Add overrideRenderingFillMode property to Mesh

[sebavan]

Supersedes #13688

As discussed in forum thread here: https://forum.babylonjs.com/t/add-mesh-overridematerialfillmode/39475/

cc @MiikaH to review

The main difference is use the override only within the rendering scope as the flag is only used as a visual tool. It also fixes some of the scene override levels inconsistencies.

[bjsplat]

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[bjsplat]

Snapshot stored with reference name:
refs/pull/13708/merge

Test environment:
https://babylonsnapshots.z22.web.core.windows.net/refs/pull/13708/merge/index.html

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https://babylonsnapshots.z22.web.core.windows.net/refs/pull/13708/merge/index.html#WGZLGJ#4600

Links to test babylon tools with this snapshot:

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https://sandbox.babylonjs.com/?snapshot=refs/pull/13708/merge
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[MiikaH]

Nice! That seems to work perfectly in my playground test case: https://playground.babylonjs.com/?snapshot=refs/pull/13708/merge#WX0F9G#2

That being said. In my forum post use case I do clone the mesh and change index buffer to special index buffer to render ngon wireframes. Material is shared, but geometry as a whole is not. However at least in my use case the override is only used for rendering so I have no complaints what-so-ever about this getting merged in a simplified render only form. :)

[sebavan]

@Popov72 any thoughts ?

[Popov72]

I think we can merge this PR and see if there are other needs in the future?

[MiikaH]

Hmm.. I just noticed that you moved the fillMode assingment inside _processRendering().

That might be a problem? Right now:

• Mesh.render() has unnecessary scene override assingment to the fillMode variable, only to be overridden again by the new call.
• There are other areas of the code that call _processRendering() that may not want to apply the scene or mesh override? Such as VolumetricLightScatteringPostProcess

If this is kept as "render only" override, then it likely should be applied outside _processRendering() only for code paths that render final images (Mesh.render() and EffectLayer)?

[sebavan]

There are other areas of the code that call _processRendering() that may not want to apply the scene or mesh override? Such as VolumetricLightScatteringPostProcess

It is more a bug in the previous implementation as it should use the requested fill mode and not force triangle which might even not fit with the content. (let s not that this might also be a problem with the override today but I prefer to wait for a REAL usage rather than introducing more code if it is never even used)

Mesh.render() has unnecessary scene override assingment to the fillMode variable, only to be overridden again by the new call.

Good catch, fixed in the latest push and checked in the code base.