using namespace std;
using namespace ArdourCanvas;
-Line::Line (Group* parent)
- : Item (parent)
- , Outline (parent)
+Line::Line (Canvas* c)
+ : Item (c)
{
+}
+Line::Line (Item* parent)
+ : Item (parent)
+{
}
void
bbox.x1 = max (_points[0].x, _points[1].x);
bbox.y1 = max (_points[0].y, _points[1].y);
- bbox = bbox.expand (_outline_width / 2);
+ bbox = bbox.expand (0.5 + (_outline_width / 2));
_bounding_box = bbox;
_bounding_box_dirty = false;
Line::render (Rect const & /*area*/, Cairo::RefPtr<Cairo::Context> context) const
{
setup_outline_context (context);
- context->move_to (_points[0].x, _points[0].y);
- context->line_to (_points[1].x, _points[1].y);
+
+ Duple p0 = item_to_window (Duple (_points[0].x, _points[0].y));
+ Duple p1 = item_to_window (Duple (_points[1].x, _points[1].y));
+
+ if (_outline_width <= 1.0) {
+ /* See Cairo FAQ on single pixel lines to understand why we add 0.5
+ */
+
+ const Duple half_a_pixel (0.5, 0.5);
+ p0 = p0.translate (half_a_pixel);
+ p1 = p1.translate (half_a_pixel);
+ }
+
+ context->move_to (p0.x, p0.y);
+ context->line_to (p1.x, p1.y);
context->stroke ();
}
void
Line::set (Duple a, Duple b)
{
- begin_change ();
-
- _points[0] = a;
- _points[1] = b;
-
- _bounding_box_dirty = true;
- end_change ();
-
- DEBUG_TRACE (PBD::DEBUG::CanvasItemsDirtied, "canvas item dirty: line change\n");
+ if (a != _points[0] || b != _points[1]) {
+ begin_change ();
+
+ _points[0] = a;
+ _points[1] = b;
+
+ _bounding_box_dirty = true;
+ end_change ();
+ }
}
void
-Line::set_x0 (Coord x0)
+Line::set_x (Coord x0, Coord x1)
{
- begin_change ();
-
- _points[0].x = x0;
-
- _bounding_box_dirty = true;
- end_change ();
+ if (x0 != _points[0].x || x1 != _points[1].x) {
+ begin_change ();
+
+ _points[0].x = x0;
+ _points[1].x = x1;
+
+ _bounding_box_dirty = true;
+ end_change ();
+ }
+}
- DEBUG_TRACE (PBD::DEBUG::CanvasItemsDirtied, "canvas item dirty: line change\n");
+void
+Line::set_x0 (Coord x0)
+{
+ if (x0 != _points[0].x) {
+ begin_change ();
+
+ _points[0].x = x0;
+
+ _bounding_box_dirty = true;
+ end_change ();
+ }
}
void
Line::set_y0 (Coord y0)
{
- begin_change ();
-
- _points[0].y = y0;
-
- _bounding_box_dirty = true;
- end_change ();
+ if (y0 != _points[0].y) {
+ begin_change ();
+
+ _points[0].y = y0;
+
+ _bounding_box_dirty = true;
+ end_change ();
+ }
DEBUG_TRACE (PBD::DEBUG::CanvasItemsDirtied, "canvas item dirty: line change\n");
}
void
Line::set_x1 (Coord x1)
{
- begin_change ();
-
- _points[1].x = x1;
-
- _bounding_box_dirty = true;
- end_change ();
-
- DEBUG_TRACE (PBD::DEBUG::CanvasItemsDirtied, "canvas item dirty: line change\n");
+ if (x1 != _points[1].x) {
+ begin_change ();
+
+ _points[1].x = x1;
+
+ _bounding_box_dirty = true;
+ end_change ();
+ }
}
void
Line::set_y1 (Coord y1)
{
- begin_change ();
-
- _points[1].y = y1;
-
- _bounding_box_dirty = true;
- end_change ();
+ if (y1 != _points[1].y) {
+ begin_change ();
+
+ _points[1].y = y1;
+
+ _bounding_box_dirty = true;
+ end_change ();
+ }
+}
- DEBUG_TRACE (PBD::DEBUG::CanvasItemsDirtied, "canvas item dirty: line change\n");
+bool
+Line::covers (Duple const & point) const
+{
+ const Duple p = window_to_item (point);
+ static const Distance threshold = 2.0;
+
+ /* this quick check works for vertical and horizontal lines, which are
+ * common.
+ */
+
+ if (_points[0].x == _points[1].x) {
+ /* line is vertical, just check x coordinate */
+ return fabs (_points[0].x - p.x) <= threshold;
+ }
+
+ if (_points[0].y == _points[1].y) {
+ /* line is horizontal, just check y coordinate */
+ return fabs (_points[0].y - p.y) <= threshold;
+ }
+
+ Duple at;
+ double t;
+ Duple a (_points[0]);
+ Duple b (_points[1]);
+ const Rect visible (window_to_item (_canvas->visible_area()));
+
+ /*
+ Clamp the line endpoints to the visible area of the canvas. If we do
+ not do this, we have a line segment extending to COORD_MAX and our
+ math goes wrong.
+ */
+
+ a.x = min (a.x, visible.x1);
+ a.y = min (a.y, visible.y1);
+ b.x = min (b.x, visible.x1);
+ b.y = min (b.y, visible.y1);
+
+ double d = distance_to_segment_squared (p, a, b, t, at);
+
+ if (t < 0.0 || t > 1.0) {
+ return false;
+ }
+
+ if (d < threshold) {
+ return true;
+ }
+
+ return false;
}