[Newbies] How to draw a single pixel with permanence?

Lawson English lenglish5 at cox.net
Thu Apr 29 11:15:06 UTC 2010

I'm trying to go back to beginnings with my own ManelBrot morph because 
I can quite grok how the one I have works.

Mostly because I still dont grok morphs.

Example: I'm trying to plot points on a morph using the drawOn message 

drawOn: aCanvas
    "Draws the receiver on the given canvas"    

    super drawOn: aCanvas.
    aCanvas  form  colorAt: 30 at 30 put: Color black.

BUT, with or without the evocation of super drawOn, I can't get the 
point to stay around. It only draws during a drag. What is the pattern 
for this. I've looked at much code and many tutorials but they all seem 
to gloss over this little detail, or at least my eye skips it every time 
I look at all the examples I can find.


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