Here is what I am trying to do: I have an image (which is usually of one colour e.g shades of red), and I also have plots that I am displaying on top of the image. Everytime I redraw the plots, the image also gets redisplayed, which is extremely annoying since it takes a while.
To avoid redisplaying the image, I tried using various erasemodes for the plots, and here are the results:
1) Using erasemode 'xor': the plots are always BLACK, no matter what colour I try to set them to.
2) Using erasemode 'background': whenever I try to display a smaller area of the image by changing the axis, using axis([...]), the plots are also drawn outside the axis area.
Can anyone suggest a way to display plots in any colour I want, without redisplaying the image, while confining the plots to inside the axis?