Expose Animation Blend Trees in the Editor

[yaustar]

Expose Blend Tree properties in the Editor: https://playcanvas.github.io/#/animation/blend-trees-2d-cartesian

[ellthompson]

This will require creating new state in the AnimStateGraph editor of type BlendTree and BlendTreeNode. BlendTree states should act as normal states with regards to transitions. The user shouldn't be able to transition to BlendTreeNodes, instead BlendTrees and BlendTree states can be connected to other BlendTrees as their children, creating a hierarchy of states.

Selecting a BlendTree state should show an inspector which allows the user to set the blend type of that tree (1d, 2d cartesian, 2d directional, direct) and the positions and default weights of any child states. Setting the positions of 2D states should be possible through interaction of a canvas much like: The results of these blends should be previewable in the BlendTrees inspector, using the animations of any entities linked to the current AnimStateGraph asset.