Point Cloud Attenuation in ModelExperimental

[ptrgags]

In #9978, I added a transcoder from .pnts -> ModelExperimental. However, there are more point-cloud specific features to add, point cloud attenuation being the main one that's missing.

Point Cloud Shading Sandcastle + Model Experimental -- mostly working.

The nice thing is eye dome lighting seems to be working for free.

To Do:

• Now that Adds dynamic model/node transformations to ModelExperimentalNode #9989 is merged, I can finish the one TODO in the code about the baseResolution estimate.
• PointCloud3DTileContent has more handling code for maximumAttenutation, I need to find a place for this code.
• Update unit tests as needed.

[cesium-concierge]

Thanks for the pull request @ptrgags!

• ✔️ Signed CLA found.
• ❔ CHANGES.md was not updated.
  • If this change updates the public API in any way, please add a bullet point to CHANGES.md.
• ❔ Unit tests were not updated.
  • Make sure you've updated tests to reflect your changes, added tests for any new code, and ran the code coverage tool.

Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.

[ptrgags]

I noticed that toggling attenuation should trigger a rebuild of the pipeline. I have some ideas on how to refactor the pipeline creation to do this.

[ptrgags]

Here's another local sandcastle that uses point cloud attenuation on an individual ModelExperimental:

glTF	with point cloud shading	with custom shader	with both

The custom shader does not have a custom vertex shader, so the point cloud attenuation's point size does get used, while the custom shader sets the color.

@lilleyse this is ready for review now

[ptrgags]

Also I opened #10005 about eye dome lighting for individual models (right now only 3D Tiles EDL works)

[lilleyse]

Looks great! Tested a few sandcastles before/after and the results look the same.

[ptrgags]

@lilleyse updated!

[lilleyse]

👍