Comment #3 on issue 181 by [email protected]: PNode.toImage is not
centered and can create cropped images for PNodes with non-integral (x,y)
bounds
http://code.google.com/p/piccolo2d/issues/detail?id=181
I isolated the problem and identified a potential solution. The problem was
being caused around line 2845 in PNode, where the node bounds is expanded
to integer dimensions for rendering to a buffered image. Only the width and
height should be rounded to integer, but the x and y are also being
rounded. This is problematic because (for the node defined in
TestPPathToImage) the node bounds are (x,y,w,h) = (-2.5,-2.5,105,105), so
this is rounded to (-3,-3,105,105), so instead of setting the pnode to
appear at the origin, it is off by (0.5,0.5). I tried solving this problem
by expanding only the (w,h) to be integer, and letting the (x,y) remain
floating. This yielded the correct behavior; see attached file
TestPPathToImage-fixed.png. Here's a minimal patch that resolves the
problem:
Index:
../../../../workingcopy/piccolo2d.java/core/src/main/java/org/piccolo2d/PNode.java
===================================================================
--- ../../../../workingcopy/piccolo2d.java/core/src/main/java/org/piccolo2d/PNode.java
(revision
1020)
+++ ../../../../workingcopy/piccolo2d.java/core/src/main/java/org/piccolo2d/PNode.java
(revision
)
@@ -2854,7 +2854,7 @@
g2.setClip(0, 0, imageWidth, imageHeight);
final PBounds nodeBounds = getFullBounds();
- nodeBounds.expandNearestIntegerDimensions();
+
nodeBounds.setSize(Math.ceil(nodeBounds.getWidth()),Math.ceil(nodeBounds.getHeight()));
final double nodeWidth = nodeBounds.getWidth();
final double nodeHeight = nodeBounds.getHeight();
I haven't tested the behavior outside of TestPPathToImage, and I'm not sure
how many incompatibilities this fix will cause in existing programs. For
instance, applications may be working around this problem currently, and
may obtain the wrong behavior after this is fixed in piccolo.
Attachments:
TestPPathToImage-fixed.png 1.7 KB
--
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