bug(viewer): Top and Bottom viewpoints cannot determine the view orientation for Top or Bottom views.

[jsdbroughton]

Prerequisites

• I read the contribution guidelines
• I checked the documentation and found no answer.
• I checked existing issues and found no similar issue.
• I checked the community forum for related discussions and found no answer.
• I'm reporting the issue to the correct repository (see also speckle-server, speckle-sharp, specklepy, speckle-docs, and others)

What package are you referring to?

Viewer

Describe the bug

Viewpoints are included with a commit as Objects.BuiltElements.View: Objects.BuiltElements.View3D. These are correctly found and displayed as additional views to the canonical views.

In most cases, these can be correctly replicated to the viewer, assuming that model geometry describes what should be up in the viewer and that the origin and target properties are sufficient to present the view to the user.

Sending viewpoints that are directly down (Top) or directly up (Bottom) where the only difference between origin and target is a different Z property leaves the orientation of the model in the viewer indeterminate. No account is taken by the viewer of the forwardDirection or the upDirection properties of the View3D class, even when these are set.

To Reproduce

1. Commit includes 2 View3D objects with matching origin and target properties. img width="646" alt="Screenshot_20230222_134529" src="https://user-images.githubusercontent.com/760691/220638800-a50799f8-a30c-4c0a-971d-3a5fa41257e4.png">
2. Each View3D has a different forwardDirection and upDirection vector.
3. Selecting these views in turn will have no difference when selected in the frontend. Or will display at undetermined rotations if looked at in separate browser sessions.

Expected behavior

The viewer should rotate the model to the orientation sent in the View3D

Proposed Solution (if any)

If a forward and up vector are included, the viewer should use these to determine view orientation where the forward direction vector is X:#, Y:#, Z:(-)1

Test commits

A - https://speckle.xyz/streams/7ce9010d71/commits/afda4ffdf8
B - https://speckle.xyz/streams/7ce9010d71/commits/acad1bd506