Re: [pygame] Blitting to alpha channel or using another image's alpha channel

[Lenard Lindstrom <len-l@xxxxxxxxx>]

Lenard Lindstrom wrote:
> >  
> You can use the BLEND_RGBA_MIN flag with a surface blit. Make sure the 
> mask is all black and that all the target surface pixels have an alpha 
> of 255. Before that was available (Python 1.8.1?) there was the 
> surfarray module. surfarray.pixels_alpha lets one get at the alpha 
> plane of a surface and manipulate it with array operations. See the 
> shadowed effects in the Pygame cookbook for an example:
>
> http://www.pygame.org/wiki/ShadowEffects?parent=CookBook
>
> But you need either NumPy or Numeric for this to work.
The advice with the black mask is wrong. It needs to be white.

--
Lenard Lindstrom
<len-l@xxxxxxxxx>