vdub_bobby Posted August 31, 2005 Share Posted August 31, 2005 (edited) While cruising [stella], I came upon this post by Manuel from almost a year ago: Look what I have here for you:http://www.klov.com/game_detail.php?game_id=7402 Instead of doing the 4th incarnation of 2600 Space Invaders, this'd be a way cooler project Well, my curiosity was aroused, so I followed the link to a game called Cosmic Guerilla. It looked somewhat interesting, so I spent some time today making a mockup, and here it is: The left aliens are P0, the right aliens are P1. The "men" in the middle are the missiles flickering at 30 Hz. The extra ships in the very center is the ball. The UFO is positioned both above and below for the purposes of the mockup; I don't believe it appears in both positions simultaneously during gameplay (though I don't know for sure). The bullets fired by the player and the aliens would be the ball; I figure 4 copies (15 Hz flicker) would be ok. Maybe. Would need 5 scanlines between rows to reposition both players, both missiles, and the ball. EDIT: Realized that I can't use the ball for the extra ships in the center of the screen since I am using the ball for the bullets So, extra ships will be PF until they move, then missiles flickering at 30 Hz. Also means I won't need to reposition the ball between rows, so only 4 scanlines between rows instead of 5. /end edit Here's a screenshot from the arcade original: Edited August 31, 2005 by vdub_bobby Quote Link to comment Share on other sites More sharing options...
Cybergoth Posted August 31, 2005 Share Posted August 31, 2005 Hi there! Uhm... as usual... Ok, source is attached, feel free to use it... or don't Greetings, Manuel cosmic.zip Quote Link to comment Share on other sites More sharing options...
vdub_bobby Posted August 31, 2005 Author Share Posted August 31, 2005 (edited) Hi there! Uhm... as usual... [image]http://home.arcor.de/cybergoth/xype/cg.gif[/image] Ok, source is attached, feel free to use it... or don't Greetings, Manuel 922597[/snapback] I knew I should have looked around a little before going to all that work. Oh, well - it was fun anyway. And I think I like my mockup better Edited August 31, 2005 by vdub_bobby Quote Link to comment Share on other sites More sharing options...
Cybergoth Posted August 31, 2005 Share Posted August 31, 2005 Hi there! Oh, well - it was fun anyway. And I think I like my mockup better Yeah doing such stuff is amazing fun and that's all that matters Anyway cool, go ahead! I still think Cosmic Guerilla would make a very good 2600 game. No clue why I stopped back then, I guess I just got hit by the shiny object syndrome Greetings, Manuel Quote Link to comment Share on other sites More sharing options...
vdub_bobby Posted August 31, 2005 Author Share Posted August 31, 2005 I still think Cosmic Guerilla would make a very good 2600 game. Well...it would make a good 2600 game, except for the fact that the 2600 already has about a million 2D non-scrolling shooters. Probably a good project for a beginner. Quote Link to comment Share on other sites More sharing options...
uosipa llamxew Posted August 31, 2005 Share Posted August 31, 2005 Well...it would make a good 2600 game, except for the fact that the 2600 already has about a million 2D non-scrolling shooters. Probably a good project for a beginner. 922690[/snapback] It'd make a great game (period) The game is just different (and fun!) enough from other 2600 shooters that I think it would fit quite nicely into the homebrew library. Great mockup, btw. I think I'm going to run try Cybergoth's .bin now. Quote Link to comment Share on other sites More sharing options...
vdub_bobby Posted September 2, 2005 Author Share Posted September 2, 2005 (edited) Ok, here's a real mockup. No pic because there is some flicker and it looks bad with only half the objects. EDIT: Ok, here are two pics, each showing one half of the 30 Hz flicker. The bullets are flickered at 15 Hz so I would need 4 pics to show 'em all. cg.bin Edited September 2, 2005 by vdub_bobby Quote Link to comment Share on other sites More sharing options...
Cybergoth Posted September 4, 2005 Share Posted September 4, 2005 Hi there! Ok, here's a real mockup. Wow! Almost there! Hm... my design was heading for less flicker though it seems (And my Aliens look better ) Greetings, Manuel Quote Link to comment Share on other sites More sharing options...
Mayhem Posted September 4, 2005 Share Posted September 4, 2005 There's also a version for the Vic20 (well two actually) you can check to see how they compare: Cosmic Jailbreak and Ape Escape. Quote Link to comment Share on other sites More sharing options...
vdub_bobby Posted September 6, 2005 Author Share Posted September 6, 2005 Hi there! Ok, here's a real mockup. Wow! Almost there! Yeah. I'm not entirely pleased with it, though. Ended up with 7 blank lines between rows, which both limits the number of rows (from arcade 15 to VCS 10) and also compresses the playfield vertically. Too much, I think. Hm... my design was heading for less flicker though it seems My mockup matches the arcade gameplay better, though Quote Link to comment Share on other sites More sharing options...
Cybergoth Posted September 6, 2005 Share Posted September 6, 2005 Hi there! My mockup matches the arcade gameplay better, though Hehe... only because mine isn't finished yet Greetings, Manuel Quote Link to comment Share on other sites More sharing options...
vdub_bobby Posted September 6, 2005 Author Share Posted September 6, 2005 Hi there! My mockup matches the arcade gameplay better, though Hehe... only because mine isn't finished yet Greetings, Manuel 926311[/snapback] Perhaps. More seriously, using the playfield for the "men" would make it difficult to duplicate the gameplay of the original, plus it would make your kernel a real bear since it would require a full asymmetrical playfield! Or maybe...hmmm... Quote Link to comment Share on other sites More sharing options...
Cybergoth Posted September 7, 2005 Share Posted September 7, 2005 Hi there! More seriously, using the playfield for the "men" would make it difficult to duplicate the gameplay of the original, plus it would make your kernel a real bear since it would require a full asymmetrical playfield! Or maybe...hmmm... I honestly no longer remember what my plan was. Buffering the playfield for 11 rows would be 44 bytes. Then you'd have coarse movement. If you'd buffer only PF2, then that'd be 22 bytes. You'd then use a particle at 4 pixels width for soft movement. What I'm mainly missing is the plan I had (if any...) for the extra ships residing in the middle... Greetings, Manuel Quote Link to comment Share on other sites More sharing options...
vdub_bobby Posted September 7, 2005 Author Share Posted September 7, 2005 Hi there! More seriously, using the playfield for the "men" would make it difficult to duplicate the gameplay of the original, plus it would make your kernel a real bear since it would require a full asymmetrical playfield! Or maybe...hmmm... I honestly no longer remember what my plan was. Buffering the playfield for 11 rows would be 44 bytes. Then you'd have coarse movement. If you'd buffer only PF2, then that'd be 22 bytes. You'd then use a particle at 4 pixels width for soft movement. What I'm mainly missing is the plan I had (if any...) for the extra ships residing in the middle... Greetings, Manuel 926776[/snapback] I was just thinking - this thought began to form yesterday; the reason for the "hmmm" - if you used the PF for the "inner" men and used the missiles for the "outer" men, then you could eliminate flicker entirely; this would be similar to how I am displaying the extra ships in the current demo - using the playfield when they can't move (i.e., men are still protecting them) and then using a missile when they are movable. If I extend this concept to all the center objects, since only two center objects on a row can move at the same time, then you wouldn't need to flicker anything. Well, except for the bullets; I still don't see a way around using the ball for all the bullets flying around the screen. That would require an asymmetrical PF2, though, which would complicate the kernel a little. Maybe not too much, though. Quote Link to comment Share on other sites More sharing options...
~llama Posted September 8, 2005 Share Posted September 8, 2005 Is this turning into a Cosmic Guerilla kernel arms race, to see who can make a better kernel? That'd be an interesting competition, to get all of the 2600 wizards together and have them all turn out kernels for a port of Cosmic Guerilla, and then see whose is best maybe not though... I like where this thread is headed, though. I played Cosmic Guerilla in MAME the other day after finding this thread and I think it'd be great on the 2600-- I'd buy a cart. Quote Link to comment Share on other sites More sharing options...
Kurt_Woloch Posted June 12, 2009 Share Posted June 12, 2009 OK, sorry to dig out this old thread here, but there has been another variation on Cosmic Guerilla posted, called Strip off. It's here: http://www.atariage.com/forums/index.php?showtopic=145539 And that reminded me of this thread. Seems like the effort here dried down before the game was finished, though Bobby's version looked quite far along, and I think it could have evolved into a complete game if work on it would have been continued. Actually, I would have had even different ideas for the kernel... also taking into account the enhanced "Cosmic Do!" version. I probably would have tried to reduce flicker in the "normal cases". A "normal case" for me would be a row where nothing is moving at the moment, meaning that all men which are still there are in the middle, and all aliens which are still there are on the left or right. In that case, both aliens could be displayed using one player with 2 copies. And as soon as an alien strays off, the two aliens could be displayed alternatively with a 30 Hz flicker. This would free up one player on each row for other purposes, for instance, for the men or for the extra ship. In this case, I would use the second player to display the men. Since a player is 8 bits wide, three of them could be used to display three men next to each other. And that player could be duplicated so that it displays both sets of men, on the left and on the right, in the same frame. The only downside of this would be that the pattern of that player would have to be re-written in mid-scanline. But that way, if the ball or the playfield gets used for the extra ships, a "normal" row could be displayed without any flicker. OK, it's also displayed without flicker in Cybergoth's version... but anyway, these would be my ideas. Quote Link to comment Share on other sites More sharing options...
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