While many of you were overjoyed to hear that Stunt Car Racer from the C64 had been ported over to both the Atari 8-bit and the BBC micro, you probably didn't know that the Commodore Plus/4 was also getting in on the action! Yes that's right thanks to a heads up via Facebook, we've been told that kaviolalainen has just teased some very impressive footage of the game running on the Plus/4! A version of the game in which he says "The result is somewhere halfway between the Amiga and the C64 visually, which makes it distinct in its own way."
Here is what the creator also says about Stunt Car Racer Plus/4 via the video above "After reverse engineering SCR to modify its physics so it can run at 50 FPS I started looking around and quickly realised that this game hadn't been ported to the Plus/4 yet. Since the TED is in many ways similar to the VIC-II, especially in the absence of sprites, I figured this might be an interesting challenge. And so it was!"
"The biggest limitation was RAM space. The original game doesn't leave much of the C64's memory untouched, and the Plus/4 has less accessible RAM while needing an extra 1K for colour information. For the time being, my solution was to remove load/save functionality and the ability to change key bindings, so I'd be able to get a working game and have some breathing room to shuffle things around. At the moment I have a bit over 2K memory left, so I should be able to restore some of the missing bits."
"I really like the way the game looks with the rich TED palette, even if the multicolour mode limitations (i.e. only two unique colours per block available) were sometimes difficult to deal with. The result is somewhere halfway between the Amiga and the C64 visually, which makes it distinct in its own way."
Awesome
ReplyDeleteAwesome
ReplyDeleteHow to turn a Plus4 into a C64 volume 1! Fantastic job ! I can hardly believe it ! At this point we would need a time machine and transport this game into the past !
ReplyDeleteAwesome work!
ReplyDeleteMy favourite racer. great to see
ReplyDeleteExcellent!
ReplyDeletePerfect conversion! Still wainting!
ReplyDeleteIs there no download for this awsome game
ReplyDelete?
"After reverse engineering SCR to modify its physics so it can run at 50 FPS "
ReplyDelete^ Does that mean that kaviolalainen was able to make the 50fps version of SCR for the Amiga, or?
No, for the C64 with hardware that offers a turbo mode: https://youtube.com/watch?v=xaCca4zCimc
DeleteOk, thanks for clarifying.
DeleteThis looks really good! Always satisfying to see a plussy game look prettier than its C64 counterpart :D
ReplyDeleteBut I didn’t know the plus/4 had less accessible RAM, what with the whole improved bank switching making 60671 > 38911 bytes available to BASIC (and of course games like these don’t even use BASIC)…?
The Plus/4 loses some of its high address range (over 512 bytes altogether) to the I/O area that cannot be paged out, unlike on the C64. Besides, the colour RAM comes on top of the 64K on the C64, while colour data requires 2K of ordinary RAM on the Plus/4. So you have over 2.5K less RAM left for general purposes when using assembly.
DeleteOh, that’s not as much as I feared (but obviously every additional handful of bytes can matter on these systems)
DeleteGreat conversion! The engine sound would have been better deeper although I don't know if this is possible on the Plus 4.
ReplyDeleteThis is an unfortunate TED limitation: the lowest oscillator frequency is around 108 Hz. You can of course get arbitrary sounds out of it at the expense of CPU time, but that's not really an option in this case, since the game needs all the cycles it can use for a decent frame rate.
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