User talk:Tordanik/Proposed features/Open 3D model repository links

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Height, width and length

About the tags height width and length: -karlos- (talk) 19:24, 30 June 2017 (UTC)

  • Are this tags to be meaned before and not after applaying direction=*?
  • The default unit is Meter and they are NOT scale faktors? The models proportions will change!
  • Should we also have scale tree factors?
  • Please at last one tag scale=* for all 3 dimentions and proporional size change

-karlos- (talk) 19:24, 30 June 2017 (UTC)

Hi, thank you for your interest in the model repository. I've split the question in two parts, hope you don't mind!
  • The width/height/length tags have the same semantics as they do normally (they need to, as using the linked model is optional for applications). So e.g. the width of a bench is relative to the bench's direction, it's not fixed to the global coordinate axes.
  • These are existing tags with a default unit of meters, so yes. And they are indeed not scale factors. If you're trying to use a model of a two-seater bench to represent a four-seater bench, then that will inevitably lead to distortions. I feel that this would be an error by the mapper who linked the wrong model, though.
  • I'm trying to avoid tags that only make sense in the context of the repository as much as possible, which is why I prefer values that have a meaning in the real world ("height" and so on instead of "scale"). But as I said, a model should only be linked if it matches the real-world object. If applying the model's real measurements would lead to noticable distortions, then the model should probably not be linked in the first place.
But this is just a draft, so I'm happy to discuss this if you disagree! --Tordanik 11:02, 1 July 2017 (UTC)

Ah, I didn't think of benches but uniq famous Buildings. And they should be stored, already proper aligned and don’t need this tags, may be except direction. -karlos- (talk) 17:30, 1 July 2017 (UTC)

I agree that unique objects, such as famous buildings, should already be properly aligned, scaled, and ideally also properly rotated in the model. These tags are indeed intended for generic objects. --Tordanik 21:10, 1 July 2017 (UTC)

Model replacing more than one building

Many times, a model replaces more than one building (i.E. the Atomium). The model tags may be placed to a well positions node. How to tag the replaced buildings without seein many models? -karlos- (talk) 19:24, 30 June 2017 (UTC)

Replacing multiple elements that are not in a hierarchy (i.e. not building parts of a building, members of a site relation, etc.) is hopefully a comparatively rare case. I'm not sure why the Atomium would be mapped as multiple buildings rather than a single building with parts, for example. But in the cases where that doesn't work, we probably need to use a relation. --Tordanik 11:02, 1 July 2017 (UTC)

Even building:part(s) are often not members of a relation. So the description of the tag “3d_model” should explicitly demand a relation in this case. -karlos- (talk) 17:30, 1 July 2017 (UTC)

You don't need a relation to find out which building:part(s) belong to a building, and therefore to avoid rendering them. Like with normal 3D buildings, want to avoid relations unless they are needed. --Tordanik 21:08, 1 July 2017 (UTC)