# Basic trig/geom question

**URL:** <https://forum.kirupa.com/t/basic-trig-geom-question/277335>\
**Category:** Uncategorized\
**Created:** [December 10, 2008, 10:14pm UTC](https://forum.kirupa.com/t/basic-trig-geom-question/277335 "2008-12-10T22:14:35Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![mleep](https://avatars.discourse-cdn.com/v4/letter/m/ea5d25/32.png) [@mleep](https://forum.kirupa.com/u/mleep)\
**Post date:** [December 10, 2008, 10:14pm UTC](https://forum.kirupa.com/t/basic-trig-geom-question/277335/1 "2008-12-10T22:14:35Z")

</div>

I’m trying to place a series of movieclips from my library on a circle ( a slightly tilted circle ).  
That said, I have the following code to add the objects but nothing shows up.

I’m probably over-thinking this with this code, anyhow putting traces on each step shows that after the

```auto
public function init( ):void {
	mainCircle = new circle();
	calculate( mainCircle );
	addChild( mainCircle );
}

public function calculate( mc:MovieClip ):void {

	var centerX:Number = stage.stageHeight / 2;
	var centerY:Number = stage.stageWidth / 2;
	var maxSpeed:Number = 200;
	var zscroll:Number = 0;
	var yscroll:Number = 70;
	var radius:Number = 300;
	var imageScale:Number = 75
	var focalLength:Number = 500;
	var initialFocal:Number = 500;

	trace ( "1 mc x:" + mc.x + " y: " + mc.y );

	// Calculate angle
	mc.angle += ( 400 - centerX ) / maxSpeed; // 400 can be any number?
	mc.angle %= 360;
	mc.angle = mc.angle < 0 ? (360) : ( mc.angle );

	// Calculate axis
	mc.xx = Math.cos( mc.angle*(Math.PI/180))*radius;
	mc.zz = centerY-Math.sin( mc.angle*(Math.PI/180))*radius;
	mc.yy = yscroll*Math.sin( mc.angle*(Math.PI/180))-50;

	trace ( "2 mc x:" + mc.x + " y: " + mc.y );

	// Set clip position
	var currPos = (initialFocal-zscroll*5) / ( focalLength + mc.zz );
	mc.x = mc.xx * currPos + centerX;
	mc.y = mc.yy * currPos + centerY;

	trace ( "3 mc x:" + mc.x + " y: " + mc.y );

	// Set clip scale
	mc.scaleX = mc.scaleY = currPos * imageScale - (mc.zz*12/radius);
}

```

I get the following output from the trace calls - - -  
[COLOR=“Blue”]1 mc x:0 y: 0  
2 mc x:0 y: 0  
3 mc x:-107374182.4 y: -107374182.4[/COLOR]