# ReadPixel (x,y,[buffer])

# Parameters

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

# Description

Reads a color value from either the current buffer or the specified buffer.
The returned colour value is in the form of an integer that contains the alpha, red, green and blue values of the pixel.
You can use this command on a locked buffer for a slight speed-up. See LockBuffer.
Warning: this is a low level command with no error checking for out of range parameters, use with care.
See also: GetColor, ReadPixelFast.

# Example

; ReadPixel/WritePixel Example
; ----------------------------
Graphics 640,480,16
Print "Press a key to read color values (this may take a few seconds)"
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())
; Use ReadPixel to get all the color information of the screen
For y=0 To GraphicsHeight()
For x=0 To GraphicsWidth()
pix(x,y)=ReadPixel(x,y)
Next
Next
Cls
Locate 0,0
Print "Press a key to write pixels (this may takes a few seconds)"
Print "Once this has finished, you can then press a key to end the program"
WaitKey()
; Use WritePixel to redraw the screen using the color information we got earlier
For y=0 To GraphicsHeight()
For x=0 To GraphicsWidth()
WritePixel x,y,pix(x,GraphicsHeight()-y) ; get y array value in backwards order, to flip screen
Next
Next
WaitKey()

Index
Click here to view the latest version of this page online