I am developing an FBShader plug-in that I want to be able to control via the relation editor.  I see that FBShader derives from FBBox, and I am able to create HFBAnimationNode members via the AnimationNodeInCreate method.  However, I cannot see these properties in the relation editor like I can for other plugin types.  What more do I need to do to expose these inputs?

I can drag the “Lighted” shader, “Relation” constraint and “Mouse” device from asset browser. and then I can connect the Mouse with Lighted’s Alpha property inside relation constraint.

maybe you want to create a animated property for your shader and use it for connection.