Piechart.zip file contributed by Sebastian Barthelmess. Reviewed by component owner GSmedley. Review below.


I compared the files to the 3.2 release and found a few different fixes
in the patch.

1. Two changes to the gradient drawing calls in piepiece.lzx:
                addColorStop(0, '0xffffff');
changed to:
                addColorStop(0, 0xffffff);

This looks right since addColorStop() is supposed to take a number as
the second parameter. This will lighten up charts that use the default
gradients, but this probably won't be a problem since the default's
appeal is limited. This fix should also be made in datamarker.lzx line 82.

2. Changes to skip drawing wedges that are too small. in
renderOutlineWedge();

I made a test and was able to produce a chart with wedges that shot
across the canvas. Applying these changes fixes that, however it can
leave adjacent wedges with the same colour, so I believe it would be
better to detect small wedges at a higher level where colour adjustments
can be made. Might be OK as a temporary patch.

3. Changes to deal with changing datasets in piechart.lzx

Applying this change made the test charts stop drawing altogether
because it doesn't allow for charts with static datasets. This would
need more thought before being applied.