No idea how to fix the first ones, but if the displacemet surfaces are perfectly fat in map #2, why not use brushes?
I need to be able to use blending on the ground there.
Ok, I've slept on it and have calmed down a bit. Let's take a step back for a moment and look at the original geometry I used for my displacements.
Before being displacements,
this terrain looked like this:
It was then turned into displacements, subdivided, and noised up accordingly.
And before being flat displacements,
this section of the ground looked like this:
I did it this way so that the ground would wrap perfectly around all the walls/buildings, ergo making texture blending around the walls much easier to manage. And it
was easier to manage until this lighting issue came up.
Now what is inherently wrong about making displacements like this? I know I'm not the only one to do it this way. Everybody doesn't just build perfect displacement squares and go about their merry way. And why does Source have this tendency to fuck up lightmaps on displacements?
If I absolutely, positively have to make squares and rectangles out of the flat part then I will, but I know it will be a pain in the ass to manage in Hammer and it won't actually fix the problem that is affecting both my terrain and the flat part. I can't just make squares out of the cliffs, and I'm using exactly the same method that the Dear Esther guy is using.
I'm considering just emailing the guy and asking him how he avoided it.