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- #include "timing.h"
-
- #define gap 4 /* difference between one radius and the next */
- #define CorrectTime 2
- #define theWindowHeight (boundsRect.bottom-boundsRect.top)
- #define theWindowWidth (boundsRect.right-boundsRect.left)
-
- pascal short CircleOut(GrafPtr sourceGrafPtr, GrafPtr destGrafPtr, Rect boundsRect);
-
- /* Make a circular region and use it as the mask in CopyBits. Lots of overlap,
- but masked by timing correction. If you want to optimize it, look at the
- donut region code in "Circle in.c" */
-
- pascal short CircleOut(GrafPtr sourceGrafPtr, GrafPtr destGrafPtr, Rect boundsRect)
- {
- Rect theRect;
- short cx, cy;
- RgnHandle curregion;
- Point zeroPoint;
-
- zeroPoint.h=boundsRect.left;
- zeroPoint.v=boundsRect.top;
-
- cx = theWindowWidth / 2;
- cy = theWindowHeight / 2;
-
- theRect.left=cx-gap; /* circumscribing rectangle for circle */
- theRect.right=cx+gap;
- theRect.top=cy-gap;
- theRect.bottom=cy+gap;
- OffsetRect(&theRect, boundsRect.left, boundsRect.top);
-
- curregion=NewRgn();
-
- do
- {
- StartTiming();
- SetEmptyRgn(curregion);
- OpenRgn();
- FrameOval(&theRect); /* the circle region */
- CloseRgn(curregion);
- CopyBits(&(sourceGrafPtr->portBits), &(destGrafPtr->portBits),
- &boundsRect, &boundsRect, 0, curregion);
- theRect.left-=gap; /* make the rect bigger (and thus the circle) */
- theRect.right+=gap;
- theRect.top-=gap;
- theRect.bottom+=gap;
- TimeCorrection(CorrectTime);
- }
- while (!PtInRgn(zeroPoint, curregion));
-
- DisposeRgn(curregion);
-
- return 0;
- }
-