# ReadPixelFast (x,y,[buffer])

# Parameters

x - y-coordinate of pixel y - y-coordinate of pixel buffer (optional) - name of buffer to read colour value from, e.g. BackBuffer()

# Description

Reads a color value from either the current buffer or the specified buffer, and returns it.
The returned colour value is in the form of an integer than contains the alpha, red, green and blue values of the pixel.
IMPORTANT:
You *must* use this command on a locked buffer, otherwise the command will fail. See LockBuffer.
Also, you must make sure that the coordinates that you are reading from are valid, otherwise you will end up reading garbage values.
WARNING:
By not following the above advice, you may cause your computer to crash.
See also: GetColor, ReadPixel.

# Example

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

Index
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