Calculate inertia using localspeed rather than const speed in target/arcrotate cameras

[georginahalpern]

Rather than multiplying epsilon by a const speed when determining if movement is small enough to be clamped to 0, we are now multiplying epsilon by the localSpeed (which takes framerate into account).

This helps avoid inconsistent motion behavior on higher framerate devices, described in this forum post.

https://forum.babylonjs.com/t/camera-inertia-causes-inconsistent-motion/60633/11

[bjsplat]

Please make sure to label your PR with "bug", "new feature" or "breaking change" label(s).
To prevent this PR from going to the changelog marked it with the "skip changelog" label.

[ReedSyllas]

Hi!

Does speed need to be included in the calculation at arcRotateCamera.ts:1066 and arcRotateCamera.ts:1069? I can see that this.speed isn't there, but I think it should've been?

From my personal testing it seems required. The bad behavior comes back without it.

[bjsplat]

Snapshot stored with reference name:
refs/pull/17197/merge

Test environment:
https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/17197/merge/index.html

To test a playground add it to the URL, for example:

https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/17197/merge/index.html#WGZLGJ#4600

Links to test babylon tools with this snapshot:

https://playground.babylonjs.com/?snapshot=refs/pull/17197/merge
https://sandbox.babylonjs.com/?snapshot=refs/pull/17197/merge
https://gui.babylonjs.com/?snapshot=refs/pull/17197/merge
https://nme.babylonjs.com/?snapshot=refs/pull/17197/merge

To test the snapshot in the playground with a playground ID add it after the snapshot query string:

https://playground.babylonjs.com/?snapshot=refs/pull/17197/merge#BCU1XR#0

[bjsplat]

Interaction tests

https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/17197/merge/testResults/interactionplaywright/index.html

[bjsplat]

Devhost visualization test reporter:

https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/17197/merge/testResults/devhostplaywright/index.html

[bjsplat]

WebGL2 visualization test reporter:

https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/17197/merge/testResults/webgl2playwright/index.html

[bjsplat]

Visualization tests for WebGPU

https://snapshots-cvgtc2eugrd3cgfd.z01.azurefd.net/refs/pull/17197/merge/testResults/webgpuplaywright/index.html