white
Five commonly-used patterns are defined as Quickdraw globals; ie, they
exist at small negative offsets from A5. Quickdraw.h defines the external
variables:
white 0xFFFFFFF8 -8(A5) (#20 above)
black 0xFFFFFFF0 -16(A5) (#1 above)
gray 0xFFFFFFE8 -24(A5) (#4 above)
ltGray 0xFFFFFFE0 -32(A5) (#23 above)
dkGray 0xFFFFFFD8 -40(A5) (#3 above)
Beware of using these addresses in an interrupt handler or at any time in
which you can't be sure that A5 has been correctly set. See SetupA5.
See Pattern for a description of the layout of the bytes defining a pattern.