I have added a primitive to scene(looks like part of ellipsoidoutline), and I can rotate it around z-axis by using Matrix3.fromRotationZ. Now I want to rotate it around center point up and down with the border-top(border-bottom) parallel to xy plane, what should I do?
The following code is the modelMatrix used to rotate it around z-axis:
var rotMatrix = new Cesium.Matrix3.fromRotationZ(heading);
var modelMatrix = Cesium.Matrix4.multiply(
Cesium.Matrix4.fromRotationTranslation(rotMatrix, new Cesium.Cartesian3(0.0, 0.0, 0.0)),