Vertex bone influence limits for 3D tools

MAX_BONE_WEIGHTS.md

engine	max influences / vertex
BabylonJS	8
Cesium	4
Godot	8
Love3D	4
three.js	4
UE4	8
Unity	1, 2, 4, or Unlimited
Windows MR	4

Sources:

• three.js • Suggestion: increase the skinning weight limit per vertex from 4 to 8
• BabylonJS • Implement support for 8 bone influences
• Unreal Engine • What are the Bone Limitations in UE4?
• Unity • Manual: Quality

Blender supports Unlimited for import (and on export has 4 by default but supports Unlimited too)

For reference to people finding this gist from a web search and then wondering if ThreeJS could support a higher limit, my PR shows one way that unlimited bone influences can be supported: mrdoob/three.js#26222