This is an experimental game. It uses 3D spatial coordinates and meters to determine position, physics, hit detection, and sprite scale (features passed on to bonefinity–see below). This game manually loads Targa files (loader is still in bonefinity). If I had to do it over, I would have used a good image library instead, but I wasn’t aware of one for DirectX. It is the first graphical program I created in C++, so it has many other problems as well (mostly redundant code due to lack of configurability).
I created the first working version in DirectX 7 while reading Tricks of the Windows Game Programming Gurus by Andre LaMothe. The book uses highly optimized C code, which is a nightmare to learn or maintain (especially as a solo coder or beginner). If you are a game engine designer, find a good game engine design book. If you are not, I recommend you use an existing game engine so you can really focus on game design.
Every now and then I improve the experiment, and it is often something I use as a testing ground for new skills. I have also gotten helpful feedback on the game. I have converted it entirely to C++ and SDL. There is also an SFML fork, which is not playable yet.
Any updates or a real game based on this experiment will be posted below.