emux

That was just my collection which I was cataloging a few years ago so it's not what you might call a scientific result but my feeling at the time was that the VSP problem was not that widespread. The machine that failed was a later HMOS - C64C type machine.

I don't think it's true to say that it "only works on a fraction of the exist machines". I've tested over 20 C64's and all of them apart from one was VSP safe, so only one failed the test. Also I'm not seeing much feedback from user's saying that this port is crashing on their machines. Also all of the C64 emulators are VSP safe as well as the C64 Re-Loaded 1&2, Ultimate 64 and TC64 - all VSP safe. It's such an obscure problem that an emulator would have to build it in rather than it happen by default.

I think both versions of the music are great, I guess it just comes down to personal taste at the end of the day. The SID versions were done first and make use of the SID's filter a lot. I would imagine its the filter that makes the biggest difference between the two versions. I could be wrong but I would imagine that the notation is more or less the same. IMO both versions are way better than the Z80 versions music. They use very generic tunes.

Having worked on the CBM versions I have to say Mariusz did an amazing job on the Z80 to 6502 conversion of this game. Like he said the Z80 version was already heavily optimized yet all the 6502 versions run as fast or almost as fast as the Spectrum version and yet this game was written very much with the Spectrum's hardware in mind!

Yeah, Delta lends it's self to that type of sprite arrangement and it also used sprites in the border to good effect as the C64 can't overscan. Also by using sprites as the background it did away with the need to have to build the screen every 8 pixels for the scrolling which would have saved some raster time. The best early use of sprite multiplexing on the C64 IMO was Terra Cresta in 1986 (a very underrated game in my option) which had loads of sprites flying around and sorted without much glitching. The Ocean programmers were very good, it's a shame they didn't release more stuff on the A800.

Hello everyone, Delta on the C64 has an unusual display system in that all the background graphics and sprites are made of hardware sprites and only the stars and bullets are made of characters. Not sure why he coded it like that but he did!