Drawing and removing lines on a canvas
Posted on 2001-08-20
I'm writing a small graphics editor and I need to know how to do fast removing of lines on a canvas. I have drawn a rectangles on the screen and want to move this rectangle on the canvas. First I remove the current rectangle and then redraw it somewhere else on the canvas. I can't get the removing of the rectangle to work. I've experimented with the Pen.Mode property a lot but didn't get it to work properly. I think I must use something like pmNot,pmXor or pmNotXor in combination with the color of the line and the background of the canvas. I do not want to redraw the entire canvas on the Paint event everytime I move a rectangle. Does anyone know what to do?