This looks amazingly like my test code, except I have three circles red, green, and blue overlapping in the usual way. However, your code produces exactly the same non-effect as mine.

Just in case you are seeing something different to me, I have uploaded a pixel grab png of your demo above as my homenode pic. Does it look different on your machine?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: Tk::Canvas and using stipples by BrowserUk
in thread Tk::Canvas and using stipples by BrowserUk

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