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+/*************************************************************************
+** ColorSpecialHandler.cpp **
+** **
+** This file is part of dvisvgm -- a fast DVI to SVG converter **
+** Copyright (C) 2005-2019 Martin Gieseking <martin.gieseking@uos.de> **
+** **
+** This program is free software; you can redistribute it and/or **
+** modify it under the terms of the GNU General Public License as **
+** published by the Free Software Foundation; either version 3 of **
+** the License, or (at your option) any later version. **
+** **
+** This program is distributed in the hope that it will be useful, but **
+** WITHOUT ANY WARRANTY; without even the implied warranty of **
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the **
+** GNU General Public License for more details. **
+** **
+** You should have received a copy of the GNU General Public License **
+** along with this program; if not, see <http://www.gnu.org/licenses/>. **
+*************************************************************************/
+
+#include <cstring>
+#include <sstream>
+#include <vector>
+#include "ColorSpecialHandler.hpp"
+#include "SpecialActions.hpp"
+
+using namespace std;
+
+
+static double read_double (istream &is) {
+ is.clear();
+ double v;
+ is >> v;
+ if (is.fail())
+ throw SpecialException("number expected");
+ return v;
+}
+
+
+/** Reads multiple double values from a given stream. The number of
+ * values read is determined by the size of the result vector.
+ * @param[in] is stream to be read from
+ * @param[out] vec the resulting values */
+static void read_doubles (istream &is, vector<double> &vec) {
+ for (double &val : vec)
+ val = read_double(is);
+}
+
+
+/** Reads a color statement from an input stream and converts it to a color object.
+ * A color statement has the following syntax:
+ * _color model_ _component values_
+ * Currently, the following color models are supported: rgb, cmyk, hsb and gray.
+ * Examples: rgb 1 0.5 0, gray 0.5
+ * @param[in] model the color model
+ * @param[in] is stream to be read from
+ * @return resulting Color object */
+Color ColorSpecialHandler::readColor (const string &model, istream &is) {
+ Color color;
+ if (model == "rgb") {
+ vector<double> rgb(3);
+ read_doubles(is, rgb);
+ color.setRGB(rgb[0], rgb[1], rgb[2]);
+ }
+ else if (model == "cmyk") {
+ vector<double> cmyk(4);
+ read_doubles(is, cmyk);
+ color.setCMYK(cmyk[0], cmyk[1], cmyk[2], cmyk[3]);
+ }
+ else if (model == "hsb") {
+ vector<double> hsb(3);
+ read_doubles(is, hsb);
+ color.setHSB(hsb[0], hsb[1], hsb[2]);
+ }
+ else if (model == "gray")
+ color.setGray(read_double(is));
+ else if (!color.setPSName(model, true))
+ throw SpecialException("unknown color statement");
+ return color;
+}
+
+
+/** Reads the color model (rgb, cmyk, hsb, or gray) and the corresponding color compontents
+ * from a given input stream.
+ * @param[in] is stream to be read from
+ * @return resulting Color object */
+Color ColorSpecialHandler::readColor (istream &is) {
+ string model;
+ is >> model;
+ return readColor(model, is);
+}
+
+
+bool ColorSpecialHandler::process (const string&, istream &is, SpecialActions &actions) {
+ string cmd;
+ is >> cmd;
+ if (cmd == "push") // color push <model> <params>
+ _colorStack.push(readColor(is));
+ else if (cmd == "pop") {
+ if (!_colorStack.empty()) // color pop
+ _colorStack.pop();
+ }
+ else { // color <model> <params>
+ while (!_colorStack.empty())
+ _colorStack.pop();
+ _colorStack.push(readColor(cmd, is));
+ }
+ if (_colorStack.empty())
+ actions.setColor(Color::BLACK);
+ else
+ actions.setColor(_colorStack.top());
+ return true;
+}
+
+
+vector<const char*> ColorSpecialHandler::prefixes() const {
+ vector<const char*> pfx {"color"};
+ return pfx;
+}
+