On 5 Nov 2008, at 11:30 am, Michael A. Crawford wrote:
By default, positive angle values assigned to a rotation animation
result in counter clockwise rotation. Is there a way to cause the
rotation to occur in the clock-wise direction, with positive
values? For example, consider a needle rotating in a compass. As
the needle rotates in a clockwise direction the value that the
needle points to increases (up until it wraps around, of course).
In mathematics, it is conventional that increasing angular values
imply counter-clockwise rotation, because a standard coordinate system
has its origin in the lower left corner, with the y axis extending
upwards from there.
Can't you just negate the angular value? Multiply it by -1 for example.
There's no convention that I know of that says that "east" has a
greater value than "north" - you might find that not insisting on that
will make life easier.
hth, Graham
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