Split the shapes in different files and made them all QObjects with QProperties.

2026-04-27 01:40:38 +02:00 · 2016-01-21 16:18:19 -05:00
parent ba1af4b724
commit c656f8246a
17 changed files with 1232 additions and 962 deletions
--- a/Polygon.cpp
+++ b/Polygon.cpp
@@ -0,0 +1,111 @@
+/*
+ * Polygon.cpp
+ *
+ * (c) 2016 Sofian Audry -- info(@)sofianaudry(.)com
+ *
+ * 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 "Polygon.h"
+
+void Polygon::setVertex(int i, const QPointF& v)
+{
+  // Constrain vertex.
+  QPointF realV = v;
+  _constrainVertex(toPolygon(), i, realV);
+  // Really set the vertex.
+  _rawSetVertex(i, realV);
+}
+
+void Polygon::_constrainVertex(const QPolygonF& polygon, int i, QPointF& v)
+{
+  // Weird, but nothing to do.
+  if (polygon.size() <= 3)
+    return;
+
+  // Save previous position of vertex.
+  QPointF prevV = polygon.at(i);
+
+  // Look at the two adjunct segments to vertex i and see if they
+  // intersect with any non-adjacent segments.
+
+  // Construct the list of segments (with the new candidate vertex).
+  QVector<QLineF> segments = _getSegments(polygon);
+  int prev = wrapAround(i - 1, segments.size());
+  int next = wrapAround(i + 1, segments.size());
+  segments[prev] = QLineF(polygon.at(prev), v);
+  segments[i]    = QLineF(v, polygon.at(next));
+
+  // We now stretch segments a little bit to cope with approximation errors.
+  for (QVector<QLineF>::Iterator it = segments.begin(); it != segments.end(); ++it)
+  {
+    QLineF& seg = *it;
+    QPointF p1 = seg.p1();
+    QPointF p2 = seg.p2();
+    seg.setP1( p1 + (p1 - p2) * 0.35f);
+    seg.setP2( p2 + (p2 - p1) * 0.35f);
+  }
+
+  // For each adjunct segment.
+  for (int adj=0; adj<2; adj++)
+  {
+    int idx = wrapAround(i + adj - 1, segments.size());
+    for (int j=0; j<segments.size(); j++)
+    {
+      // If the segment to compare to is valid (ie. if it is not
+      // the segment itself nor an adjacent one) then check for
+      // intersection.
+      if (j != idx &&
+          j != wrapAround(idx-1, segments.size()) &&
+          j != wrapAround(idx+1, segments.size()))
+      {
+        QPointF intersection;
+        if (segments[idx].intersect(segments[j], &intersection) == QLineF::BoundedIntersection)
+        {
+          // Rearrange segments with new position at intersection point.
+          v = intersection;
+          segments[prev] = QLineF(polygon.at(prev), v);
+          segments[i]    = QLineF(v, polygon.at(next));
+        }
+      }
+    }
+  }
+}
+
+QVector<QLineF> Polygon::_getSegments() const
+{
+  return _getSegments(toPolygon());
+}
+
+QVector<QLineF> Polygon::_getSegments(const QPolygonF& polygon)
+{
+  QVector<QLineF> segments;
+  for (int i=0; i<polygon.size(); i++)
+    segments.push_back(QLineF(polygon.at(i), polygon.at( (i+1) % polygon.size() )));
+  return segments;
+}
+
+QPolygonF Polygon::toPolygon() const
+{
+  QPolygonF polygon;
+  for (QVector<QPointF>::const_iterator it = vertices.begin() ;
+      it != vertices.end(); ++it)
+  {
+    polygon.append(*it);
+  }
+  return polygon;
+}
+
+
+