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diff --git a/Build/source/texk/dvisvgm/dvisvgm-1.0.9/src/EmSpecialHandler.cpp b/Build/source/texk/dvisvgm/dvisvgm-1.0.9/src/EmSpecialHandler.cpp
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+/*************************************************************************
+** EmSpecialHandler.cpp **
+** **
+** This file is part of dvisvgm -- the DVI to SVG converter **
+** Copyright (C) 2005-2011 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 <sstream>
+#include "EmSpecialHandler.h"
+#include "InputBuffer.h"
+#include "InputReader.h"
+#include "SpecialActions.h"
+#include "XMLNode.h"
+
+using namespace std;
+
+
+EmSpecialHandler::EmSpecialHandler () : _linewidth(0.4), _actions(0) {
+}
+
+
+/** Computes the "cut vector" that is used to compute the line shape.
+ * Because each line has a width > 0 the actual shape of the line is a tetragon.
+ * The 4 vertices can be influenced by the cut parameter c that specifies
+ * a horizontal, vertical or orthogonal cut of a line end. Depending on c and the
+ * line's slope a cut vector v can be computed that, relatively to endpoint p, denotes
+ * the 2 vertices of that line end: v1=p+v and v2=p-v.
+ * @param[in] c cut direction ('h', 'v' or 'p')
+ * @param[in] v direction vector of line to be drawn
+ * @param[in] lw width of line to be drawn
+ * @return the "cut vector" */
+static DPair cut_vector (char c, const DPair &v, double lw) {
+ if (c == 'p')
+ return v.ortho()/v.length() * (lw/2);
+ DPair cut;
+ if (c == 'v' && v.x() != 0) {
+ double slope = v.y()/v.x();
+ double h = sqrt(lw*lw*(1+slope*slope));
+ cut.y(0.5*h);
+ }
+ else if (v.y() != 0) { // c == 'h'
+ double slope = v.x()/v.y();
+ double h = sqrt(lw*lw*(1+slope*slope));
+ double sgn = slope < 0 ? 1.0 : -1.0;
+ cut.x(0.5*h*sgn);
+ }
+ return cut;
+}
+
+
+/** Creates the SVG element that will a the line.
+ * @param[in] p1 first endpoint in TeX point units
+ * @param[in] p2 second endpoint in TeX point units
+ * @param[in] c1 cut method of first endpoint ('h', 'v' or 'p')
+ * @param[in] c2 cut method of second endpoint ('h', 'v' or 'p')
+ * @param[in] lw line width in TeX point units */
+static void create_line (const DPair &p1, const DPair &p2, char c1, char c2, double lw, SpecialActions *actions) {
+ XMLElementNode *node=0;
+ DPair dir = p2-p1;
+ if (dir.x() == 0 || dir.y() == 0 || (c1 == 'p' && c2 == 'p')) {
+ // draw regular line
+ node = new XMLElementNode("line");
+ node->addAttribute("x1", p1.x());
+ node->addAttribute("y1", p1.y());
+ node->addAttribute("x2", p2.x());
+ node->addAttribute("y2", p2.y());
+ node->addAttribute("stroke-width", lw);
+ node->addAttribute("stroke", actions->getColor().rgbString());
+ // update bounding box
+ actions->embed(p1);
+ actions->embed(p2);
+ }
+ else {
+ // draw polygon
+ DPair cv1 = cut_vector(c1, dir, lw);
+ DPair cv2 = cut_vector(c2, dir, lw);
+ DPair q11 = p1+cv1, q12 = p1-cv1;
+ DPair q21 = p2+cv2, q22 = p2-cv2;
+ node = new XMLElementNode("polygon");
+ ostringstream oss;
+ oss << q11.x() << ',' << q11.y() << ' '
+ << q12.x() << ',' << q12.y() << ' '
+ << q22.x() << ',' << q22.y() << ' '
+ << q21.x() << ',' << q21.y();
+ node->addAttribute("points", oss.str());
+ if (actions->getColor() != Color::BLACK)
+ node->addAttribute("fill", actions->getColor().rgbString());
+ // update bounding box
+ actions->embed(q11);
+ actions->embed(q12);
+ actions->embed(q21);
+ actions->embed(q22);
+ }
+ actions->appendToPage(node);
+}
+
+
+static double read_length (InputReader &in) {
+ struct Unit {
+ const char *name;
+ double factor;
+ }
+ units[] = {
+ {"pt", 1.0},
+ {"pc", 12.0},
+ {"in", 72.27},
+ {"bp", 72.27/72},
+ {"cm", 72.27/2.54},
+ {"mm", 72.27/25.4},
+ {"dd", 1238.0/1157},
+ {"cc", 1238.0/1157*12},
+ {"sp", 1.0/65536},
+ {0, 0}
+ };
+ double len = in.getDouble();
+ in.skipSpace();
+ for (Unit *p=units; p->name; p++)
+ if (in.check(p->name)) {
+ len *= p->factor;
+ break;
+ }
+ return len;
+}
+
+
+bool EmSpecialHandler::process (const char *prefix, istream &is, SpecialActions *actions) {
+ // em:moveto => move graphic cursor to dvi cursor
+ // em:lineto => draw line from graphic cursor to dvi cursor, move graphic cursor to dvi cursor
+ // em:linewidth <w> => set line width to <w>
+ // em:point <n>[,<x>[,<y>]] => defines point <n> as (<x>,<y>); if <x> and/or <y> is missing,
+ // the corresponding dvi cursor coordinate is inserted
+ // <x> and <y> are lengths
+ // em:line <n>[h|v|p], <m>[h|v|p] [,<w>] => draws line of width <w> from point #<n> to point #<m>
+ // point number suffixes:
+ // h: cut line horizontally
+ // v: cut line vertically
+ // p: cut line orthogonally to line direction (default)
+ // if <w> is omitted, the global line width is used
+ //
+ // supported length units: pt, pc, in, bp, cm, mm, dd, cc, sp
+ // default line width: 0.4pt
+
+ if (actions) {
+ _actions = actions; // save pointer to SpecialActions for later use in endPage
+ StreamInputBuffer ib(is, 128);
+ BufferInputReader in(ib);
+ string cmd = in.getWord();
+ if (cmd == "moveto")
+ _pos = DPair(actions->getX(), actions->getY());
+ else if (cmd == "lineto") {
+ DPair p(actions->getX(), actions->getY());
+ create_line(_pos, p, 'p', 'p', _linewidth, actions);
+ _pos = p;
+ }
+ else if (cmd == "linewidth")
+ _linewidth = read_length(in);
+ else if (cmd == "point") {
+ DPair p(actions->getX(), actions->getY());
+ int n = in.getInt();
+ if (in.getPunct() == ',') {
+ p.x(in.getDouble());
+ if (in.getPunct() == ',')
+ p.y(in.getDouble());
+ }
+ _points[n] = p;
+ }
+ else if (cmd == "line") {
+ int n1 = in.getInt();
+ int c1 = 'p';
+ if (isalpha(in.peek()))
+ c1 = in.get();
+ in.getPunct();
+ int n2 = in.getInt();
+ int c2 = 'p';
+ if (isalpha(in.peek()))
+ c2 = in.get();
+ double lw = _linewidth;
+ if (in.getPunct() == ',')
+ lw = read_length(in);
+ map<int,DPair>::iterator it1=_points.find(n1);
+ map<int,DPair>::iterator it2=_points.find(n2);
+ if (it1 != _points.end() && it2 != _points.end())
+ create_line(it1->second, it2->second, char(c1), char(c2), lw, actions);
+ else {
+ // Line endpoints havn't necessarily to be defined before
+ // a line definition. If a point wasn't defined yet we push the line
+ // in a wait list and process the lines at the end of the page.
+ _lines.push_back(Line(n1, n2, char(c1), char(c2), lw));
+ }
+ }
+ }
+ return true;
+}
+
+
+/** This method is called at the end of a DVI page. Here we have to draw all pending
+ * lines that are still in the line list. All line endpoints must be defined until here. */
+void EmSpecialHandler::dviEndPage () {
+ if (_actions) {
+ FORALL(_lines, list<Line>::iterator, it) {
+ map<int,DPair>::iterator pit1=_points.find(it->p1);
+ map<int,DPair>::iterator pit2=_points.find(it->p2);
+ if (pit1 != _points.end() && pit2 != _points.end())
+ create_line(pit1->second, pit2->second, it->c1, it->c2, it->width, _actions);
+ // all lines with still undefined points are ignored
+ }
+ }
+ // line and point definitions are local to a page
+ _lines.clear();
+ _points.clear();
+}
+
+
+const char** EmSpecialHandler::prefixes () const {
+ static const char *pfx[] = {"em:", 0};
+ return pfx;
+}
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