add feature to output node to add other inputs

Hi Phil,

It's not that easy, a material is a complex "object" that requires different type of data to work.
For example, in your base color you will only send color information when for a height map you will work in grayscale and send relief information.
In Designer, if you go into Material -> Default -> Edit, you will see which information the shader is able to take as input. The outputs of your graph are the inputs of the shader, each outputs of your graph has to fit with each inputs of the shader, that's why on outputs node you have to set a usage.

You can add several usages on an output node but you have to be sure what you will set as input of this node will work for your different usages and most of the time, it won't. 
A case where it can work it for coating effect. You can set a coat normal and this map can be the same as your 'classic' normal map. In this case, you can define the two usages in your output and use the same normal map to control the normal and coat normal.

Now if it's only a UI matter, we could imagine having a big node with all usages defined as input but it wouldn't be very handy to use or read.

Thanks for your feedback 🙂  
 
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