All of this information was obtained by modifying the file Phoebus_16x16_Meld.png, from Phoebus' most recent complete graphics pack. I made my own version of each of the wall tiles and then put a black dot in three of the corners of the L shapes to determine the inner workings of those tiles by trial and error.
Info on the number of different wall tiles...
Essentially there are 20 different tiles devoted to walls. Out of that, 12 are the L shaped walls, 3 of each type, differing based on their connection to either another wall or to rock. The next most numerous is the three way split, of which there are 4, based on the direction of the connections and only occurs when three of the four N S E W directions are connected to another wall. There are N/S and E/W connectors, pillars, and four way (doubles as fortification) tiles. If a wall is connected to another wall (and no natural rock) in only one direction it is drawn as a pillar (pillars are end pieces and stand alone tiles).
Wall tiles take on the color of the stone they are dug in to or built out of. To my knowledge they only use one color, and the background color is black, unless it is engraved then it becomes something whiter.
Q 1: Is there a way to determine what tile is drawn based on the connections in the raw files? If not, is there any other way? It seems like a waste to have so many tiles taken up by the L shaped pieces.
Q 2: Are engravings just a recoloring of wall tiles (the background color) by default? Or are they handled in some more intricate way? If it has much to do with the raw files I may just have to dive in to that tomorrow.
Q 3: Anything else I should know about walls in particular?
I've learned a lot through the editing that I've done today.. Put in a good 4 solid hours at least just fooling with things and I have some product as well (still not finished).
Here's a pic of what I've managed to do.
Walls with dotted lines parallel are engraved. I also redid the staircase up.Thanks everyone for the help that you've given me. I really appreciate it, and will continue working on my tiles thanks to you all.
Cheers!
Graham