Say, for example, I wanted to make a block that looked exactly like the oak planks in Minecraft, except that the slats should go vertically instead of horizontally.  Is there a way to accomplish this in model or blockstate files?  All I've seen is the ability to rotate the block itself.

Change uvlock to false, now model rotation will also rotate texture.

But I want to keep the UV lock, I just also want to keep the organization, such as the four cardinal faces having the up and down textures, and then the top and bottom having linked textures.  Basically, I want to be able to rotate the texture before or during application to a block's model without having to make a custom texture just to rotate it 90 degrees.

You can't.

This can be done in the json model. You can write it manually, but it's easier to use MCMC. What you're looking for is Rotation, which can be found under Faces.

 

Yes, but you can't rotate the texture based on block state.  It's baked in.

What about forge's own blockstate json. Can it do that? It has some nifty things . Otherwise you can deff do this using an entity model custom renderer stuff like that.

Yes, but you can't rotate the texture based on block state.  It's baked in.

 

The OP doesn't want to rotate it from the blockstate though. The OP just wants to rotate the texture.

This can be done in the json model. You can write it manually, but it's easier to use MCMC. What you're looking for is Rotation, which can be found under Faces.

Yeah, there was another model creator that I use that I remembered having that, so I looked there.  Needed to make a custom model, but yes, that is exactly what I was looking for.