Parent Nodes for Children

[Nobkins]

I am struggling with parent nodes.

I have a child object in my blueprint and I want the matrix that moves / rotates the child to be relative to a specific node on the main object rather than relative to 0,0,0 of the main object. I thought that is what the "Parent node name" setting did but I can;t get it to work.

My main object / IGS has a few nodes and no matter which node I specify as the "Parent node name" in my child it makes no difference and the transforms are applied based on the main object origin of 0,0,0.

Does anybody know how to use this feature?

Jim

[VictoryWorks]

I've not tried it but that would have been my assumption on how it works.
Is it possible that it only works with auto-rotated nodes? i.e. it's primarily designed for children attached to bogies.

[Nobkins]

Googling finds references to people using it for headlights. Something about associating the animated part of a headlight to a parent. Not sure what would be animated on a headlight. Maybe US loco flashing lights or something.

[VictoryWorks]

Just a thought, how are you naming the node in the blueprint? Just the naming part or the LOD order/distance as well?

[Nobkins]

Tried both. with the lod order + distance + node name and also tried the node name by itself.

So my full name is:
1_0050_node_catWireO2_a

but also tried
node_catWireO2_a

That particular node does not appear in game as it is used as the point which the wires on my OHE attach to. It works for the wires (so definitely is in game) and for those you specify just the name part (node_catWireO2_a).

I have managed to work around it for the moment just annoying as took me a day to work around it and if the parent child thing had worked it would have been much easier.

[VictoryWorks]

Does not appear? As it's an empty object, or uses an invisible texture?

Glad you found a workaround but would be good to get the bottom of this for future.

[Nobkins]

It is an invisible node. It is a single quad positioned where I want one of the OHE lofted wires to "snap" to during auto placement of OHE. It is assigned the "Invisible" shader so it does not actually show in game.

I have also tried using nodes that visible in game and they did not work either. I could probably do with creating some test objects to try with some very simple items rather than the quite complex one I have. Not found the time for that yet

[Caliban]

I've used it for a cab child blueprint - I borrowed the cab model from another piece of stock ( and made it tilt! ), the child was definitely attached to the body as a parent node; however I can't remember about the relative matrix offset, it's not terribly relevant for a vehicle given it's offsetting from 0 anyway...

Time for a series of coloured boxes, I guess.

[Nobkins]

Time for a series of coloured boxes, I guess.

Yeh I think so. Less of a priority for me now as I worked around the issue. I am sure I will need it in the future though.

[irishrailguy]

Hi Jim,

I recently got this working (totally unintentionally ) on my semaphore. You do indeed use Parent Node Name in the children section of the blueprint, your child object is set relative to the parent node specified by using the latter portion of the node's name, so for example:

My semaphore's arm needs to be a child of the body, and the body has the name "1_0500_body". So in the blueprint editor, under your child's entry (assuming you've set up the corresponding child blueprint properly), simply set the name of the parent node to be whatever comes after the LOD and range values, so in my case the parent is "body". If you preview that in the editor you'll then see that your child is now offset relative to the pivot of the parent.

But in my case this wasn't meant to happen, the arm was floating above the body. So what I would actually suggest to make things more accurate is to set the child's position relative to the parent in your 3D suite, before you export, which removes the need to specify a parent in the blueprint. Unless you really need to, setting up hierarchies like that in the Blueprint Editor is something I avoid, as the game has a nasty habit of messing with your matrix values when you close and re-open the editor. My semaphore arm was modeled in it's position in Max relative to the post, so all I had to do was hide the post and export the arm as the child .igs, then do the same for the post as the main .igs.

Hope that helps somewhat!

Kevin