Lasse Öörni, known as Cadaver, makes Commodore 64 games and tools and publishes explanations of how they work. His site brings together the Metal Warrior games, tools including GoatTracker, and a series of technical articles headed Rants.
Those pages are useful evidence for the work itself. They do not supply a complete independent biography, and the credits of each game still need to be read individually. A project catalogue is not a claim that one person supplied every contribution to every release.
Explaining the choices
In Multidirectional scrolling and the game world, Öörni separates the game’s world from the part currently visible on screen. A map can describe a larger area using blocks, while the display routines translate the relevant portion into characters and colours.
He credits Jukka Tapanimäki’s C64 Pelintekijän Opas and his brother among the influences on his approach. The article presents a method he has used, rather than declaring a universal best scrolling routine. That makes its assumptions part of the explanation: a different game may want a different map structure or use its memory differently.
Sharing time with the display
His article on frameskip and interpolation starts with a familiar division: a raster interrupt handles time-sensitive work such as music, while a main loop performs movement, enemy behaviour and scrolling. It then examines what happens when the main work does not finish in one frame.
The proposed techniques change how updates are scheduled and shown. They do not create more processor time. Interpolation also adds bookkeeping, so it needs to earn its place in the game. This discussion sits naturally beside frame timing, where the deadline matters as much as the routine’s isolated speed.
Tools alongside the games
Building a music routine explains the repeated work behind a SID tune: reading musical data, setting a note and continuing effects on subsequent updates. GoatTracker provides a related practical route for preparing C64 music through a development tool.
Öörni’s contribution to this subject includes making those decisions inspectable. The games show results; the tools and explanations give another programmer material to study, adapt and question.
Sources
- Cadaver’s games and tools catalogues: creator-maintained descriptions and project credits.
- Cadaver, Multidirectional scrolling and the game world, Rant 4.
- Cadaver, Building a music routine, Rant 6.
- Cadaver, frameskip and interpolation article, Rant 9. These are original technical explanations, not independent biographical reporting.