The mark is used to remember a colour index. The current colour. The special marker used in colour spectrum display prevents the user from seeing the colour of the current index, but it is visible. Starts Xloadct to allow selection of one of the predefined colour tables. Note that when you change the colour map via Xloadct, Xpalette is not always able to keep its display accurate.
Displays help text.
Completely redraws the display using the current state of the colour map. Exchanges the mark and the current index. The colours lying between the current index and the mark index are interpolated linearly to lie between the colours of two endpoints. Colour index 0 is at the upper left. The colour index increases monotonically by rows going left to right and top to bottom.