+Karl G Posted August 26, 2020 Share Posted August 26, 2020 4 hours ago, Thomas Jentzsch said: One could omit PF0 (which would look pretty odd then with the striped background) and save 14 cycles/scanline. And/or use two-line sprites and save 11 cycles/scanline. Maybe then it becomes feasible. But the overall conclusion is that you cannot replicate the Zeviouz kernel even theoretically using pure 6507 assembler. Interesting. I think a Zeviouz-style background with two-line sprites wouldn't be a bad trade-off if someone wanted to attempt a non-ARM game done in a similar style, though. Quote Link to comment Share on other sites More sharing options...
+Andrew Davie Posted August 26, 2020 Share Posted August 26, 2020 5 hours ago, Thomas Jentzsch said: Displaying a sprite using e.g. MaskedDraw requires 11 cycles, that results into 22 cycles for both sprites. You could use extra RAM here, and have a 256 byte array for each sprite, with the sprite shape. Then the sprites code would be lda sprite1shape,y sta GRP0 lda sprite2shape,y sta GRP1 That would be 14 cycles, I think, to do both sprites. You could alternate scanlines for colour writes/shape writes, and have multicolour sprites, 14 cycles/ilne, 2 line resolution. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted August 26, 2020 Share Posted August 26, 2020 5 hours ago, Andrew Davie said: You could use extra RAM here, and have a 256 byte array for each sprite, with the sprite shape. That would work, but it would require a lot of RAM and quite a lot of CPU time for moving the sprite data while scrolling. Quote Link to comment Share on other sites More sharing options...
cd-w Posted August 26, 2020 Author Share Posted August 26, 2020 11 hours ago, Thomas Jentzsch said: But the overall conclusion is that you cannot replicate the Zeviouz kernel even theoretically using pure 6507 assembler. If the kernel is executed from RAM then self-modifying code could be used to achieve the same effect in pure 6507. This would require a lot of RAM for a full screen display, and the cost of all the writes would be prohibitive. However, if DCP/DPC+ is permitted then I believe it becomes feasible with pure 6507 assembler? For me, I'm comfortable using CDFJ and other techniques(e.g. bus stuffing) to push the TIA to the limit Chris 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted August 26, 2020 Share Posted August 26, 2020 37 minutes ago, cd-w said: If the kernel is executed from RAM then self-modifying code could be used to achieve the same effect in pure 6507. That was part of my calculation above already. I suppose you think about a fully unrolled kernel which runs from RAM. That might work, but is far off the original hardware too. 37 minutes ago, cd-w said: This would require a lot of RAM for a full screen display, and the cost of all the writes would be prohibitive. However, if DCP/DPC+ is permitted then I believe it becomes feasible with pure 6507 assembler? I think DPC is not fast enough too. But I am no expert here. 37 minutes ago, cd-w said: For me, I'm comfortable using CDFJ and other techniques(e.g. bus stuffing) to push the TIA to the limit Sure, no problem with that. I was just checking the limits of the original hardware. Quote Link to comment Share on other sites More sharing options...
rhuneke Posted August 29, 2020 Share Posted August 29, 2020 I can't select difficulty level. Only Intermediate is available. Is this option not yet enabled??? Quote Link to comment Share on other sites More sharing options...
+Karl G Posted August 29, 2020 Share Posted August 29, 2020 10 hours ago, rhuneke said: I can't select difficulty level. Only Intermediate is available. Is this option not yet enabled??? It works for me. Use the select switch to change the mode. Quote Link to comment Share on other sites More sharing options...
Fungi Posted August 30, 2020 Share Posted August 30, 2020 And just like the real thing, I've got a serious case of "Stairway to Heaven" optical illusion right now. Quote Link to comment Share on other sites More sharing options...
e1will Posted December 13, 2020 Share Posted December 13, 2020 I finally had a chance to download and play this. What amazing work! I love this. This was one of my favorite games in college and you've captured the feel of it so well. I look forward to seeing the mothership! 2 Quote Link to comment Share on other sites More sharing options...
eegad Posted December 27, 2020 Share Posted December 27, 2020 I just finally played this via Harmony cart and just wanted to say how impressed I was.... I can't believe you were able to do such a faithful recreation on the 2600. 1 Quote Link to comment Share on other sites More sharing options...
Bomberman94 Posted January 11, 2021 Share Posted January 11, 2021 Any news/updates about this? I‘m very excited about a PAL60 version and the other things you mentioned at the beginning ? Quote Link to comment Share on other sites More sharing options...
Inky Posted January 17, 2021 Share Posted January 17, 2021 This is unbelievably amazing! 2 Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted February 5, 2021 Share Posted February 5, 2021 @cd-w - FYI 6 Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted February 14, 2021 Share Posted February 14, 2021 I'm playing this via harmony on my 7800 using edladdins Seagull adapter for using genesis controllers. it only detects 1 button and checked it with my 7800 Xevios cart and two button works there with difficulty switch set to different setting. I look for my prolines and see if will detect two buttons and get back to on it Quote Link to comment Share on other sites More sharing options...
BrianC Posted February 15, 2021 Share Posted February 15, 2021 5 hours ago, Dan Iacovelli said: I'm playing this via harmony on my 7800 using edladdins Seagull adapter for using genesis controllers. it only detects 1 button and checked it with my 7800 Xevios cart and two button works there with difficulty switch set to different setting. I look for my prolines and see if will detect two buttons and get back to on it Did you try using the Genesis controller on the 2600 without the adapter? The adapter is used to make the Genesis controller work like a 7800 controller, but I heard that it's not possible for the 7800 controller's second button to work in 2600 mode? Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted February 15, 2021 Share Posted February 15, 2021 6 minutes ago, BrianC said: Did you try using the Genesis controller on the 2600 without the adapter? The adapter is used to make the Genesis controller work like a 7800 controller, but I heard that it's not possible for the 7800 controller's second button to work in 2600 mode? I'll have to dig out my 2600 and try then thanks Quote Link to comment Share on other sites More sharing options...
+Pat Brady Posted February 15, 2021 Share Posted February 15, 2021 32 minutes ago, Dan Iacovelli said: I'll have to dig out my 2600 and try then thanks It should work on the 7800. Just plug the Genesis controller directly into the 7800. Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted February 15, 2021 Share Posted February 15, 2021 Just now, Pat Brady said: It should work on the 7800. Just plug the Genesis controller directly into the 7800. I'll try that too ty Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted February 17, 2021 Share Posted February 17, 2021 ok I tired with just controller plugged into the 7800 still nothing. and tried my 2600 but it isn't working. also when just put the genesis controller in makes the harmony cart menu go crazy when I plug it in with edladdin seagull menu works normal. I'll figure something out for the first round of harmony games for the bonus game (ports are in the bonus games this year,orignal games play as normal games) Quote Link to comment Share on other sites More sharing options...
DragonGrafx-16 Posted February 17, 2021 Share Posted February 17, 2021 wow I never thought I'd see an actual vertical scrolling shmup on the 2600. Quote Link to comment Share on other sites More sharing options...
+Karl G Posted February 18, 2021 Share Posted February 18, 2021 3 hours ago, Dan Iacovelli said: also when just put the genesis controller in makes the harmony cart menu go crazy You need to hold down the B button when powering on the console to have Harmony detect the Genesis controller. Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted February 18, 2021 Share Posted February 18, 2021 20 hours ago, Karl G said: You need to hold down the B button when powering on the console to have Harmony detect the Genesis controller. ok will check that out Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted February 20, 2021 Share Posted February 20, 2021 @Karl G Thanks for the tip it was exactly that with the button on harmony cart. now I know the setting for Bonus game in round 1 of harmony games that I mentioned ZPH last night 1 Quote Link to comment Share on other sites More sharing options...
Dan Iacovelli Posted March 8, 2021 Share Posted March 8, 2021 2021 Harmony Games have begun bonus(Ports) we are using the current rom,if any updates happen during this round we will use that 1 Quote Link to comment Share on other sites More sharing options...
+ZeroPage Homebrew Posted March 16, 2021 Share Posted March 16, 2021 (edited) ZeroPage Homebrew is playing ZEVIOUZ for a high score in the Harmony Games on tomorrow's (Tue Mar 16, 2021) stream LIVE on Twitch at 6PM PT | 9PM ET | 2AM GMT! Hope everyone can watch! ZPH Twitch Stream: https://www.twitch.tv/zeropagehomebrew/ Games: Slide Boy in Maze Land (2021 Final Binary) by Vladimir Zuñiga @vhzc Hunger Shark (2014) by Anthony Luna @RetroFiends Zeviouz (2021 WIP) by Chris Walton @cd-w and Nathan Strum @Nathan Strum (Graphics) (For Harmony Games) (SET VIDEO TO 1080P60 FOR FULL QUALITY) Edited March 18, 2021 by ZeroPage Homebrew Quote Link to comment Share on other sites More sharing options...
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