[wxPython-users] Re: Trouble with drawing, I need some ideas :)

[Christopher Barker]

Peter Damoc wrote:
> I was thinking that almost all drawing is done off-screen and that the 
> library that does the background drawing is the main reason for certain 
> performances issues.
> I didn't imagine that the final blitting to the pdc could be that 
> costly. :)

Have you tried anything yet?

All I know is that with the old DC method, a masked bitmap was 
apparently a non-native concept, so wx had to loop through all the 
pixels, check the mask, then draw or not draw the given pixel. It was 
orders of magnitude slower than drawing a non-masked bitmap. As a 
result, I didn't put multiple transparent layers in FloatCanvas -- you 
could draw a LOT of vector objects faster than drawing a masked bitmap.

I'm really curious how the performance is with alpha bitmaps with 
Graphics Context, but I don't know when I'll be able to test.

-Chris


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