Lazycow Posted June 14 Share Posted June 14 (edited) Hi Atariage, I came up with an idea how to create backgrounds with more than two colors per line and decided to revive my 10 year old Atari project. Working title for a potential run'n'gun minigame: Powercore left: mockup, right: screenshot of 1st test The 1st kernel test successfully displays the background and a multicolored P0 sprite. It's not featurecomplete, yet. But there're some free CPU cycles left. Horizontal softscrolling test: (not playable) scrolltest1-ntsc.bin scrolltest1-pal.bin Edited July 5 by Lazycow 16 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 14 Share Posted June 14 Variable midline PF color changes? Seems tricky. Especially when combined with PF, sprites and sprite colors changes. I figure this not a stock 6507 doing the work? Quote Link to comment Share on other sites More sharing options...
Lazycow Posted June 17 Author Share Posted June 17 Update: Horizontal movement and animation of P0 works now. @Thomas Jentzsch Yes. Although... "tricky" is an understatement. But I might be biased, because it's my 1st Atari kernel. No DPC, no flickering, no illegal opcodes. 9 Quote Link to comment Share on other sites More sharing options...
Silvio Mogno Posted June 19 Share Posted June 19 On 6/17/2024 at 9:22 PM, Lazycow said: No DPC, no flickering, no illegal opcodes. Using this features is not evil! 😅 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 19 Share Posted June 19 (edited) 2 hours ago, Silvio Mogno said: Using this features is not evil! 😅 Right, they are not illegal, just undocumented. Edited June 19 by Thomas Jentzsch 1 Quote Link to comment Share on other sites More sharing options...
Lazycow Posted June 21 Author Share Posted June 21 Update: Added a color table for the 3-color-background. And a multicolored P1 sprite. The available CPU time in the kernel segments is getting critical now, I can only change the P1 sprite color every 2nd line. But that seems to be acceptable for the game graphics. And I couldn't find a way to change the horizontal sprite pos with RESP1 in the middle of the screen. Backup plan: Moving P1 with HMP1. (Drawback: Enemies can only be placed every 2nd stripe) @Silvio Mogno Fair enough, I will probably feel more relaxed now when one of the sprites starts flickering... 😉 5 Quote Link to comment Share on other sites More sharing options...
glurk Posted June 21 Share Posted June 21 You might take a look at the undocumented instructions too. They work on all real 2600's and can sometimes save a few cycles that cannot be saved in any other way. The DCP inst. is particularly useful is sprite drawing. But clever uses can be found for many of them. 2 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 21 Share Posted June 21 Are you going to post a binary? 1 Quote Link to comment Share on other sites More sharing options...
Lazycow Posted June 23 Author Share Posted June 23 1st test on real hardware. (PAL) Compared to the emulator, the colors are a bit off. (I wonder if this is caused by a not optimal adjustment of my AV mod) The horizontal displacement of the enemies is done by HMP1 only. (without RESP1) Seems to work. (Although, there's a bug at sprite #2) @glurk Yes, I know DCP (and LAX) and I'll keep an eye at them. Right now, there's no need to use them, but we'll see... @Thomas Jentzsch Yes, maybe at a later date, when there's something to see or something to play. 5 Quote Link to comment Share on other sites More sharing options...
Lazycow Posted June 28 Author Share Posted June 28 Update: A scrolling testroom with some enemies Who said the Atari 2600 cannot do horizontal softscrolling? 8 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 28 Share Posted June 28 33 minutes ago, Lazycow said: Who said the Atari 2600 cannot do horizontal softscrolling? ROM or it didn't happen. 4 Quote Link to comment Share on other sites More sharing options...
Lazycow Posted July 5 Author Share Posted July 5 Update: Added a Test-Kernel that can display M0 and M1. (Without missiles, a run'n'gun like game would be senseless) It's not working with scrolling. At least, not yet. @Thomas Jentzsch Fair enough, I added the scrolling-test as download in the 1st post. 5 Quote Link to comment Share on other sites More sharing options...
+splendidnut Posted July 5 Share Posted July 5 Cool demo. The smooth horizontal scrolling is nicely done. 2 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted July 5 Share Posted July 5 (edited) 4 hours ago, Lazycow said: Update: Added a Test-Kernel that can display M0 and M1. (Without missiles, a run'n'gun like game would be senseless) It's not working with scrolling. At least, not yet. @Thomas Jentzsch Fair enough, I added the scrolling-test as download in the 1st post. Thanks! Looks great. Very smart use of background colors. 👍 BTW: I notice a small glitch when the bottom sprites are at the very left. Also this kernel will cause in @ZeroPage Homebrew's console (enable Developer Settings/TIA/delay background color), but I suppose there is not much you can do. Edited July 5 by Thomas Jentzsch Quote Link to comment Share on other sites More sharing options...
+ZeroPage Homebrew Posted July 5 Share Posted July 5 1 hour ago, Thomas Jentzsch said: BTW: I notice a small glitch when the bottom sprites are at the very left. Also this kernel will cause in @ZeroPage Homebrew's console (enable Developer Settings/TIA/delay background color), but I suppose there is not much you can do. Confirmed! Here's a video capture of the test running on my RGB Modded Light Sixer showing the issue. Very innovative and smooth way to scroll platforms using the ball, love it! - James 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted July 5 Share Posted July 5 16 minutes ago, ZeroPage Homebrew said: Confirmed! Here's a video capture of the test running on my RGB Modded Light Sixer showing the issue. I wonder why you invested 100s and 1000s $$$ into your technical equipment for perfect capture. But don't get your 2600 fixed (AFAIK your's is the only one with this problem). Quote Link to comment Share on other sites More sharing options...
JetSetIlly Posted July 5 Share Posted July 5 29 minutes ago, ZeroPage Homebrew said: Confirmed! Here's a video capture of the test running on my RGB Modded Light Sixer showing the issue. Does the RGB mod affect only the COLUBK and COLUPF registers or are all colour registers affected? Quote Link to comment Share on other sites More sharing options...
+ZeroPage Homebrew Posted July 5 Share Posted July 5 46 minutes ago, Thomas Jentzsch said: I wonder why you invested 100s and 1000s $$$ into your technical equipment for perfect capture. But don't get your 2600 fixed (AFAIK your's is the only one with this problem). If I remember correctly it's a bug in the RGB mod that the developer is not interested in fixing. Unfortunately there's no current alternative RGB/component mods* leaving me with only emulation or a much (IMHO) softer svideo alternative. This bug has not been an issue so far as there usually have been kernel timing fixes by developers. At this point I would rather have the higher quality RGB output than to sacrifice picture quality for a very, very small handful of instances where this issue has a minor effect on the look of a game. EDIT: If it affects the game to the point of distraction I can always play it on my SVID modded 7800. 🙂 - James * I still have to investigate the LumaCode TIADigitizer further, but last I read there were some show stopping issues for me. 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted July 5 Share Posted July 5 25 minutes ago, JetSetIlly said: Does the RGB mod affect only the COLUBK and COLUPF registers or are all colour registers affected? AFAIK it's only COLUBK here. Quote Link to comment Share on other sites More sharing options...
JetSetIlly Posted July 5 Share Posted July 5 Just now, Thomas Jentzsch said: AFAIK it's only COLUBK here. Yes. But the RGB mod is what causes the issue with Quickstep isn't it, which is the COLUPF being affected. I was wondering if the other colour registers are affected in the same way. Quote Link to comment Share on other sites More sharing options...
Lazycow Posted July 6 Author Share Posted July 6 (edited) Hey, thanks for the feedback! I've analysed the COLUBK RGB-mod bug. It should be possible to add a game option with a workaround for RGB-mod users. (If the game ever gets finished) The sprite glitch at the left is caused by a late write to COLUP1. I'm not sure if I can fix all the color glitches, because there's not enough time in horizontal blank to write to GRP0,GRP1,COLUP0,COLUP1 and COLUBK, is it? By the way, is it possible to use VDELPx in a single line kernel? I supposed that it's possible to update the pixels of P0 and P1 with a single write to GRP0 (or GRP1), but in my test, it didn't work as expected. Has this been done before? Edited July 6 by Lazycow 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted July 6 Share Posted July 6 1 hour ago, Lazycow said: The sprite glitch at the left is caused by a late write to COLUP1. I'm not sure if I can fix all the color glitches, because there's not enough time in horizontal blank to write to GRP0,GRP1,COLUP0,COLUP1 and COLUBK, is it? Not even close. But if you know where your sprite is located, you could update earlier (or later). 1 hour ago, Lazycow said: By the way, is it possible to use VDELPx in a single line kernel? I supposed that it's possible to update the pixels of P0 and P1 with a single write to GRP0 (or GRP1), but in my test, it didn't work as expected. Has this been done before? Yes, for sure. E.g. the 48 pixel kernel, mostly used for score display, has both VDELPx enabled to allow more register updates within a limited time. Quote Link to comment Share on other sites More sharing options...
Bomberman94 Posted July 8 Share Posted July 8 It's surprisingly good how close it comes to the c64 graphics - tubes and other items and there could be a game. 1 Quote Link to comment Share on other sites More sharing options...
Lazycow Posted July 23 Author Share Posted July 23 Update: gravity, background collision detection, scroll speed control The scrolling tries to always scroll a little bit ahead in viewing direction of the player. There're still some glitches, but I'll try to fix them later when the kernel is finished. @Bomberman94 Yes, but the current kernel cannot display tubes. But there could be rooms without horizontal scrolling. With more content... 11 Quote Link to comment Share on other sites More sharing options...
Lazycow Posted August 18 Author Share Posted August 18 Update: Player shots, enemy collision detection, explosions... 10 Quote Link to comment Share on other sites More sharing options...
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