Welcome back! This is week 9 of my GSoC project, and we’re very close to full DOS support for the Dungeon Master engine. Sound is working, graphics are mostly in place — the last remaining issue is corrupted wall graphics, which I’ve been digging into this week.
The Wall Atlas Problem
In the original Amiga version, the Left, Center, and Right walls for a given depth were stitched together into one wide “atlas” image — for example, D3LCR combined all three walls for Depth 3. When drawing, the engine would use an X-offset (srcX) to pick the right piece:
- Left Wall (
D3L):srcX = 0 - Center Wall (
D3C):srcX = 61 - Right Wall (
D3R): offset further right
When the game was ported to DOS, this atlas approach was abandoned. The Left and Right walls became their own standalone, tightly cropped images, and the D3LCR file was repurposed to contain only the Center wall.
This is where things get tricky. The engine’s wall-drawing logic was built around the Amiga’s atlas assumptions — offsets, widths, and memory layouts all baked in for that single-image approach. I’m currently working through exactly how to handle this, and hopefully in 1-2 days the dungeon walls will finally look the way they should.
I’ll try to add another detailed blog covering all the code changes by the end of this week. That’s it for this week — see you in the next one! 👋