Incorrect result for horizontal line search

[WinsenRC]

Hi,
Thanks for this awesome library, with lots of cool features.

I found the search result for horizontal line is empty, might because it got a special bound box which height value is 0. Thus the RectangleUtil.outcode() always return OUT_TOP | OUT_BOTTOM.

Here's my test code:

 
RTree rtree = RTree.star().create();
Line simLine = Geometries.line(40.0d, -20.0d, 45.0d, -40.0d);
rtree = rtree.add(1, simLine);
Line segLine = Geometries.line(35.0d, -25.0d, 45.0d, -25.0d);
List> result = rtree.search(segLine)
            .toList()
            .toBlocking()
            .single();

[davidmoten]

That's interesting! The code for this is copied from java.awt.geom.Rectangle2D.Double and I notice that this fails too:

Rectangle2D.Double r = new Rectangle2D.Double(35.0d, -25.0d, 45.0d, -25.0d);
assertTrue(r.intersectsLine(40.0d, -20.0d, 45.0d, -40.0d));

Perhaps you've stumbled across a JDK bug?

[WinsenRC]

I found some information from JDK API doc.

https://docs.oracle.com/javase/8/docs/api/java/awt/Rectangle.html

A Rectangle whose width or height is exactly zero has location along those axes with zero dimension, but is otherwise considered empty. The isEmpty() method will return true for such a Rectangle. Methods which test if an empty Rectangle contains or intersects a point or rectangle will always return false if either dimension is zero. Methods which combine such a Rectangle with a point or rectangle will include the location of the Rectangle on that axis in the result as if the add(Point) method were being called.

If a bound box has either zero-width or zero-height, the Java 2D would treat it as non-existence, thus any logical test gets failed on it. This behaviours might not be what we expected.

[davidmoten]

Righto, thanks for finding that doc. I guess we are going to need some new code. Perhaps we just use rectangle.intersectsLine || line.intersectsLine as the test with Java 2d code?

[davidmoten]

Fixed by #92