+Vorticon Posted December 1, 2015 Author Share Posted December 1, 2015 Having played the Vic20, BBC Micro and ZX Spectrum versions, I think I can say that this version compares best with the original. This was also true of SabreWulf and Jet Set Willy, it seems that the 4a is well suited to Spectrum conversions. Thank you! There is definitely a speed difference given that the TI version is coded in TF and not in assembly. That said, the final version will be a speedier. I'm just waiting for all the background code to be in place before I tweak the play speed. As you might guess, there is a lot going on on screen! Quote Link to comment Share on other sites More sharing options...
am1933 Posted December 1, 2015 Share Posted December 1, 2015 Yes. The spectrum and the TI have the exact same screen resolution: 256x192. That makes things a lot easier. I think that the TI colour palette has a bit to do with it also, the TI and the Spectrum are both blessed with a vibrant colour set and in general do not suffer from the memory/colour/resolution trade off that blighted a lot of the competing machines of the time. Quote Link to comment Share on other sites More sharing options...
Opry99er Posted December 1, 2015 Share Posted December 1, 2015 Daaaaang, looking good, Vorticon!!! Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted December 1, 2015 Share Posted December 1, 2015 Man now I'm gonna have to get a turboforth cart Hmmm, I'll have to check, is there an image available for Turbo Forth that will fit into a 512K chip for the Blue Board? Quote Link to comment Share on other sites More sharing options...
+Lee Stewart Posted December 1, 2015 Share Posted December 1, 2015 Hmmm, I'll have to check, is there an image available for Turbo Forth that will fit into a 512K chip for the Blue Board? TurboForth is a 16KiB, 2-bank binary set up for banks 0 and 1. Ordinarily, you would use a black board jumpered for a 27C128 EPROM. If you use an EPROM of a larger size, you would need to replicate the binary to fill the empty banks so TurboForth starts properly. If you are using the blue board (non-inverted bank order) for more than one cartridge, TurboForth must be in the first two banks with the banks in the reverse order they have for the black board (inverted bank order). ...lee Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 OK version 0.8 of Jetpac is up in the first post. Essentially the game is complete except for sound effects and a splash screen. There is still an intermittent bug in the 2 player mode which I'm hunting down. Once Old CS1 sends me the sound samples, I'll add them in. Here's my less than stellar play with this latest version. Please let me know if you come up with any bugs or if you have any suggestions for improvement. I did end up slowing down the monsters a bit to make the game more playable, at least for me! https://youtu.be/_3Y_LwLFhUs 1 Quote Link to comment Share on other sites More sharing options...
Opry99er Posted December 3, 2015 Share Posted December 3, 2015 Man, that is looking cool.... Very glad to see you have come so far. Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 Thanks Fun project, but definitely out of my comfort zone since I don't usually tackle arcade games. 1 Quote Link to comment Share on other sites More sharing options...
InfernalKeith Posted December 3, 2015 Share Posted December 3, 2015 Love it! I've never played the other platforms' version of this game, but you've captured the atmosphere of that mid-80's Speccy/Commodore type of game. No one who sees this would think of such games as "out of your comfort zone" at all. Great work. 1 Quote Link to comment Share on other sites More sharing options...
Opry99er Posted December 3, 2015 Share Posted December 3, 2015 Looking forward to the finished package. Surely you will do a polished release like you did with Panzer Strike, yes? I have real dollars for that kind of action. 1 Quote Link to comment Share on other sites More sharing options...
Willsy Posted December 3, 2015 Share Posted December 3, 2015 Love it! I see on later levels the nasties actually home-in on your location. Love it love it love it! I feel like a proud parent It gives me a big buzz to see someone use TF and get really great results with it! Top job! :thumbsup: 1 Quote Link to comment Share on other sites More sharing options...
am1933 Posted December 3, 2015 Share Posted December 3, 2015 It is looking damn fine!!!!, just one thing though-(isn't there always). I see that you have slowed down the monsters, would it be possible to take them back up a notch-maybe 10 to 15%. No major big deal, I just want to preserve the bragging rights with Spectrum owners 2 Quote Link to comment Share on other sites More sharing options...
Willsy Posted December 3, 2015 Share Posted December 3, 2015 No major big deal, I just want to preserve the bragging rights with Spectrum owners Ha! LOL! Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 It is looking damn fine!!!!, just one thing though-(isn't there always). I see that you have slowed down the monsters, would it be possible to take them back up a notch-maybe 10 to 15%. No major big deal, I just want to preserve the bragging rights with Spectrum owners There is unfortunately no delay or timing loop I can tweak for the monsters. Their velocity can only be incremented by whole pixels at a time. Currently they move one pixel per pass through the main game routine. I had them originally at 2 pixels, but I felt that was too fast, at least for my reflexes. I'll post an amended listing later today with the faster monsters and let you guys decide what feels best for play. Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 Looking forward to the finished package. Surely you will do a polished release like you did with Panzer Strike, yes? I have real dollars for that kind of action. Absolutely Now I wonder if there is a way to create a cartridge which will have both TF and Jetpac on it, where Jetpac will autostart when TF is selected from the main menu. I know next to nothing about making carts and such, so this is an open question to Willsy, ksarul, Tursi, Jon and others. Is it possible? 1 Quote Link to comment Share on other sites More sharing options...
Willsy Posted December 3, 2015 Share Posted December 3, 2015 It's probably possible. You'd need an (at least) 32K cartridge EPROM - 16K for TF and 16K for the compiled Jetpac Binary. The version of TF in the EPROM would be modified to copy the binary out of the EPROM into the 32K and then run it. 1 Quote Link to comment Share on other sites More sharing options...
Iwantgames:) Posted December 3, 2015 Share Posted December 3, 2015 Man if this comes to cartridge I'll be all over it like fly's on a cow pie Quote Link to comment Share on other sites More sharing options...
+Lee Stewart Posted December 3, 2015 Share Posted December 3, 2015 Absolutely Now I wonder if there is a way to create a cartridge which will have both TF and Jetpac on it, where Jetpac will autostart when TF is selected from the main menu. I know next to nothing about making carts and such, so this is an open question to Willsy, ksarul, Tursi, Jon and others. Is it possible? It's probably possible. You'd need an (at least) 32K cartridge EPROM - 16K for TF and 16K for the compiled Jetpac Binary. The version of TF in the EPROM would be modified to copy the binary out of the EPROM into the 32K and then run it. Well, this will be difficult because There is no room in the TurboForth ROM space to put any code to handle this without first removing code that Jetpac may not need and Jetpac uses almost 22KiB of RAM, which would require a 64KiB EPROM. It is possible, of coures; but, there is work to be done! ...lee Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 Now that is great news. What will be required of the Jetpac code to make this feasible? Quote Link to comment Share on other sites More sharing options...
Willsy Posted December 3, 2015 Share Posted December 3, 2015 As Lee says the first thing to do is remove some stuff from TF that Jetpac doesn't need to make room for the bootstrap code. The bootstrap code will copy a routine into pad ram which in turn banks in the appropriate banks in the eprom and copies the contents to CPU ram. Quote Link to comment Share on other sites More sharing options...
Willsy Posted December 3, 2015 Share Posted December 3, 2015 If you want a splash screen then you're looking at an additional 12k on top of the 22k! Quote Link to comment Share on other sites More sharing options...
Willsy Posted December 3, 2015 Share Posted December 3, 2015 There's code in TF which scans the keyboard at start up and loads BLOCKS from a drive according to the key pressed, or bypasses booting if enter is pressed at startup. I guess I'd strip that out first. That might be enough. Also only one cartridge header is required. Probably all the block related words could be removed since it wouldn't need to do any disk access. Plenty of scope to do it. Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 If you want a splash screen then you're looking at an additional 12k on top of the 22k! Yes. We're going to need a bigger cartridge Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted December 3, 2015 Author Share Posted December 3, 2015 Here's a snapshot of the game with the faster monsters. I must admit that this looks better even though now my score is abysmally low, so I'm making it official as version 0.85. I also hunted down and squashed the intermittent 2 player bug and made a couple of minor enhancements to the code along the way. https://youtu.be/gUqSojbV2aY 2 Quote Link to comment Share on other sites More sharing options...
Tursi Posted December 3, 2015 Share Posted December 3, 2015 Also only one cartridge header is required. I recommend against that, since it means that if the system is reset during game play there's a good chance the cartridge will be in the wrong bank, and won't show up in the selection menu without a power cycle. 64k isn't even a big ROM today, go for it! Quote Link to comment Share on other sites More sharing options...
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