public void setLightMode(LightMode lightMode) {
        this.lightMode = lightMode;
        //if light space is not specified we set it to Legacy
        if (lightSpace == null) {
            if (lightMode== LightMode.MultiPass) {
                lightSpace = LightSpace.Legacy;
            } else {
                lightSpace = LightSpace.World;
            }
        }
    }
Set the light mode

@param lightMode the light mode

@see LightMode
jme3-core/src/main/java/com/jme3/material/TechniqueDef.java