: Item (parent)
, PolyItem (parent)
, Fill (parent)
+ , multiple (0)
+ , constant (0)
+ , cached_size (0)
{
}
+Polygon::~Polygon ()
+{
+ delete [] multiple;
+ delete [] constant;
+}
+
void
Polygon::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
{
render_path (area, context);
if (!_points.empty ()) {
- context->move_to (_points.front().x, _points.front().y);
+ /* close path */
+ Duple p = item_to_window (Duple (_points.front().x, _points.front().y));
+ context->move_to (p.x, p.y);
}
context->stroke_preserve ();
}
}
+void
+Polygon::cache_shape_computation () const
+{
+ Points::size_type npoints = _points.size();
+
+ if (npoints == 0) {
+ return;
+ }
+
+ Points::size_type i;
+ Points::size_type j = npoints -1;
+
+ if (cached_size < npoints) {
+ cached_size = npoints;
+ delete [] multiple;
+ multiple = new float[cached_size];
+ delete [] constant;
+ constant = new float[cached_size];
+ }
+
+ for (i = 0; i < npoints; i++) {
+ if (_points[j].y == _points[i].y) {
+ constant[i] = _points[i].x;
+ multiple[i] = 0;
+ } else {
+ constant[i] = _points[i].x-(_points[i].y*_points[j].x)/(_points[j].y-_points[i].y)+(_points[i].y*_points[i].x)/(_points[j].y-_points[i].y);
+ multiple[i] = (_points[j].x-_points[i].x)/(_points[j].y-_points[i].y);
+ }
+
+ j = i;
+ }
+}
+
+bool
+Polygon::covers (Duple const & point) const
+{
+ Duple p = canvas_to_item (point);
+
+ Points::size_type npoints = _points.size();
+
+ if (npoints == 0) {
+ return false;
+ }
+
+ Points::size_type i;
+ Points::size_type j = npoints -1;
+ bool oddNodes = false;
+
+ if (_bounding_box_dirty) {
+ compute_bounding_box ();
+ }
+
+ for (i = 0; i < npoints; i++) {
+ if (((_points[i].y < p.y && _points[j].y >= p.y) || (_points[j].y < p.y && _points[i].y >= p.y))) {
+ oddNodes ^= (p.y * multiple[i] + constant[i] < p.x);
+ }
+ j = i;
+ }
+
+ return oddNodes;
+}
+
+void
+Polygon::compute_bounding_box () const
+{
+ PolyItem::compute_bounding_box ();
+ cache_shape_computation ();
+}
+