ChromiteBlue.com

a simple analog clock based on shapes.

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all the ActionScript is all contained in a single file: Clock.as
this is added into the movie with #include “Clock.as” on the frame level

if there is interest, I’ll rewrite this as an object, add a few more options, and improve the script a bit.

it can be made small

or large

Notes:
as this method uses a series of lines to construct the curve, a low angular change will result in a smoother curve. however, if a higher value is used, this will construct what appear to be “warped” polygons. for example, an angular change of 45 degrees (Pi/4 rad) will give an eight sided polygon. changing the dx and dy will still result in an elliptical shape.

ActionScript:

with( MovieClip_Object ) {

	//center of ellipse
	var x0 = Stage.width/2;
	var y0 = Stage.height/2;
	//ellipse bounds
	var dx = 300;
	var dy = 100;
	//angular change
	var dn = 1 * (Math.PI/180);

	var r,x,y;
	lineStyle(1, 0x000000);
	for( var n=0; n<2*Math.PI; n+=dn ) {
		x = dx*Math.cos(n);
		y = dy*Math.sin(n);
		moveTo(x0+x,y0+y);
		x = dx*Math.cos(n+dn);
		y = dy*Math.sin(n+dn);
		lineTo(x0+x,y0+y);
	}

}

angle conversion:

var angle_deg = angle_rad * 180/Math.PI;
var angle_rad = angle_deg * Math.PI/180;

find (x,y) from angle and radius:

var x = radius * cos( angle_rad );
var y = radius * sin( angle_rad );

a minor issue you will come across in ActionScript is that all of trigonometry functions in Math are based on the angle in radians, and a MovieClip’s _rotation property is based on the angle in degrees (this is not a bug or a flaw, but rather a design decision).

so a bit of simple algebra…

using a ratio:

angle_in_degrees/degrees_in_a_rotation = angle_in_radians/radians_in_a_rotation

one full rotation from origin to origin is 360 degrees or 2π radians:

plugged into the ratio:

angle_in_degrees/360 = angle_in_radians/2π

and solving for either variable:

angle_in_degrees/360 = angle_in_radians/2π
→
( angle_in_degrees/360 ) * 360 = ( angle_in_radians/2π ) * 360
→
angle_in_degrees = ( angle_in_radians * 360 ) /2π
→
angle_in_degrees = ( angle_in_radians * 180 ) /π
→
angle_in_degrees = angle_in_radians*180/π

and

angle_in_radians/2π = angle_in_degrees/360
→
( angle_in_radians/2π ) * 2π = ( angle_in_degrees/360 ) * 2π
→
angle_in_radians = ( angle_in_degrees/360 ) * 2π
→
angle_in_radians = ( angle_in_degrees/180 ) * π
→
angle_in_radians = angle_in_degrees*π/180