Hi,
This patch implements better support for negative extents in the Arc2D
iterator. Before, we simply reversed the arc so that the extent would
always be positive; however this causes problems when the arc is apart
of a larger shape. Now, the iterator handles negative extents without
the reversing trick.
Cheers,
Francis
2006-12-05 Francis Kung <[EMAIL PROTECTED]>
* java/awt/BasicStroke.java
(capEnd): Prevent division by zero.
* java/awt/geom/Arc2D.java
(ArcIterator.ArcIterator): Do not shift the arc to make the extent
positive.
(ArcIterator.currentSegment): Handle a negative extent.
Index: java/awt/BasicStroke.java
===================================================================
RCS file: /cvsroot/classpath/classpath/java/awt/BasicStroke.java,v
retrieving revision 1.17
diff -u -r1.17 BasicStroke.java
--- java/awt/BasicStroke.java 4 Aug 2006 22:03:24 -0000 1.17
+++ java/awt/BasicStroke.java 5 Dec 2006 20:36:49 -0000
@@ -761,9 +761,13 @@
p1 = new double[]{a.last.P2.getX(), a.last.P2.getY()};
dx = p1[0] - p0[0];
dy = p1[1] - p0[1];
- l = Math.sqrt(dx * dx + dy * dy);
- dx = (2.0/3.0)*width*dx/l;
- dy = (2.0/3.0)*width*dy/l;
+ if (dx != 0 && dy != 0)
+ {
+ l = Math.sqrt(dx * dx + dy * dy);
+ dx = (2.0/3.0)*width*dx/l;
+ dy = (2.0/3.0)*width*dy/l;
+ }
+
c1 = new Point2D.Double(p1[0] + dx, p1[1] + dy);
c2 = new Point2D.Double(b.P1.getX() + dx, b.P1.getY() + dy);
a.add(new CubicSegment(a.last.P2, c1, c2, b.P1));
Index: java/awt/geom/Arc2D.java
===================================================================
RCS file: /cvsroot/classpath/classpath/java/awt/geom/Arc2D.java,v
retrieving revision 1.12
diff -u -r1.12 Arc2D.java
--- java/awt/geom/Arc2D.java 2 Jul 2005 20:32:29 -0000 1.12
+++ java/awt/geom/Arc2D.java 5 Dec 2006 20:36:49 -0000
@@ -774,14 +774,9 @@
y = a.getY();
w = a.getWidth();
h = a.getHeight();
- double start = a.getAngleStart() * (Math.PI / 180);
- double extent = a.getAngleExtent() * (Math.PI / 180);
+ double start = Math.toRadians(a.getAngleStart());
+ double extent = Math.toRadians(a.getAngleExtent());
- if (extent < 0)
- {
- extent = -extent;
- start = 2 * Math.PI - extent + start;
- }
this.start = start;
this.extent = extent;
@@ -790,11 +785,11 @@
limit = -1;
else if (extent == 0)
limit = type;
- else if (extent <= Math.PI / 2.0)
+ else if (Math.abs(extent) <= Math.PI / 2.0)
limit = type + 1;
- else if (extent <= Math.PI)
+ else if (Math.abs(extent) <= Math.PI)
limit = type + 2;
- else if (extent <= 3.0 * (Math.PI / 2.0))
+ else if (Math.abs(extent) <= 3.0 * (Math.PI / 2.0))
limit = type + 3;
else
limit = type + 4;
@@ -909,9 +904,20 @@
double kappa = (Math.sqrt(2.0) - 1.0) * (4.0 / 3.0);
double quad = (Math.PI / 2.0);
- double curr_begin = start + (current - 1) * quad;
- double curr_extent = Math.min((start + extent) - curr_begin, quad);
- double portion_of_a_quadrant = curr_extent / quad;
+ double curr_begin;
+ double curr_extent;
+ if (extent > 0)
+ {
+ curr_begin = start + (current - 1) * quad;
+ curr_extent = Math.min((start + extent) - curr_begin, quad);
+ }
+ else
+ {
+ curr_begin = start - (current - 1) * quad;
+ curr_extent = Math.max((start + extent) - curr_begin, -quad);
+ }
+
+ double portion_of_a_quadrant = Math.abs(curr_extent / quad);
double x0 = xmid + rx * Math.cos(curr_begin);
double y0 = ymid - ry * Math.sin(curr_begin);
@@ -932,7 +938,11 @@
// will *subtract* the y value of this control vector from our first
// point.
cvec[0] = 0;
- cvec[1] = len;
+ if (extent > 0)
+ cvec[1] = len;
+ else
+ cvec[1] = -len;
+
trans.scale(rx, ry);
trans.rotate(angle);
trans.transform(cvec, 0, cvec, 0, 1);
@@ -942,7 +952,11 @@
// control vector #2 would, ideally, be sticking out and to the
// right, in a first quadrant arc segment. again, subtraction of y.
cvec[0] = 0;
- cvec[1] = -len;
+ if (extent > 0)
+ cvec[1] = -len;
+ else
+ cvec[1] = len;
+
trans.rotate(curr_extent);
trans.transform(cvec, 0, cvec, 0, 1);
coords[2] = x1 + cvec[0];
