Polygon fill algo?

Richard Gaskin ambassador at fourthworld.com
Sun Feb 14 18:12:35 EST 2021

Thanks, Monte. I checked it out, but unfortunately none of the options 
handle my specific use case in the way I want (which is arguably an 
unrealistic expectation, given that I need to have the fill region paint 
over some vertices).

I also discovered what may be a bug, or at least a curiosity: after 
playing with the nonzero and evenodd options, I tried to restore the 
default with:

   set the fillrule of the selobj to none

And got:

    Message execution error:
    Error description: Property: invalid enumeration value

Apparently "none" must be quoted.  Has it always been that way?  I've 
seen a couple other cases in recent years where keywords I could have 
sworn I'd used unquoted now throw errors until I quote them.

What rule can help us know when keywords must be quoted?

It also occurs to me: if there's no hint, adding "Hint:" looks like a 
bug, even though it may not be (doesn't seem to be in this case). Maybe 
I'll see if I can get some time to patch that...

Richard Gaskin
Fourth World Systems

Monte Goulding wrote:
 > Hi Richard
 > Have you checked out the `fillRule` property docs?
 > Cheers
 > Monte
 >> On 15 Feb 2021, at 9:25 am, Richard Gaskin via use-livecode 
<use-livecode at lists.runrev.com> wrote:
 >> I was hoping to use a single polygon draw a box, using the old trick 
of making discontiguous regions by adding a blank line between lists of 
 >> The results draws the lines as I expected, but the fill is 
unpredictable, at least for me.  Apparently the fill rules for a polygon 
cause it to not fill some regions, even when discontiguous.
 >> I guess I'll have to use separate objects, but I was wondering if 
anyone has a description of the polyfill rule(s), or better, a way to 
coerce discontiguous polygon regions to always be filled.
 >> --
 >> Richard Gaskin
 >> Fourth World Systems

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