BTW, I have jst seen this:
"
e.g. to check if a pixel is black, I did:
If colour AND $00111111 = $00000000
This eliminates the alpha value getting in the way - as it will always end up $00 after the operation.
"
But this not correct. A pixel could be of color $222222, and $222222 AND $111111 will also be $0, but nevertheless it is not black. So you need to use this instead:
if colour AND $00FFFFFF = $00000000
"
e.g. to check if a pixel is black, I did:
If colour AND $00111111 = $00000000
This eliminates the alpha value getting in the way - as it will always end up $00 after the operation.
"
But this not correct. A pixel could be of color $222222, and $222222 AND $111111 will also be $0, but nevertheless it is not black. So you need to use this instead:
if colour AND $00FFFFFF = $00000000