Legacy Document

Inside Macintosh: Imaging With QuickDraw /

Chapter 3 - QuickDraw Drawing / QuickDraw Drawing Reference

Routines / Drawing Arcs and Wedges

EraseArc

To erase a wedge, use the EraseArc procedure.

PROCEDURE EraseArc (r:\xDDRect; startAngle,arcAngle: Integer);

r

The rectangle that defines an oval's boundaries.

startAngle

The angle indicating the start of the arc.

arcAngle

The angle indicating the arc's extent.

DESCRIPTION

Using the patCopy pattern mode, the EraseArc procedure draws a wedge of the oval bounded by the rectangle that you specify in the r parameter with the background pattern for the current graphics port. As in the FrameArc procedure described on page 3-68 and as illustrated in Figure 3-21, use the startAngle and arcAngle parameters to define the arc of the wedge.

This procedure leaves the location of the graphics pen unchanged.

SPECIAL CONSIDERATIONS

The EraseArc procedure may move or purge memory blocks in the application heap. Your application should not call this procedure at interrupt time.

SEE ALSO

The patCopy pattern mode is described in "Boolean Transfer Modes With 1-Bit Pixels" beginning on page 3-7.