Is there a way to draw on a client window and erase only the pen color
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I am programming a small drawing application. And what I do is rubber band a red circle and draw in black (eventually any color but red). And my program draws designs inside of the circle, and then when the user is done, the user can make a new circle. And I want the circle to erase itself and not the designs it may encounter in the rubber banding. I would like to know how to just erase the circle. This means I am asking a general mixed mode involving the SetROP2 function in the Windows GDI. Is there a way to draw on a client window and erase only the pen color? (Erase means make it white.)
Andrew Katz
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I am programming a small drawing application. And what I do is rubber band a red circle and draw in black (eventually any color but red). And my program draws designs inside of the circle, and then when the user is done, the user can make a new circle. And I want the circle to erase itself and not the designs it may encounter in the rubber banding. I would like to know how to just erase the circle. This means I am asking a general mixed mode involving the SetROP2 function in the Windows GDI. Is there a way to draw on a client window and erase only the pen color? (Erase means make it white.)
Andrew Katz
This has nothing to do with ROP, just draw the circle based on a Boolean flag and when the flag changes issue a command to redraw the area that contained the circle.
INTP "Program testing can be used to show the presence of bugs, but never to show their absence."Edsger Dijkstra