Re: various observations

[Ethan A M. <merritt@u.washington.edu>]

On Tuesday 09 May 2006 10:38 pm, Ethan A Merritt wrote:
> On Tuesday 09 May 2006 10:20 pm, Daniel Sebald wrote:
> > my version of the PNG library creats hollow points even when 
> > they land inside the plot.  (See plot.)   
> 
> Indeed. Mine too.
> I have no idea why, but the bug must be in libgd.

Heh. Actually, it's not a libgd bug.

The circle is filled using a "fill to border" command,
where the border color is the circle.
But if the center of the current circle happens to
already have that color, as for instance if there is
another overlapping filled circle there already,
then "fill to border" is a no-op.

I can think of several workarounds for this, but I'm not
sure what the cleanest is.  Maybe draw the circle first
in some junk color, fill to *that* border, and then
re-trace in the real color?


-- 
Ethan A Merritt
Biomolecular Structure Center
University of Washington, Seattle 98195-7742