Hugh,
You'll love the atan2 function. It takes care of all nasty bits at 90 and 270
degrees as well as dealing with the quadrants issues.
Use atan2(y,x) for angles measure clockwise from the x-axis
Use atan2(-y,x) for angles measure counterclockwise from the x-axis.
Jim Hurley
--| Get the point's relative coordinates...
put pointX - objX into x
put pointY - objY into y
if y=0 then
--| Handle the exceptions...
if x>0 then put 0 into tAngle
else put 180 into tAngle
else
put atan ((x*H)/(y*W)) into tAngle
--| Convert from radians to degrees...
put (tAngle * 180 / pi) into tAngle
--| Adjust the angle according to the quadrant...
put (tAngle MOD 180)+90 into tAngle
if y>0 then add 180 to tAngle
end if
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