[Lazarus] Mac Drawing

[Felipe Monteiro de Carvalho]

I would do it like this:

1> Work with a bitmap canvas instead of the image canvas
2> Draw your image to the bitmap
3> Convert the bitmap to a TLazIntfImage
4> It should now be trivial to build an image inversion function, you
can just create a loop to read and change the pixels
5> Convert the TLazIntfImage back to the bitmap
6> Draw the bitmap in the image canvas

More info here:

http://wiki.lazarus.freepascal.org/Developing_with_Graphics#Working_with_TLazIntfImage

-- 
Felipe Monteiro de Carvalho