Rotating object to follow mouse

Question

Okay, say I have an object (a bee in this case) that I want
to follow the
mouse around, that part's easy:
property my,oldLoc
on beginSprite me
my = sprite(me.spriteNum)
oldLoc = my.loc
end
on exitFrame me
my.loc = the mouseLoc
if diff(my.locV,oldLoc.locV) + diff(my.locH,oldLoc.locH)
> 5 then
my.member = "BeeBuzz"
else my.member = "BeeStill"
oldLoc = my.loc
end
It even includes a cute little function to make the wings
buzz when it's
moving, and not when it's standing still. The tricky part is
I want to have
some way of making the bee rotate to move in the direction
the mouse moves.
This seems to *almost* work, except that when the locV
doesn't change, it
results in a divide-by-zero error:
my.rotation = atan((oldLoc.locH - my.locH) / (oldLoc.locV -
my.locV)) *
57.2958
I could check and artificially add a small amount to avoid
the
divide-by-zero, but that seems like a hash. Is there a better
way to do
this correctly?
(And does anybody mind if I rant a bit about how all rotation
properties in
the program operate in degrees, while all the trig functions
operate in
radians? And the program doesn't include a method to convert
between them
either. That's just annoying.)

Answer 1

Thanks. I generally try to avoid the Library behaviors
because I've found
that they mostly seem to be 98% unnecessary error-checking
and 2% functional
code, and it can often be very difficult to find and extract
that tiny
little bit of code that actually DOES anything. However, in
this case I was
able to pull a bit of useful code out of the Turn Towards
Mouse behavior -
extremely simplified of course. It didn't work at all out of
the box. For
the record, the code I used looks like this:
angle = GetAngle(oldLoc - my.loc) - 90
if my.rotation <> angle then my.rotation = angle
With the following code copied (mostly verbatim, but
simplified) from the
Turn Towards Mouse:
on GetAngle slope
deltaH = slope[1]
deltaV = slope[2]
if deltaH then
slope = float (deltaV) / deltaH
angle = atan (slope)
if deltaH < 0 then angle = angle + pi
else
if deltaV > 0 then angle = pi / 2
else if deltaV < 0 then angle = (3 * pi) / 2
else angle = 0
end if
return (angle * 180) / pi
end GetAngle
It seems to do pretty much what my original code did, only it
considers
those divide-by-zero situations separately as special cases.
Still seems
like more code than should be necessary to do what it does -
this feels like
the sort of thing that should be possible with 1-2 lines of
code, but
apparently it's not that simple...