[Q] why is it slow to move complex morphs

Ned Konz ned at bike-nomad.com
Wed Apr 9 20:52:15 UTC 2003

On Wednesday 09 April 2003 01:45 pm, Martin Drautzburg wrote:
> Just for curiosity ...
> When you move the trashcan, this is a nice and smooth move. But
> when you move a complex morph this is quite bumpy.
> I once looked at the WarpBitBlt and it did pixel operations in no
> time. So I thought: it can't be the foreground pixel moves that use
> up the CPU it must be the background.
> But this isn't true either, because a plain rectangle moves faster
> than a complex morph of the same size.
> Why is this ?

Because the complex morph is being redrawn in its entirety several 
times a second.

The really clever way to do the drag code would be to hide the Morph, 
have it draw itself to a FormCanvas, then move that Form around until 
you drop it. At which time you'd destroy the Form, position the 
Morph, and unhide the Morph.

Ned Konz

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