Creating Circle Polygons

Relevant Cesium Source

Relevant Google Earth Source (link)

function makeCircle(radius, x, y) {
                        var center = ge.getView().copyAsLookAt(ge.ALTITUDE_RELATIVE_TO_GROUND);

var ring = ge.createLinearRing('');
                        var steps = 25;
                        var pi2 = Math.PI * 2;
                        for (var i = 0; i < steps; i++) {
                            var lat = center.getLatitude() + x + radius * Math.cos(i / steps * pi2);
                            var lng = center.getLongitude() + y + radius * Math.sin(i / steps * pi2);
                            ring.getCoordinates().pushLatLngAlt(lat, lng, 0);
                        }
                        return ring;
                    }

var polygonPlacemark = ge.createPlacemark('');
                    polygonPlacemark.setGeometry(ge.createPolygon(''));
                    var outer = ge.createLinearRing('');
                    polygonPlacemark.getGeometry().setOuterBoundary(makeCircle(.05, 0, 0));
                    ge.getFeatures().appendChild(polygonPlacemark);