Hello

[Lisa Sobierajski Avila]

Hello,

Gala'Vi - your description was almost right - the last variable indicates
front buffer or back buffer, it has nothing to do with blending.
GetRGBAPixelData() does not render, it simply grabs values off the screen
(from the front (1) or back (0) buffer). 

Lisa

At 04:28 PM 6/21/99 -0500, Gala'Vi and Liss @ Mainframe Country wrote:
>
>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.
>              (B.Hambly "Children Of The Jedi")
>//***********************************************
>
>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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>
>
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