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<h1>ReadPixelFast (x,y,[buffer])</h1>
<h1>Parameters</h1>
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x - y-coordinate of pixel
<br />
y - y-coordinate of pixel
<br />
buffer (optional) - name of buffer to read colour value from, e.g. BackBuffer() 
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<h1>Description</h1>
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Reads a color value from either the current buffer or the specified buffer,  and returns it.

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The returned colour value is in the form of an integer than  contains the alpha, red, green and blue values of the pixel. 

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IMPORTANT: 

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You *must* use this command on a locked buffer, otherwise the command will  fail. See LockBuffer. 

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Also, you must make sure that the coordinates that you are reading from are  valid, otherwise you will end up reading garbage values. 

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WARNING: 

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By not following the above advice, you may cause your computer to crash. 

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See also: GetColor, ReadPixel.  
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<h1><a href=../2d_examples/ReadPixelFast.bb>Example</a></h1>
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; ReadPixelFast/WritePixeFast Example
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; -----------------------------------
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Graphics 640,480,16
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Print "Press a key to read color values"
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WaitKey()
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; Load and draw an image on to the screen - can be anything
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pic=LoadImage("media/blitz_pic.bmp")
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DrawImage pic,0,0 
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; Initialise an array big enough to fit all the color information of the screen
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Dim pix(GraphicsWidth(),GraphicsHeight())
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; Lock buffer before using ReadPixelFast
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LockBuffer
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; Use ReadPixel to get all the color information of the screen
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For y=0 To GraphicsHeight()
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For x=0 To GraphicsWidth()
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pix(x,y)=ReadPixelFast(x,y)
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Next
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Next
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; Lock buffer after using ReadPixelFast
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UnlockBuffer
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Cls
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Locate 0,0
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Print "Press a key to write pixels"
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Print "Once this has finished, you can then press a key to end the program"
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WaitKey()
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; Lock buffer before using WritePixelFast
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LockBuffer
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; Use WritePixel to redraw the screen using the color information we got earlier
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For y=0 To GraphicsHeight()
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For x=0 To GraphicsWidth()
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WritePixelFast x,y,pix(x,GraphicsHeight()-y) ; get y array value in backwards  order, to flip screen
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Next
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Next
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; Unlock buffer after using WritePixelFast
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UnlockBuffer
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WaitKey()
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