Trig Math Brainfart...

[ColbyCheeze]

Okay I have a rotation and an offset from (0,0). What is the formula for finding the (x,y)?

For instance a point is at (20,20), and if the world is rotated 45 degrees...where is the point at now?

[alillm]

Well the distance to your original point is

var dist = Math.sqrt(20*20+20*20);

and you know the rotation, 45 degrees which needs to be converted into radians.

var rot = 45;
var rads = rot*(Math.PI/180);

so now we can get the new position using basic trig.

var x = Math.cos(rads)*dist;
var y = Math.sin(rads)*dist;

Hope that helps.

Ali

[ColbyCheeze]

That would only work if the Y offset was at 0.

[alillm]

Not to contradict you but I'm fairly sure it works.

Ali

[ColbyCheeze]

n/m I figured it out...this works

box.rotation += 5;
var cos:Number = Math.cos( box.rotation * (Math.PI / 180));
var sin:Number = Math.sin( box.rotation * (Math.PI / 180));
var x1:Number = cos * offset - sin * offset;
var y1:Number = cos * offset + sin * offset;
box.x = x1 + boxX;
box.y = y1 + boxY;

[Pazil]

alillim's solution works, except you need to do:

var orig:Number = Math.atan2( 20, 20);

And then after you get his rads, do:

rads = rads + orig;

And then cosine/sine it to get the coordinates.


P.

[alillm]

That's assuming the position of the point is the origin rotation though, I was assuming that was just a point and we were rotating the whole "stage" 45 degrees. But yea, if that's what was meant then you just add on the original rotation.

Ali