[SDL] How to set an individual pixel to transparent?

[matt hull]

i havent messed with transparent pixels before, but here is info from  
the wiki about the pixel format,

http://www.libsdl.org/cgi/docwiki.cgi/SDL_5fPixelFormat

you should use this to find what the rgb format is.  no need for  
#ifdef bigendian, if you have that.

i would guess you are trying to use the apha on the pixel ?

matt

On Sep 23, 2007, at 9:02 PM, David Bruce wrote:

> Hi,
>
> Quick question - if p points to an individual pixel in a 32-bit RGBA
> SDL_Surface, how do I set it to transparent for either a little- or
> big-endian system?
>
> (I'm trying to write a function to round off the corners of  
> rectangles, and I
> think I've figured the rest out, but I'm having trouble with the  
> actual
> manipulation of the pixel data).
>
> Thanks for any help,
> -- 
> David Bruce
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