A Photoshop script to automate drawing evenly-spaced spokes. Written in JavaScript.

spokes.jsx

// use pixels for ruler units
var defaultRulerUnits = preferences.rulerUnits
preferences.rulerUnits = Units.PIXELS;

// get desired inputs from user
var spokeRadius		= Number(prompt("Spoke radius (in pixels)?", 100));
var colorCode		= parseInt("0x" + prompt("Stroke color (in hex, rrggbb)?", "a0a0a0"));
var strokeWidth		= Number(prompt("Stroke width?", 2));
var nPoints		= Number(prompt("How many spokes to draw?", 20));

// create a new document with request size
var canvasSize = spokeRadius * 2;
if(strokeWidth % 2 == 1)
	canvasSize += 1;
var docRef     = app.documents.add(canvasSize, canvasSize, 72.0, "Wheel spoke", NewDocumentMode.RGB, DocumentFill.TRANSPARENT);

// set color with provided color code
var fillColor = new SolidColor;
fillColor.rgb.red   = Math.floor(colorCode / 65536);
fillColor.rgb.green = Math.floor((colorCode % 65536) / 256);
fillColor.rgb.blue  = Math.floor(colorCode % 256);

// create the first top-to-down "line" as original to copy from
var left   = (canvasSize * 0.5) - (strokeWidth * 0.5);
var right  = left + strokeWidth;
var top    = 0;
var bottom = canvasSize * 0.5;
var bounds    = [ [left, top],[right, top],[right, bottom],[left, bottom] ];

// use "fill" to draw a line
docRef.selection.select(bounds, SelectionType.REPLACE, 0, false);
docRef.selection.fill(fillColor);

// repeatedly duplicate layer (copy line), then rotate by delta degrees
var delta  = 360.0 / nPoints;
var nIterations = nPoints - 1;
var layerIndex = 1;
var currentLayer = docRef.layers[0];

// first create duplicate layers
for(i=0; i<nPoints-1; i++)
	docRef.layers[0].duplicate();

// rotate each of the duplicated layers
for(i=1; i<nPoints; i++)
{
	currentLayer = docRef.layers[i];
	var degree = 360.0 * (i / nPoints);
	docRef.selection.selectAll();
	currentLayer.rotate(degree);
}

// clear selection and merge all visible layers into one
docRef.selection.deselect();
if(nPoints >= 1)
	docRef.mergeVisibleLayers();

// set units preference to original state
preferences.rulerUnits = defaultRulerUnits