def setColour():
    for idx, x in enumerate(range(0,900,100)):
        for idy, y in enumerate(range(0,900,100)):
            pass
    if idx+idy == patchSize-1:
        colourBox=colourList[1]
    elif idx+idy < patchSize-1:
        colourBox=colourList[0]
    elif idx+idy > patchSize-1:
        colourBox=colourList[2]