Re: [pygame] Masking Test: Simulated Lighting (Follow-Up)

[Kris Schnee <kschnee@xxxxxxxxxx>]

Kamilche wrote:
> Try the following code. It uses a gradient light.

I'm trying to figure out how your example (much better than mine) works. 
It looks like the key is the last line of this function:

> def RefreshNight(night, alpha, light, x, y):
>     a = NIGHTCOLOR[3]
>     alpha.fill([a, a, a])
>     r = LIGHTSIZE/2
>     alpha.blit(light, [x-r, y-r])
>     pygame.surfarray.pixels_alpha(night)[:, :] = 
> pygame.surfarray.pixels2d(alpha)

So, to get around the problem of a pre-drawn lightmask not getting 
properly put onto the dark mask, you're using the surfarray module to 
address the alpha channel of the dark mask directly? Is that how this 
works? I don't recognize the [:,:] syntax -- a list containing two 
copies of a list, maybe.

I tried using a version of that line instead of directly blitting my 
lightmask onto dark, but Python complained that it couldn't safely cast 
the array. I guess there's some trick to how the surfaces are defined, 
but I haven't been able to figure it out yet.

Kris