Feature Request - Grouping sprites to share the same transform point

[karimbeyrouti]

This is a question / issue I raised on stack overflow which I think could be a feature: http://stackoverflow.com/questions/34724279/grouping-three-sprite-to-share-the-same-transform-point

Looking at the Three API, I cannot see anything obvious that would help solve this. Hopefully this is something that would also help others: Being able to group sprites to share the same centre of rotation / transform. Maybe this could use the THREE.Group object to group the sprites ?

Thank you for all the lovely work on Three.JS so far.

[mrdoob]

Can you create a jsfiddle we can work with/study?

[karimbeyrouti]

Certainly: https://jsfiddle.net/karimbeyrouti/4qt6Ljgt/2/

A little info:
The JS Fiddle creates a rows of Sprites: bullet point + longer sprite for label.
You can toggle camera position by clicking on the output - or wait 1.5 seconds for camera to toggle.

The issue here: would be great if the red bullet points would stay aligned with their blue label. Maybe a good way of grouping their transform pivot would be to use a THREE.Group ( instead of Object3D ) ? .

[WestLangley]

@karimbeyrouti You are passing pixels units into your OrthographicCamera constructor. What are your world units? Why are you moving the camera?

[karimbeyrouti]

I am moving the camera, because our app animates the view from top down to isometric. Our world units are screen space pixels, or at least what is what I was aiming for ( and it seems to be working nicely ).

[WestLangley]

Our world units are screen space pixels

Hmmm... I haven't seen that before... http://stackoverflow.com/a/17567292/1461008

In any event, can you add OrbitControls to your example. I am trying to understand what the feature should be. Are your sprites in world-space, or in a planar HUD in front of the scene?

[karimbeyrouti]

The sprites are indeed in world space, in our app groups of sprites form part of node of in a graph. At the moment I have stopped using sprites in favour of planes, and am copying the Quaternion from the camera (which is a lot easier to manage). However it would have been optimal to use sprites and be able to group them so a number of these could share a pivot point / transform.