DescentBB

So there are some places in a level where I want to have light without a light texture being there. I know you can temporarily put a light texture there, run the light tool, and then remove the light texture. This works well for my inquiry. However, this means I have to temporarily set the textures all over the level, and if I want to make ONE change to the lighting, then I gave to temporarily do it all over again. This makes it difficult to make one change.

So my question: Is there another way to set lighting to a face or segment without temporarily adding a lamp texture and running the light tool?

Yes it can be done, but it's actually easier to run the light tool and remove the textures. I used to manually light my mines by adjusting the cube light for all the vertices, but that's a huge pain in the but. Hopefully someone else will come to this thread and offer a shortcut. I don't know of any off-hand, though I've only made about a dozen mines.

With all that was done with DLE, there's gotta be a way to run the light tool for only a selected or tagged segment or face.

I mean there technically is, but from my experience it typically results in the editor crashing.

As far as lighting a face without a light, there are ways to do it without a visible light, but there is still a light there. This can be done either by making the primary texture a light of choice and putting a solid texture as the overlay, or by using the empty_light texture as an overlay (which was designed for this purpose).

I didn't know there was an empty_light texture. Which one is it?

In the light section of the texture picker there is a solid white texture. This is the one.

I noticed the brightness slider in the texture tab at the bottom. This seems to do that. I still have to experiment around with it to get a feel for it.

Yeah, these days with DLE that's a much easier way to do it, gives you more control, and it looks better.
It is designed to work especially with D2X-XL, which I think can read the brightness values directly, but it also bakes the resultant lighting into the map for every other version of the game.