Four drawing modes may be specified in the RastPort.DrawMode field: JAM1 Whenever you execute a graphics drawing command, one color is jammed into the target drawing area. You use only the primary drawing pen color, and for each pixel drawn, you replace the color at that location with the FgPen color. JAM2 Whenever you execute a graphics drawing command, two colors are jammed into the target drawing area. This mode tells the system that the pattern variables (both line pattern and area pattern--see the next section) are to be used for the drawing. Wherever there is a 1 bit in the pattern variable, the FgPen color replaces the color of the pixel at the drawing position. Wherever there is a 0 bit in the pattern variable, the BgPen color is used. COMPLEMENT For each 1 bit in the pattern, the corresponding bit in the target area is complemented--that is, its state is reversed. As with all other drawing modes, the write mask can be used to protect specific bitplanes from being modified. Complement mode is often used for drawing and then erasing lines. INVERSVID This is the drawing mode used primarily for text. If the drawing mode is (JAM1 | INVERSVID), the text appears as a transparent letter surrounded by the FgPen color. If the drawing mode is (JAM2|INVERSVID), the text appears as in (JAM1|INVERSVID) except that the BgPen color is used to draw the text character itself. In this mode, the roles of FgPen and BgPen are effectively reversed. You set the drawing modes using the statement: SetDrMd(&rastPort, newmode); Set the newmode argument to one of the four drawing modes listed above.