JS Sphere

sphere.js

var planePositions = [];
var r = 1;
	m = 3, // u segments
	n = 3, // v segments
	quads = [];
function getPlaneIndexes () {


	var buffer = [];
	var points = [],
		col = 0, row = 0;
	for(var i = 0, l = n * m; i < l; i++) {
		points[i] = {
			u: col,
			v: row
		};

		col++;
		if(col == m) {
			col = 0;
			row++;
		}
	}

	console.log("points: ", points);

	// create quads
	for(var i = 0, l = m * n; i < l; i++) {
		var point = points[i];
		//var offset = 1 + point.row;
		if(point.u < (m - 1) && point.v < (n - 1)) {
			console.log("get quad for point ", i);
			// draw triagles for quad using top left point as origin(i)
			// poin1 = i + 1, i, i + m --- OK
			// poin2 = i + 1, i + m, i + m + 1
			var triA = [i + 1, i, i + m];
			var triB = [i + 1, i + m, i + m + 1];
			var quad = [triA, triB];

			quads.push(quad);

			// triA
			buffer.push(quad[0][0]);
			buffer.push(quad[0][1]);
			buffer.push(quad[0][2]);
			// triB
			buffer.push(quad[1][0]);
			buffer.push(quad[1][1]);
			buffer.push(quad[1][2]);
		}

	}

	// console.log(quads);
	// console.log(buffer);

	return {
		quads: quads,
		points: points,
		buffer: buffer
	};
}

Math.radians = function(degrees) {
  return degrees * (Math.PI / 180);
};

Math.degrees = function(radians) {
  return radians * (180 / Math.PI);
};

function drawSphere(points) {

	var positionsBuffer = [];


	for(var v = 0; v < n; v++) {
		//row
		for(var u = 0; u < m; u++) {
			// column in row

			var alpha = (180 / (n - 1)) * v,
				alphaRadians = Math.radians(alpha),
				beta = (360 / (m)) * u,
				betaRadians = Math.radians(beta);

			var vec3 = [
				r * (Math.sin(alphaRadians) * Math.cos(betaRadians)), // x
				r * Math.cos(alphaRadians), // y
				r * (Math.sin(alphaRadians) * Math.sin(betaRadians)) // z
			];

			console.log(v, u, " - a:", alpha, "b:",beta, vec3);

			//point.position = vec3;
			positionsBuffer.push(vec3[0]);
			positionsBuffer.push(vec3[1]);
			positionsBuffer.push(vec3[2]);
		}

	}

	console.log("positions", positionsBuffer);

}

var planeInfo = getPlaneIndexes();

drawSphere(planeInfo.points);