I have documented every byte of the Lander game code, but that doesn't mean that I've fully understood every byte (though it's close). Almost every single aspect of the code is explained, but there are a few issues that could benefit from another look.
This page lists all of the outstanding issues of which I am aware. These are the notes I made as I analysed the source, so they are fairly terse and might not be terribly clear.
Maths (Geometry)
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- ProjectParticleOntoScreen: Why is 64 added to y, not 128?
- ProjectVertexOntoScreen: Why is 64 added to y, not 128? And why is R6 scaled by R14+1?
Drawing triangles
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- DrawTriangle (Part 4 of 11): Logic in very last part seems the wrong way around
- DrawTriangle (Part 9 of 11): Logic in very last part seems the wrong way around