## Rectangle on top of line…rotated at any angle

Just started a new game and i needed to have a character who could ‘walk’ on a line at any angle …even upside .

With a little trig it’s fairly easy to place a rectanguler movieclip on top of a line.

Here’s all the source code

Here’s the critical code

`c1 and c2 `

are the endpoints of the line that you can drag around (demo)

`hero`

is the name of my rectangular object

`xOffset `

is how far hero should move (based off left right arrow keys). Each time the key is pressed we add or subtract from this number. So it represents a “cumulative” and current x value.

`//calculate angle of line based on endpoints`

`var angle:Number = Math.atan2(c2.y - c1.y, c2.x - c1.x);`

`//rotation of MovieClips in Flash is in degrees...so convert`

`hero.rotation = angle * 180 / Math.PI;`

//how far (dx) are we from first of the two points

`var xFromOrigin:Number = xOffset - c1.x;`

`//just some trig here`

`var newY:Number = c1.y + xFromOrigin * Math.tan( angle);`

`//get new coordinates of hero`

```
````hero.x = xOffset + h * Math.sin(angle)`

`hero.y = newY - h * Math.cos(angle)`

```
```

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