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

[Lenard Lindstrom <len-l@xxxxxxxxx>]

Kris Schnee wrote:
> 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.
Numeric, and kin, support multidimensional arrays directly. Indices are 
comma separated in the get item operator. pixels_alpha() returns a 
two-dimensional array. For an m by n array, [:, :] is the same as [0:m, 
0:n], or for each row 0 to (n-1) of each column 0 to (m-1). An ellipsis, 
[...] , can also be used and is dimension independent.

--
Lenard Lindstrom
<len-l@xxxxxxxxx>