EgUseWatchEntityComponent.java

    public static nz.sodium.Cell<Axes3D> watchEntityAxes(
        nz.sodium.Cell<Option<EcsReadOnlySceneContext>> cSceneCtxOp,
        nz.sodium.Stream<EcsSceneChanges> sSceneChanges,
        int entityId
    ) {
        return nz.sodium.Cell.switchC(watchEntityComponentOp(cSceneCtxOp, sSceneChanges, entityId, Axes3DComponent.ecsComponent).lift(
            watchEntityComponentOp(cSceneCtxOp, sSceneChanges, entityId, ChildComponent.ecsComponent),
            (Option<Axes3DComponent> axesOp, Option<ChildComponent> parentOp) -> {
                Option<Integer> parentIdOp = parentOp.map(ChildComponent::parentId);
                Axes3D localAxes = axesOp.map(Axes3DComponent::axes3D).orSome(Axes3D.identity);
                if (parentIdOp.isNone()) {
                    return new sodium.Cell<>(localAxes);
                } else {
                    int parentId = parentIdOp.some();
                    return watchEntityAxes(cSceneCtxOp, sSceneChanges, parentId).map(
                        (Axes3D parentAxes) ->
                            parentAxes.fromThisSpace(localAxes)
                    );
                }
            }
        ));
    }