Hello

[Gala'Vi and Liss @ Mainframe Country]

All right,

here is the deal. GetRGBAPixelData takes an area of a screen and dumps the
pixel data of that area into a float array.

You call it with GetRGBAPixelData(x1, y1, x2, y2, mode).

x1,y1 and x2,y2 are the coordinates of the screen area's corners. Upper
left and lower right respectively. The mode variable should be set to
either 0 or 1 depending on what kind of Z-buffer rendering you want to
use: back-to-front or front-to-back. This controls the way the Alpha
transparency is figured out. The results of blending will be different if
you traverse the depth buffer front-to-back or back-to-front. Meaning the
closest object is rendered first or the farthest. The pixel data will thus
be different. If you don't have any transparent objects in your scene then
don't worry about that parameter too much. It should be set to 1 to use
front-to-back or to 0 to use back-to-front traversal.

Hope this helps.

Gala'Vi Pushkareva.
NCSA, UIUC 


//***********************************************
  -- There is always a way, 
        you just have to find it.
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On Sun, 15 Feb 1998, AHMED MAHMOUD wrote:

> Hello All,
> I have a question , How can I know the RGB pixel value of a pixel at
> specified location ??
> I found  a function called GetRGBAPixelData(int,....).But I don't understand
> its  parameters or arguments.
> Thank you.
> 
> 
> 
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