Should everything do everything?

You may have noticed: all of the "artwork types" (objects, terrain, roads, beaches, etc.) now do textures in almost the same way - with a TEXTURE command and a TEXTURE_LIT command. (Two notable exceptions: beaches and forests can't be lit yet. We haven't found a case where this is a goood idea but it may happen...nuclear accident anyone?)

The idea here is to unify aspects of all art files so that when future extensions come along, they can be used everywhere. For example, some day we will have textures whose choice is controlled by datarefs. When this happens, because every art file uses a similar mechanism to find textures, we can introduce commands not only in the terrain, but also in objects, facades, roads, etc. so that any type of art can be made seasonal.

This got me thinking about whether all aspects of every artwork type should be available in every file. I think the answer is...sometimes. For example, being able to use lit textures
everywhere is a good thing. But should it be legal to make hard polygons out of every art type? Definitely not every type. Terrain's "hardness" for example is decided inside the DSF, so the only question is "how bumpy should the ground be when it is hard". Objects let you control these things per polygon. But if we have hardness for a facade, how would we specify hardness? Perhaps just whether the roof is hard or not...

I think that X-Plane 8.50 will have more overlap in capabilities between the various types of 3-d "stuff" (beaches, objects, roads, etc.) but we still won't have 100% of all features in every file type. Some combinations just don't make sense.