On 14.06.2010, at 05:28, Chris Muller wrote:

> This is a little fix from Henry Johansen which, for me, improves the
> rendering of rotated Morphs with respect to translucency.  Today when
> Morphs are rotated they are always drawn with the Form paint rule, but
> Henriks change allows Form blend for 32-bit displays.
> 
> It seems to work, and improves the look of my applications.  You can
> see the difference easily by rotating a simple RectangleMorph that is
> alpha-colored..
> 
> However, as there are certainly more-qualified experts who may wish to
> comment on the subject first, I thought I would start it at the Inbox.
> 
> - Chris

Etoys depends on primary colors being preserved under rotation. It uses both rotation and color tests a lot.

When I rotate a sketch that had not had translucency before, it would have none after rotating. With your patch, its edges get fuzzy:

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So this solution is not general enough. If there was translucency before, it should be preserved under rotation, yes. But if there was none, it should not be introduced. I think there is a way to have your cake and eat it, too, though I'm not quite sure how atm.

- Bert -