update method
dynamic
update()
Implementation
update() {
light.updateMatrixWorld(false);
double coneLength = light.distance ?? 1000;
var coneWidth = coneLength * Math.tan(light.angle!);
cone.scale.set(coneWidth, coneWidth, coneLength);
_SpotLightHelpervector.setFromMatrixPosition(
light.target!.matrixWorld);
cone.lookAt(_SpotLightHelpervector);
if (color != null) {
cone.material.color.copy(color);
} else {
cone.material.color.copy(light.color);
}
}