public Triangle getTriangle(float x, float z) {
        return geomap.getTriangleAtPoint(x, z, getWorldScale() , getWorldTranslation());
    }
Get the triangle of this geometry at the specified local coordinate.
@param x local to the terrain patch
@param z local to the terrain patch
@return the triangle in world coordinates, or null if the point does intersect this patch on the XZ axis
jme3-terrain/src/main/java/com/jme3/terrain/geomipmap/TerrainPatch.java