dictLookup("BM", &obj2)->isNull()) {
    if (state->parseBlendMode(&obj2, &mode)) {
      state->setBlendMode(mode);
      out->updateBlendMode(state);
    } else {
      error(getPos(), "Invalid blend mode in ExtGState");
    }
  }
  obj2.free();
  if (obj1.dictLookup("ca", &obj2)->isNum()) {
    state->setFillOpacity(obj2.getNum());
    out->updateFillOpacity(state);
  }
  obj2.free();
  if (obj1.dictLookup("CA", &obj2)->isNum()) {
    state->setStrokeOpacity(obj2.getNum());
    out->updateStrokeOpacity(state);
  }
  obj2.free();

  // fill/stroke overprint
  if ((haveFillOP = (obj1.dictLookup("op", &obj2)->isBool()))) {
    state->setFillOverprint(obj2.getBool());
    out->updateFillOverprint(state);
  }
  obj2.free();
  if (obj1.dictLookup("OP", &obj2)->isBool()) {
    state->setStrokeOverprint(obj2.getBool());
    out->updateStrokeOverprint(state);
    if (!haveFillOP) {
      state->setFillOverprint(obj2.getBool());
      out->updateFillOverprint(state);
    }
  }
  obj2.free();

  // stroke adjust
  if (obj1.dictLookup("SA", &obj2)->isBool()) {
    state->setStrokeAdjust(obj2.getBool());
    out->updateStrokeAdjust(state);
  }
  obj2.free();

  // transfer function
  if (obj1.dictLookup("TR2", &obj2)->isNull()) {
    obj2.free();
    obj1.dictLookup("TR", &obj2);
  }
  if (obj2.isName("Default") ||
      obj2.isName("Identity")) {
    funcs[0] = funcs[1] = funcs[2] = funcs[3] = NULL;
    state->setTransfer(funcs);
    out->updateTransfer(state);
  } else if (obj2.isArray() && obj2.arrayGetLength() == 4) {
    for (i = 0; i < 4; ++i) {
      obj2.arrayGet(i, &obj3);
      funcs[i] = Function::parse(&obj3);
      obj3.free();
      if (!funcs[i]) {
	break;
      }
    }
    if (i == 4) {
      state->setTransfer(funcs);
      out->updateTransfer(state);
    }
  } else if (obj2.isName() || obj2.isDict() || obj2.isStream()) {
    if ((funcs[0] = Function::parse(&obj2))) {
      funcs[1] = funcs[2] = funcs[3] = NULL;
      state->setTransfer(funcs);
      out->updateTransfer(state);
    }
  } else if (!obj2.isNull()) {
    error(getPos(), "Invalid transfer function in ExtGState");
  }
  obj2.free();

  // soft mask
  if (!obj1.dictLookup("SMask", &obj2)->isNull()) {
    if (obj2.isName("None")) {
      out->clearSoftMask(state);
    } else if (obj2.isDict()) {
      if (obj2.dictLookup("S", &obj3)->isName("Alpha")) {
	alpha = gTrue;
      } else { // "Luminosity"
	alpha = gFalse;
      }
      obj3.free();
      funcs[0] = NULL;
      if (!obj2.dictLookup("TR", &obj3)->isNull()) {
	funcs[0] = Function::parse(&obj3);
	if (funcs[0]->getInputSize() != 1 ||
	    funcs[0]->getOutputSize() != 1) {
	  error(getPos(),
		"Invalid transfer function in soft mask in ExtGState");
	  delete funcs[0];
	  funcs[0] = NULL;
	}
      }
      obj3.free();
      if ((haveBackdropColor = obj2.dictLookup("BC", &obj3)->isArray())) {
	for (i = 0; i < gfxColorMaxComps; ++i) {
	  backdropColor.c[i] = 0;
	}
	for (i = 0; i < obj3.arrayGetLength() && i < gfxColorMaxComps; ++i) {
	  obj3.arrayGet(i, &obj4);
	  if (obj4.isNum()) {
	    backdropColor.c[i] = dblToCol(obj4.getNum());
	  }
	  obj4.free();
	}
      }
      obj3.free();
      if (obj2.dictLookup("G", &obj3)->isStream()) {
	if (obj3.streamGetDict()->lookup("Group", &obj4)->isDict()) {
	  blendingColorSpace = NULL;
	  isolated = knockout = gFalse;
	  if (!obj4.dictLookup("CS", &obj5)->isNull()) {
	    blendingColorSpace = GfxColorSpace::parse(&obj5);
	  }
	  obj5.free();
	  if (obj4.dictLookup("I", &obj5)->isBool()) {
	    isolated = obj5.getBool();
	  }
	  obj5.free();
	  if (obj4.dictLookup("K", &obj5)->isBool()) {
	    knockout = obj5.getBool();
	  }
	  obj5.free();
	  if (!haveBackdropColor) {
	    if (blendingColorSpace) {
	      blendingColorSpace->getDefaultColor(&backdropColor);
	    } else {
	      //~ need to get the parent or default color space (?)
	      for (i = 0; i < gfxColorMaxComps; ++i) {
		backdropColor.c[i] = 0;
	      }
	    }
	  }
	  doSoftMask(&obj3, alpha, blendingColorSpace,
		     isolated, knockout, funcs[0], &backdropColor);
	  if (funcs[0]) {
	    delete funcs[0];
	  }
	} else {
	  error(getPos(), "Invalid soft mask in ExtGState - missing group");
	}
	obj4.free();
      } else {
	error(getPos(), "Invalid soft mask in ExtGState - missing group");
      }
      obj3.free();
    } else if (!obj2.isNull()) {
      error(getPos(), "Invalid soft mask in ExtGState");
    }
  }
  obj2.free();

  obj1.free();
}

void Gfx::doSoftMask(Object *str, GBool alpha,
		     GfxColorSpace *blendingColorSpace,
		     GBool isolated, GBool knockout,
		     Function *transferFunc, GfxColor *backdropColor) {
  Dict *dict, *resDict;
  double m[6], bbox[4];
  Object obj1, obj2;
  int i;

  // check for excessive recursion
  if (formDepth > 20) {
    return;