Deepak T <[EMAIL PROTECTED]> writes:

> I am writing a 2D 16 bit color arcade game.
> I have certain sprites (explosions, glows) which are drawn against a
> black background, when I draw these against a different background the
> sprite's edges do not blend with the background and the sprite
> looks bad, I am not talking about anti-aliasing here, I am talking
> about reading rgb of source pixel and combining it with rgb of destination
> pixel to make it look natural (the way it has been drawn against black
> background).

Either you have a real alpha channel or you should use a technique called 
color-keying, which means you draw only the parts of the sprites that are 
not a special color (black in your case). 

You can also try load the sprites into Gimp and use ColorToAlpha to convert 
black to an alpha channel. You might need to do some editing afterwards if 
your images contained black in the drawing itself. Then you'd have sprites
with real alpha channel and could do real alpha blending.

In any case, you want to use DirectFB (http://www.directfb.org/) for
your arcade game. Believe me...

Salut, Sven
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