David Janik-Jones <[EMAIL PROTECTED]> wrote:
> Jeanne,
>
> A while ago I was trying to figure out how to move an object in a angle
> direction. You were kind enough to supply the following which works
> perfectly *EXCEPT* it seems to move the object on the specified angle
> *MINUS* 90 degrees.
>
> I've tried to add that back in by using a "+90" in my script as follows but
> am having no luck.
>
> Anyone?
Just a guess: In doing trig and graphics, one needs to consider the
periodicity of trig function values vs. angle. In evaluating an angle
computed with a trig function, you may have to consider which quadrant of
the xy axis system a point is in before using the angle returned by the trig
function for the angle of the ray between the point and the origin. For
example, the angle returned may be measured from the nearest arm of the
x-axis, not the right arm.
In response by a challenge Scott Rossi made a few months ago to the Metacard
list, I made up a stack, "fun sliders", in which I worked some of this out
(a slider can be dragged around an arbitrary ellipse or polygon). It isn't
bullet proof and may not directly solve David's problems, but I will email
it to him and submit it to Rev's user contribution site for the amusement of
others.
Rich Herz <[EMAIL PROTECTED]>
