I know how to make a circle and standard ellipse. example:

Object.x = center.X+cos(time*300)*200

Object.y = center.Y+sin(time*300)*300

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https://docs.google.com/file/d/0B-6JjcHcczubZGc1RGtDbF9Dbnc/edit?usp=sharing

That should link to a capx demonstrating. t is the step, or speed, theta is angle of rotation, a is one axis of the ellipse, b is the other

The initial transformation I posted rotates about the origin, so this new one is corrected for that.

The parametric equation is:

X(t) = Xc + a * cos(t) * cos(theta) - b * sin(t) * sin(theta)

Y(t) = Yc + a * cos(t) * sin(theta) + b *sin(t) * cos(theta)

AND OMG I NEED TO REFRESH MY TRIG. Thanks for pointing out a glaring weakness of mine. :(cincipon 2013-03-06 18:59:48

That should link to a capx demonstrating. t is the step, or speed, theta is angle of rotation, a is one axis of the ellipse, b is the other

The initial transformation I posted rotates about the origin, so this new one is corrected for that.

The parametric equation is:

X(t) = Xc + a * cos(t) * cos(theta) - b * sin(t) * sin(theta)

Y(t) = Yc + a * cos(t) * sin(theta) + b *sin(t) * cos(theta)

AND OMG I NEED TO REFRESH MY TRIG. Thanks for pointing out a glaring weakness of mine. :(

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@cincipon - would you happen to be able to post a working example like you did before? That link leads to a file that has nothing to do with this question.

Is there anywhere on the web you could point me to where I could learn about more 'gamey' maths stuff like this? I know that I might be able to just copy and paste and fiddle to get it working, but I'd rather really understand the maths behind it!

Cheers.Psynaptik 2014-02-09 17:29:56

Is there anywhere on the web you could point me to where I could learn about more 'gamey' maths stuff like this? I know that I might be able to just copy and paste and fiddle to get it working, but I'd rather really understand the maths behind it!

Cheers.

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