John Brooks: This project was extremely demanding technically, with problems that I don't believe were solved by others either before or after SMWW. There were 7 critical problem areas in doing a high-quality Mario platform game on CD-i.
1) No tiled graphics or scrolling hardware, which made platform games extremely difficult.
2) No sprite overlay hardware.
3) No audio mixing hardware (combining sounds effects with music).
4) OS-9 made hardware access difficult and caused performance spikes, which interfered with 60hz performance.
5) Sound effect lag due to audio decompression (ADPCM) buffering.
6) Input response lag from the wireless remote.
7) Matching the extremely high quality feel of Super Mario World.
Problems 1, 2 and 3 were overcome with innovative programming solutions, some of which were extensions of work that I had previously done on Rastan Saga (Apple //GS). Problem 4 was minimised by writing low-level OS-9 drivers. Problem 5 was minimised by using 'A stereo' ADPCM mode which had the least latency through the audio chip. Problem 6 was a hardware issue with no known solution. Problem 7 was an on going problem for me. I painstakingly explored, tested and refined the game feel to match that of Super Mario World. Although I only partially implemented them, I was thoroughly impressed by the subtlety and intuitiveness of the Super Mario control, animation and movement models.
[Thanks, John Brooks, who was a programmer on Super Mario's Wacky Worlds on CD-i at NovaLogic]