PacManPlus Posted July 12, 2008 Author Share Posted July 12, 2008 (edited) 1) Put a delay when the player's shot hits the 'ceiling' or an invader's shot 2) Allow for a selection of a 'color pallette' on the options screen 3) Put an 'invader shot delay' so they don't start firing immediately Did all three above. There *is* now a small delay when the player's and invader's shots hit (depending on which shot, or both, are cancelled out). It is the same delay as when the shot hits a shield, or the ceiling. It would take too many cycles to figure out where to put the small explosion graphic. IMO it's not worth the extra processing. Color Scheme 0 = Original Invaders (white invaders, red ufo, green player/shields). Color Scheme 1 = The overlay Trebor posted (Red on top, then going down: Orange, Yellow, Green, Teal) Color Scheme 2 = My original color set. Also, the High Score Screen is as follows: BOMB:X SHLD:X INVS:X ZIG:X Bomb: N=Normal, F=Fast, O=Off (Invader Bomb Speed) Shld: N=Normal, M=Moving, O=Off (Shields) Invis: Y=Yes, N=No (Invisible Invaders) Zig: Y=Yes, N=No (Zig Zag Invader Bombs) Please try the two-player options, let me know if there are any screen jumps or any other issues. Thanks! Edited July 24, 2008 by PacManPlus Quote Link to comment Share on other sites More sharing options...
A Sprite Posted July 12, 2008 Share Posted July 12, 2008 (edited) I'm not a mathematical thinker. Apologies, if I am not as exact in my analysis as the others here. Good: Atmosphere: I had my doubts about Space Invaders for the 7800. It's been ported to nearly system out there, and most are slow paced shoot outs that wear their age a little too proudly - the impact of the original is lost in the name of purity of translation. Aliens shuffle into view, a shot takes them out. Rinse. Repeat. You get your quarter's worth...if you were there when the Invaders first landed. Yours doesn't suffer from that fate. Changing the options around allows me to set up the experience I remember, even if it's accuracy is a little lacking. Placing the game variations up front just begs one to explore them all. Kudos. Bad: The aliens in my playthrough stopped firing past a certain point. I have no idea if it was the due to the amount on screen, or how low they decended, but every near invasion was followed by the aliens deciding on an honorable suicide. I got to wave 5. I've never seen it before. Just to be sure, I played the arcade game again, and was wiped out in the first wave, when the last two kazikame aliens practically machine gunned me to death after they wiped out my bases... Random: Would it be possible to set up a gameplay mode that randomly changes the rules every round? Edited July 12, 2008 by A Sprite Quote Link to comment Share on other sites More sharing options...
gdement Posted July 12, 2008 Share Posted July 12, 2008 Unfortunately, I don't have any color palettes left. When I set the 'Invisible Invader' option, I turn Palettes 2, 3, 4, and 5 to black. 0 and 1 are the score and UFO, respectively, and 6 and 7 are (the shields and player 1) and player 2, respectively. You could reuse palettes 0 and 1. Just put an interrupt in your DLL after the mother ship. In that interrupt you'd reassign the color values on palettes 0 and 1, so when they get referenced further down the screen they show up in a different color. Change it back afterwards (probably during VBLANK). The enemy shots will always be below the mother ship so they'd be a good choice for sharing palette 1. I suppose everything is below the score so anything could share palette 0. Interrupts could also be used to simulate an overlay effect - just redefine the affected palette at predetermined scanlines. Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 12, 2008 Share Posted July 12, 2008 (edited) Bad: The aliens in my playthrough stopped firing past a certain point. I have no idea if it was the due to the amount on screen, or how low they decended, but every near invasion was followed by the aliens deciding on an honorable suicide. I got to wave 5. I've never seen it before. Just to be sure, I played the arcade game again, and was wiped out in the first wave, when the last two kazikame aliens practically machine gunned me to death after they wiped out my bases... Random: Would it be possible to set up a gameplay mode that randomly changes the rules every round? Wow...Similar deal with my recent experience. I made it up to Level 5 with a score of 5070 with the 7800 version. Played the Arcade version of Space Invaders, and could not get past Level 1. Last alien made it the bottom. Bob, I honestly had not played the Arcade version in a while, but I see a big difference between it and your version. It concerns the speed in which the Invaders move and shoot. In the Arcade version, it is both faster overall respecting the Invaders movement and shooting, and faster in the rate of speed/momentum the Invaders gain as well as the frequency of that gain as they are eliminated. If possible, besides an option to change colors (IMHO), more importantly, perhaps there can be an option controlling the "speed" of the Invaders (I.E. Beginner, Normal, Arcade, Expert settings). Right now in order to come closer to imitating the Arcade expereince, the initial speed of the Invaders (When the game first starts) needs to be faster, as well as how frequently the Invaders pick up speed as they are eliminated. In your version, you can eliminate many Invaders without them picking up much speed respecting their "marching" and shooting. -Trebor Edited July 12, 2008 by Trebor Quote Link to comment Share on other sites More sharing options...
PacManPlus Posted July 12, 2008 Author Share Posted July 12, 2008 (edited) Ok, thanks all. I worked on the shot frequency. Only the remaining invader columns are now chosen to place a shot (instead of always all 11 columns). What I used to do was if a column was chosen and there were no invaders, the routine would exit. I thought it would give a little randomness to the shots. But toward the end of the round this would become an issue. This has been fixed. I have one bug, though. For some reason, every once in a while, at some point they stop firing completely. I can't find why this happens. Once I find this issue I will post another update. As far as the speed of the invaders, I may disagree with you here. They start to move at $37 frames between each invader, and reduce by 1 with each hit until that last invader moves at every frame. It is a linear reduction (starting at $37 = decimal 55 = the number of starting invaders). The original machine only moved one invader per frame, so it *has* to work out the same, unless the original machine didn't run at NTSC 30fps. I think maybe the issue with the absence of invader shots has something to do with this interpretation that they are moving slower. @gdement - Thanks for the information. (As you probably can tell) I'm not that familiar with interrupts. I will check that out. Edited July 12, 2008 by PacManPlus Quote Link to comment Share on other sites More sharing options...
NightSprinter Posted July 12, 2008 Share Posted July 12, 2008 Trebor, I'd have to quote Lrr from Futurama for this one: "Instead of shooting where I was, you should've shot at where I was GOING to be.. BWAHAHAHA!". Was an interesting little tip from that section of the "Anthology of Interest". Basically shoot one or two seconds before the last one gets to where you're at. I'm at a friend's house right now, Bob, but when I get home I'm definitely going to give the new version a shot. Quote Link to comment Share on other sites More sharing options...
ZylonBane Posted July 12, 2008 Share Posted July 12, 2008 (edited) I put together a little composite mockup of the arcade and 7800 versions, showing the left/right bounds of the player and invaders: As you can see, there are some alignment issues. Most significantly, the invaders are allowed to travel a lot more to the left and right (well, 10 pixels more total) in the 7800 version. Not only does this make them drop more slowly, it makes it easier for the player to shoot away the flanks. I also noticed that, strictly speaking, the middle invader type should be shifted 1 pixel to the right (they should be right-aligned with the big invaders, not left-aligned). And I really see now why most home ports move the status displays over to side of the screen. Keeping them at the top and bottom forces the gameplay area to be significantly compressed. Also, I had an idea about the ripple effect. Since implementing the full effect is proving too much of a PITA, would it be practical to just implement the sprite animation part of it? That is, still leave the invaders stationary while the movement timer counts down, but every tick, flip an invader over to its other image state. EDIT: Just tried out the latest ROM. Yay, color choices! Scheme 0: Something wrong here. The bottom area is brown instead of green. Scheme 1: Looks good. Scheme 2: Strangely, this one does have a properly green bottom area. The whole scheme is a bit odd, what with the top three rows starting out the same color. Personally, I'd recommend the green/blue/yellow palette instead. That way you wouldn't have two variations with the same-colored shields. Something I'm ambivalent about is whether the bottom text should be white or tinted. In all the MAME red/white/green overlays, the bottom text is white. But then in the other ones it's tinted along with everything else. I guess it comes down to authenticity vs aesthetics (both of which are debatable, oye!). Edited July 12, 2008 by ZylonBane Quote Link to comment Share on other sites More sharing options...
Shannon Posted July 12, 2008 Share Posted July 12, 2008 Keep up the good work pacman plus! Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 13, 2008 Share Posted July 13, 2008 Most significantly, the invaders are allowed to travel a lot more to the left and right (well, 10 pixels more total) in the 7800 version. Not only does this make them drop more slowly, it makes it easier for the player to shoot away the flanks...... Scheme 0: Something wrong here. The bottom area is brown instead of green. Scheme 1: Looks good. Scheme 2: Strangely, this one does have a properly green bottom area. ... The boundaries issue would lend to my perception respecting speed. Is it also why the "mother ship" along the top appears to be on screen longer in the 7800 than the Arcade too? I just took note of that is my last 7800 vs Arcade session. Adjusting the boundaries coupled with more accurate and consistent shooting from the Invaders should allow for more Arcade-like difficulty. Definitely, the shields/ship (bottom area) colors from Scheme 2 should replace Scheme 0 shields/ship colors. Did anyone else notice the couple of "garbage dashes" towards the upper left hand corner of the screen in the latest version? -Trebor Quote Link to comment Share on other sites More sharing options...
PacManPlus Posted July 13, 2008 Author Share Posted July 13, 2008 (edited) I found and fixed the issue of the invaders 'cease fire' once there are only a few left and they get closer to the bottom of the screen. Thanks Shannon, Lord Helmet for the compliments! As you can see, there are some alignment issues. Most significantly, the invaders are allowed to travel a lot more to the left and right (well, 10 pixels more total) in the 7800 version. Not only does this make them drop more slowly, it makes it easier for the player to shoot away the flanks. I have fixed this, but the 7800 moves screen objects in 2-pixel increments while in 320 mode. So I pulled the invaders in 2 pixels from the left, and 2 pixels from the right. I also noticed that, strictly speaking, the middle invader type should be shifted 1 pixel to the right (they should be right-aligned with the big invaders, not left-aligned). Done. Also, I had an idea about the ripple effect. Since implementing the full effect is proving too much of a PITA, would it be practical to just implement the sprite animation part of it? That is, still leave the invaders stationary while the movement timer counts down, but every tick, flip an invader over to its other image state. I actually don't think that would look good - I had something similar to that scenario happen by accident while I was trying to fix something else... It looks odd when the invaders move with no animation (which is what would happen here, until we get to that particular frame). Just tried out the latest ROM. Yay, color choices!Scheme 0: Something wrong here. The bottom area is brown instead of green. Scheme 1: Looks good. Scheme 2: Strangely, this one does have a properly green bottom area. The whole scheme is a bit odd, what with the top three rows starting out the same color. Personally, I'd recommend the green/blue/yellow palette instead. That way you wouldn't have two variations with the same-colored shields. Scheme 0: I was going by the actual hardware... (I really wish the colors would get fixed in the ProSystem emulator). The bottom area is green on the real hardware. Having said that, I did lighten the green color a bit, because it seemed a little dark. Scheme 1: Thank you Scheme 2: The bottom (on the real thing) actually is a 'teal' color (very similar to Scheme 1), but I changed it to what you suggested; I like a whole different set of colors for each Scheme Something I'm ambivalent about is whether the bottom text should be white or tinted. In all the MAME red/white/green overlays, the bottom text is white. But then in the other ones it's tinted along with everything else. I guess it comes down to authenticity vs aesthetics (both of which are debatable, oye!). You're right. I changed it back to white... That's my personal choice I'm thinking, any informational area (score, high score, lives, level) should be a single color but different than the others... (Again, OCD showing it's head) The boundaries issue would lend to my perception respecting speed. Is it also why the "mother ship" along the top appears to be on screen longer in the 7800 than the Arcade too? I just took note of that is my last 7800 vs Arcade session. Adjusting the boundaries coupled with more accurate and consistent shooting from the Invaders should allow for more Arcade-like difficulty. I've adjusted the boundaries of the UFO as well. It used to use the whole screen to travel accross, but now it's using just the area it's supposed to. Did anyone else notice the couple of "garbage dashes" towards the upper left hand corner of the screen in the latest version? I did not see this on the real thing here ... Please try this version and let me know if you still see any garbage. One thing I'm concerned about is the shield / player alignment. I took steps to make sure everything was centered in the playfield for the 7800 version, but in ZylonBane's screen shot it looks like the arcade version is not centered, but off to the left a little. I'd like to leave it centered, does anyone have issue with that? (It's very easy to change, this is just a personal preference) BTW, One final thing I have to not forget, is find a good routine to show a byte as decimal on the screen. Right now the level indicator shows the level in hex. Thanks for all the help, guys Bob Edited July 24, 2008 by PacManPlus Quote Link to comment Share on other sites More sharing options...
supercat Posted July 13, 2008 Share Posted July 13, 2008 I actually don't think that would look good - I had something similar to that scenario happen by accident while I was trying to fix something else... It looks odd when the invaders move with no animation (which is what would happen here, until we get to that particular frame). If the draw-able area of the invaders is wider than the drawn area, you might be able to have four versions of each invader shape: (0) Frame1 left, (1) frame2 right, (2) frame2 left, (3) frame1 right. Sprites would start out all in frame 0. Then ripple them through to frame 1. Then simultaneously reset them all to frame 2 while moving them right (this will have no visible effect). Then ripple them through to frame 3. Then reset them all to frame 0 while moving them right again. Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 13, 2008 Share Posted July 13, 2008 No garbage in this version, thanks Bob. I still think the "Teal-Green" should be the Green used in Scheme 0 for the bottom. Then again, we've danced this dance before with Inky...lol. Also, I still believe the Invaders shooting is a little on the slow side compared to the Arcade. Outside of that everything else looks great to me. Excellent work! Where's my cart?!?! -Trebor Quote Link to comment Share on other sites More sharing options...
PacManPlus Posted July 13, 2008 Author Share Posted July 13, 2008 (edited) No garbage in this version, thanks Bob. I still think the "Teal-Green" should be the Green used in Scheme 0 for the bottom. Then again, we've danced this dance before with Inky...lol. Also, I still believe the Invaders shooting is a little on the slow side compared to the Arcade. Outside of that everything else looks great to me. Excellent work! Where's my cart?!?! -Trebor We're not even using the 'Teal' anymore - I changed all of the colors for Scheme 2 to match (as closely as possible) the example that ZylonBane gave... Which Teal do you mean? BTW, thanks for the compliment @Supercat - thanks for the idea, but I ran out of room in the graphics area I don't have enough free space for another two sets of invaders each moved over a pixel. I fixed another two small bugs, will post another update soon. Edited July 13, 2008 by PacManPlus Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 14, 2008 Share Posted July 14, 2008 Which Teal do you mean? The Green/Teal used in Color Scheme 2 from the files attached to post number 151. That Green/Teal used for the ship and shields should be used in Color Scheme 0. I'll post screenshots later. -Trebor Quote Link to comment Share on other sites More sharing options...
PacManPlus Posted July 14, 2008 Author Share Posted July 14, 2008 Ok, thanks Trebor I've changed the color since then - please check the one attached to post 160 before you go any farther. Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 14, 2008 Share Posted July 14, 2008 (edited) Ok, thanks Trebor I've changed the color since then - please check the one attached to post 160 before you go any farther. Actually, I have and it doesn't match up. Unless I'm missing something I played the image posted in 160 prior to posting my previous comment. *EDIT: Just to make sure we're looking at the same colors/data: I am working off of ProSystem Emulator - Latest version (1.2) - Default Palette. Obtained here: https://home.comcast.net/~gscottstanton/ Here is how Color Scheme 0 appears in the most recent images (taken from post 160): Here is how I believe the shields and Player's ship should appear in Color Scheme 0 as taken from post 151 Color Scheme 2: -Trebor Edited July 14, 2008 by Trebor Quote Link to comment Share on other sites More sharing options...
PacManPlus Posted July 14, 2008 Author Share Posted July 14, 2008 (edited) Hey Trebor: I see what you mean, but the color in ProSystem is wrong. When I choose my colors, I use what I see on a real TV. The green used in Scheme 0 is the correct green on a real TV. When I get home, I will take a pic of the TV screen I REALLY hope in the next release of ProSystem the colors are fixed so that all of us can be sure of the colors we are seeing in the emulator. Thanks for the help. Bob Edited July 14, 2008 by PacManPlus Quote Link to comment Share on other sites More sharing options...
NE146 Posted July 14, 2008 Share Posted July 14, 2008 (edited) ok.. I've finally tried out this game for the FIRST time ever (been on vacation for the past 2 weeks). I played it on Shannon's updated 7800 emulator for the xbox. So far.. it looks good! Aside from the obvious differences in gameplay from the arcade which is expected and absolutely fine. For example in the very beginning between the 1st and 2nd barrier when you shoot up, you can shoot the 3rd & 4th column invaders (as opposed to the 2nd and 3rd in the original). But that's absolutely welcome I think.. it makes it unique. Everything looks real good upon a quick play I think the one quicky complaint I have is that the player's ship position isn't reset when a new round begins. So it changes things up a bit as far as initial round strategy. But that could be a welcome as well. Another thing I noticed was no Rainbow effect when the bottom type invader is the last on the screen.. that'd be a nice thing to put in I think Edited July 14, 2008 by NE146 Quote Link to comment Share on other sites More sharing options...
ZylonBane Posted July 14, 2008 Share Posted July 14, 2008 I REALLY hope in the next release of ProSystem the colors are fixed so that all of us can be sure of the colors we are seeing in the emulator. ProSystem supports custom palette files. Is there a more accurate one floating around out there anywhere? Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 14, 2008 Share Posted July 14, 2008 (edited) I REALLY hope in the next release of ProSystem the colors are fixed so that all of us can be sure of the colors we are seeing in the emulator. ProSystem supports custom palette files. Is there a more accurate one floating around out there anywhere? I'm at work right now, but there are at least a couple that can be used which are on my home computer: There are (At least) two from Nabuko78. There is one based off of the color palette work from Stella. And there may be one more. I'll post the palettes that i have later*. The problem is with all of them, there is "something off". No one palette has all the colors accurate. However, I do believe the latest palette from Nabuko comes the closet (To my knowledge). That one should also be the one that is currently utilized in MESS What we really need is a "blargg 7800 NTSC palette": http://www.slack.net/~ant/libs/ntsc.html Anyhow...don't want to diverge too far from the actual point of this discussion.... Bob, if you can post a TV capture that would be great...Otherwise, the color issue we can go back and forth on all day...It is especially pointless without an accurate palette being used in the emulators. *EDIT: Attached are three palettes zipped. From my understanding Nabuko78_20061224.pal [Latest palette from Nabuko] is the best available right now. ProSystemPalettes.zip -Trebor Edited July 14, 2008 by Trebor Quote Link to comment Share on other sites More sharing options...
Underball Posted July 14, 2008 Share Posted July 14, 2008 (edited) I REALLY hope in the next release of ProSystem the colors are fixed so that all of us can be sure of the colors we are seeing in the emulator. ProSystem supports custom palette files. Is there a more accurate one floating around out there anywhere? If you're using Prosystem version 1.2, it already has the latest Nabuko Palette as it's default. It's as close as anything has come to accurate yet. But it's still not perfect. Something the light blue/green/teal/light green part of the Prosystem pallete is messed up, as you can see from this and the color of Inky in Pac-Man Collection. I wish I knew which values to work on, I'd have already fixed it. Edited July 14, 2008 by Underball Quote Link to comment Share on other sites More sharing options...
CV Gus Posted July 14, 2008 Share Posted July 14, 2008 Reading through these posts, a (probably ridiculous) question occurred to me... Aside from sound, are there things a ColecoVision can do better than the 7800? Quote Link to comment Share on other sites More sharing options...
NE146 Posted July 14, 2008 Share Posted July 14, 2008 Reading through these posts, a (probably ridiculous) question occurred to me... Aside from sound, are there things a ColecoVision can do better than the 7800? Well.. it runs a "perfect" Space Invaders Quote Link to comment Share on other sites More sharing options...
Trebor Posted July 14, 2008 Share Posted July 14, 2008 (edited) If you're using Prosystem version 1.2, it already has the latest Nabuko Palette as it's default. It's as close as anything has come to accurate yet. But it's still not perfect. Something the light blue/green/teal/light green part of the Prosystem pallete is messed up, as you can see from this and the color of Inky in Pac-Man Collection. I wish I knew which values to work on, I'd have already fixed it. My bad...I forgot the 'Default' palette in ProSystem 1.2 is using Nabuko's latest palette. EDIT: Bob, are these colors correct? Scheme 0: Scheme 1: Scheme 2: And for Extra...Inky now Green-Blue/Blue-Green [Not just Green]: -Trebor Edited July 14, 2008 by Trebor Quote Link to comment Share on other sites More sharing options...
Underball Posted July 14, 2008 Share Posted July 14, 2008 Fixed it. here's the NEW Prosystem NTSC palette. Inky is now Blue again. I corrected the whole gradation, not just this particular color, so everything should look right/as close as can be. Prosystem_NTSC_Corrected.zip Quote Link to comment Share on other sites More sharing options...
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