fix(MeshReflectionMaterial)!: add features/docs, reorganize

[andretchen0]

Problem

Some of MeshReflectionMaterial's features – e.g., features related to "blur" – weren't working.

Solution

Rewrite MeshReflectionMaterial

Playground at /materials/reflection-material

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Problem

MeshReflectionMaterial was undocumented.

Solution

Document MeshReflectionMaterial at /guide/materials/mesh-reflection-material.html

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Problem

blurPass didn't have a way of disposing its resources, leading to memory leaks.

Solution

Add dispose to blurPass and dispose it when necessary.

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Breaking changes

The issue of breaking changes was brought up on the Discord. It was decided that since the material was undocumented up to this point, users probably don't rely on the current implementation, and there was little benefit in avoiding breaking changes.

• blurPass and convolutionMaterial move inside MeshReflectionMaterial and their implementations change. These files were/are undocumented. Their implementations are relatively tightly bound to MeshReflectionMaterial's implementation, so they're not generally useful as written.
• The PR activates a lot of previously non-working features of MeshReflectionMaterial. The visual output of the material is much different, for the same props.
• I added some extra props, to hopefully make it easier to get the desired effects. For example, now the user can control how the strength of the blur effect on rough and smooth surfaces, separately. But that meant changing prop names.

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Related issues

Some NOTE:/TODO:s have been left in the files concerning issues filed against the Tres core.

In particular, the Tres core currently doesn't reattach recompiled materials. Some props changes have to trigger a recompile of the material in order to take effect. Some of those are due to THREE.MeshStandardMaterial's implementation, so can't be worked around here, while still retaining the desired functionality/reactivity.

The material logs warnings if users change props in ways that trigger a recompile specific to this material – e.g., toggling the blur or "depth".

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Room for improvement?

The material extends MeshStandardMaterial.

The material ran into reactivity/recompile issues when "inherited" props/defaults were not written out in MeshStandardMaterial.

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closes #371

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[JaimeTorrealba]

Question as this one have breaking changes, it would be merged into v4? or no problem

[andretchen0]

Question as this one have breaking changes, it would be merged into v4? or no problem

Hey @JaimeTorrealba , I'm merging into v4 because of the breaking changes.

Do you see a problem with that?

[JaimeTorrealba]

Not at all, is just I didn't see the label v4,

[andretchen0]

Not at all, is just I didn't see the label v4,

Ah, gotcha. I set the "merge into" branch to v4 in Github, but had not added the label.

Sorry for the confusion. I just added the v4 label.