Re: [GtkGLExt] glDrawPixels

[Philipp Klaus Krause <pkk spth de>]

Chris Le Sueur schrieb:
> OK, I found out that the get_pixels() are UNSIGNED BYTES in RGBA format.
> However, there's now another problem :)
> 
> Even though it specifies RGBA, Alpha data that I put into the pixbuf is
> ignored. I can test this by reading the get_pixels_array() output - if
> it is filled with [255 0 255 0] then it still renders a rectangle of
> pink.
> I'm not sure whether this is down to get_pixels() or DrawPixels(), hence
> I've asked on the list, not on IRC.
> 
> Do you have any idea what might be happening, and how to fix it?
> 

I think this is the expected behaviour for DrawPixles(): It will write
the pixels into the framebuffer as you specify them. (255, 0, 255, 0)
will be written as (255,0, 255, 0).
You will have to specify another blending equation if you want different
behaviour.

Philipp