support dynamic trixls.

js/pixl/public/trixl.html

			return trixl.world.delete(key);
		}
		trixl.world.dynamic = [];
		trixl.dynamic = {};
		trixl.dynamic.orbit = function(pos, radius, color) {
			var color = color || trixl.color;
			return function(t) {
				var x = radius * Math.sin(t * 0.01),
				    y = radius * Math.cos(t * 0.01);
				return {x: pos[0] + x, y: pos[1] + y, z: pos[2], color: color};
			}
		}
		trixl.generate = {};
		trixl.generate.random = function(lo, hi, color) {
			var x = lo + Math.round(Math.random() * (hi - lo)),
		var angle = {x: 0, y: 0, z: 0};
		var offset = {x: 0, y: 0, z: 0};
		program.transform = gl.getUniformLocation(program, 'transform');
		trixl.redraw = function() {
		trixl.redraw = function(t) {
			var view = mat4.lookAt([], trixl.camera.pos, trixl.camera.focus, trixl.camera.up);
			var aspect = trixl.window.w / trixl.window.h;
				gl.drawArrays(gl.TRIANGLES, 0, 6 * 6);
			}
			trixl.world.dynamic.forEach(function(tr) {
				var tr = tr(t);
				gl.uniform4fv(program.color, tr.color);
				gl.uniformMatrix4fv(program.transform, false, transform([tr.x, tr.y, tr.z]));
				gl.drawArrays(gl.TRIANGLES, 0, 6 * 6);
			});
			gl.uniform4f(program.color, -1, -1, -1, 0);
			//angle.x += Math.PI / 10;
			//offset.z = Math.cos(angle.z * 0.1) * 2;
		}
		trixl.step = function() {
			trixl.redraw();
		trixl.step = function(t) {
			trixl.redraw(t);
			trixl.step.reqId = requestAnimationFrame(trixl.step);
		}
		trixl.start = function() {