# jumpTo engine
**URL:** https://forum.kirupa.com/t/jumpto-engine/182214
**Category:** Uncategorized
**Created:** [March 16, 2006, 9:35am UTC](https://forum.kirupa.com/t/jumpto-engine/182214 "2006-03-16T09:35:19Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@manga](https://forum.kirupa.com/u/manga)
#### Post date: [March 16, 2006, 9:35am UTC](https://forum.kirupa.com/t/jumpto-engine/182214/1 "2006-03-16T09:35:19Z")
hey all,
I wanna make a simple (as possible) jump engine that makes jumps with a curve and at the position of a ring Object \_y it jumps higer or lower…
take a look at a demo pic…
ps its a quick and dirty drawing :))
Cheers,
M
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### Author:  [@mathew\_er](https://forum.kirupa.com/u/mathew_er)
#### Post date: [March 18, 2006, 10:17pm UTC](https://forum.kirupa.com/t/jumpto-engine/182214/2 "2006-03-18T22:17:31Z")
So you want that fish tu jump trough a center of a ring, right?
No testing, no guarantee, but anyway here you go:
Lets look at this picture…
1. You choose random point, as a center of the circle.
2. Calculate radius
3. Find starting position
4. Move fish along its path
Now lets start implementing =)
1. Thats easy 😉
2. In Flash 8, you can just use point class
```auto
var circleCenter:Point = new Point(300, 100);
var randPoint:Point = new Point(200, 0);
var radius:Number = Point.distance(circleCenter, randPoint);
// without flash 8 Pythagorean theorem will do
circleCenter = [300,100];
randPoint = [200, 0];
a = circleCenter[0]-randPoint[0];
b = circleCenter[1]-randPoint[1];
radius = Math.sqrt(a*a + b*b)
```
1. Thats just… well, lets make it possible to jump from both directions
```auto
// flash 8 solution
var startPoint:Point = new Point();
startPoint.x = (circleCenter.x-randPoint.x > 0) ? randPoint.x+radius : randPoint.x-radius;
// non-flash 8
startPoint = (circleCenter[0]-randPoint[0] > 0) ? randPoint[0]+radius : randPoint[0]-radius;
```
1. Sorry, I dont have much time right now, but you should be able to figure the rest by yourself. Look at Sen’s tutorial about 3D here at kirupa… there is a section about trigonometry and about movement on a circle ([link](http://www.kirupa.com/developer/actionscript/trigonometry.htm)) Good luck. If you need something, ill be back later =)
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### Author:  [@manga](https://forum.kirupa.com/u/manga)
#### Post date: [March 19, 2006, 9:41am UTC](https://forum.kirupa.com/t/jumpto-engine/182214/3 "2006-03-19T09:41:43Z")
hm thanks but still need some help here…
now i have the starting point…ok… and now i try to move it but what is the angle… i calculate it…
i am also trying to make the fish from startposition the \_rotation=0 and i want it to be at the higest point… \_rotation= -90 so its rotating along…
i try to make it work…
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### Author:  [@manga](https://forum.kirupa.com/u/manga)
#### Post date: [March 20, 2006, 8:30am UTC](https://forum.kirupa.com/t/jumpto-engine/182214/4 "2006-03-20T08:30:19Z")
hm thanks but still need some help here…
now i have the starting point…ok… and now i try to move it but what is the angle… i calculate it…
i am also trying to make the fish from startposition the \_rotation=0 and i want it to be at the higest point… \_rotation= -90 so its rotating along…
i try to make it work…