How can I create a WebGL mesh from a JSON string in gwt-g3d?

How can I create a mesh (instance of StaticMesh) from a JSON string in gwt-g3d (http开发者_如何转开发://code.google.com/p/gwt-g3d/)?

If the JSON string is static, you can load it as an ExternalMeshResource (see http://code.google.com/p/gwt-g3d/source/browse/trunk/gwt-g3d-test/src/gwt/g3d/test/client/Lesson14Demo.java on how to use this resource).

If not, you can use JSONParser.parse(jsonString) to get a JSON value object, then do something like

Float32Array.create(jsonObj.get(fieldName).isArray().getJavaScriptObject().<JsArrayNumber>cast());

to gets a TypeArray that you can pass to StaticMesh. The fieldName above depends on your json string object. For example, if you json looks something like:

{
  "vertexPositions" : [0, 1, 2, ...]
  "vertexNormals" : [0, 1, 0, ...]
  "indices" : [0, 1, 2, ...]
}

then your fieldName can be "vertexPositions", "vertexNormals", and "indices". (Note that the indices array is usually of type Uint16Array instead of Float32Array). See the implementation of AbstractMeshResource for more information