+grafixbmp Posted February 11, 2011 Author Share Posted February 11, 2011 (edited) The screens for Marble Madness look great. The main issue I see is how to get the marble to go behind the playfield in certain parts of the map. This is going to require some complex sprite masking to make it look convincing. Normally isometric games draw the screen from the back to the front, so the masking is taken care of automatically. However, that is not an option when using the playfield. Crystal castles cheated and made sure that nothing was ever obscured Chris been long wondering about that. almost seems like there would need to be 3 masks or one that incorporates 3 things. platform mask, collision mask, and maybe a virtual mask that removes part of the ball when it is behind something. Only way I can thnik of for this is keeping the ball in ram and removing sections of the sprite as needed. The platform mask or whatever will also need slope data too. The floor is totaly open on this one. any ideas? Perhaps there could be a way for the ball to mask out player 0 since the ball is associated with the playfield? Edited February 11, 2011 by grafixbmp 1 Quote Link to comment Share on other sites More sharing options...
+grafixbmp Posted February 12, 2011 Author Share Posted February 12, 2011 Purhaps it could be done with the ball in conjunction with the span of the marble sprite. This area could be masked by a single byte that gets loaded and the bit that would set the playfield to player0 priority would get loaded from the byte in ram. And then after it is loaded it gets shifted down and used again the next scanline. 1 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 12, 2011 Share Posted February 12, 2011 Full beginner round added, with slower scrolling. Please inspect for mistakes-- I corrected a few, but comparing this to the original sometimes makes my eyes hurt. -John marble_2011_02_12.zip 2 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 Ok, one more update. Then, I need to put this away for awhile. Have fun! -John marble_2011_02_12_b.zip 1 Quote Link to comment Share on other sites More sharing options...
+grafixbmp Posted February 13, 2011 Author Share Posted February 13, 2011 Your brilliant man, simply brilliant. I was gonna share an animation but now im gonna wait a while. this is too cool. 1 Quote Link to comment Share on other sites More sharing options...
DracIsBack Posted February 13, 2011 Share Posted February 13, 2011 Simple scrolling added. No new screenshot, since when you scroll up, all you see is a solid screen. 7800 Arkanoid misses you ... 1 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 Momentum added to ball, and countdown timer added. 20 seconds, and then you need to hit reset. marble_2011_02_13.zip 1 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 Your brilliant man, simply brilliant. I was gonna share an animation but now im gonna wait a while. this is too cool. Just following your lead. I wouldn't have even thought this possible until you did those mockup screenshots. -John Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 7800 Arkanoid misses you ... Yeah, I miss it too. It's been over a year since I did any 6502 programming, so this was just an opportunity to get my feet wet again. -John Quote Link to comment Share on other sites More sharing options...
cd-w Posted February 13, 2011 Share Posted February 13, 2011 Yeah, I miss it too. It's been over a year since I did any 6502 programming, so this was just an opportunity to get my feet wet again. -John And Steam Tunnel Bob - that game was going nicely. Chris Quote Link to comment Share on other sites More sharing options...
+grafixbmp Posted February 13, 2011 Author Share Posted February 13, 2011 I guess I'll show what I did last night. The weird thing is the rate of movement for this new graphic would probably be odd just simply cause I rigged it to take the 8 pixel wide player graphic and by shifting its H position properly, make it seem like a 12 pixel wide graphic. This is just because of the the way it moves in the original games. 2 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 Now, THAT is really cool stuff. Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 (double post) Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 13, 2011 Share Posted February 13, 2011 A collection of thoughts. ==================== Collision-detection: ==================== I have a partially working collision-detection algorithm in place, but it needs help. So, the plan is to have 2-4 tables, each with 200 bytes in them. These correspond to the 200-byte high double-pixel beginner race. The player0 graphic has a VPos (0-199) and an HPos (16-136). The algorithm is as such: Take the VPos, put in X Load first collision table value at X (i.e. our current line). Compare to (HPos divided by 4). If we have a match, we're on a "bump", so take player's inertia and reverse it. Since we can have up to, say, 4 "bump" situations per line (for now, holes are represented by "bumps"), then we have 4 table-loads and checks, and we're good to go. Here's the dilemma. There are different actions to be taken when colliding. An easy example is if you're going southeast, and have a collision. That's simple-- you invert the inertia in both X and Y directions, and suddenly, you're bouncing backwards. Makes sense. However, there are other situations where you'll only want to invert inertia in either X or Y only. An easy example is if you're going northeast into a horizontal flat wall-- the logical direction of bounce is southeast. I'm not sure how I would differentiate these 2 scenarios. Anyone have any idea? ==================== Other thoughts about design ==================== Typically, as others note on this thread, I get to "almost the goal line", and then get bored or something comes up, and some of the stuff I make becomes temporary abandon-ware (with temporary maybe being a long time). So, I figure I need to set some goals for this thing. What I've set forth in my mind as a "fun to have" would be something that was releasable as a demo to show to the world that Yes, a Marble Madness game is possible. The Mega Man 2600 designer(s) only did 2 levels, and I thought that was staggering. For Marble Madness, I honestly have no idea how to make a 400-double-line level work, or even player 2 support work with the current kernel. And, I have no idea how to make your marble fall off-course or go "behind" things. So, I was thinking of it this way (here's what's achievable in my mind without much trouble): - Title screen "Marble Madness: (The Beginner Race)" - ability to choose 90 degree or 45 degree angle - The beginner race has a "win" condition when you cross the finish line. - Collision detection working pretty well. - Instead of falling off, you get bumped back. - Simple "beginner level" music. If I did it this way, it could be limited to 4K, and be a fun little thing for people to have. I also was thinking that if it got that far, it could be interesting to design a few "new" levels, each 200 double-bytes long. It could be a fun game, even so-- just a maze game, really based on Marble Madness. The contraptions like the green carpet, etc... would probably be scrapped initially, but still, there could be fun of the levels, which is kind of a "new twist" on the architecture. However, with that being said, I think a "Beginner Level" that's really functionally close to the original version is a great goal. Anyhoo, random thoughts. Regards, -John Quote Link to comment Share on other sites More sharing options...
Devin Posted February 13, 2011 Share Posted February 13, 2011 Very, very impressive! Quote Link to comment Share on other sites More sharing options...
+grafixbmp Posted February 13, 2011 Author Share Posted February 13, 2011 Yes, that awesome. This can easily set the stage for other isometric type games. I bet that with DPC+ even games like an isometric adventure game of any type could bee done too. 1 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 14, 2011 Share Posted February 14, 2011 Oh, I have an idea for my physics problem. So, we've got this table that says where there are places where you "bump". It looks something like this: CollisionTable ; Line 40 .dc.b 4 ; left of screen .dc.b 5 ; left of screen .dc.b 6 ; left of screen .dc.b 5 ; left of screen .dc.b 4 ; left of screen I was thinking about it-- the farthest it can go is to 43. That means it can go to 6 bits max. I have 2 bits I can do things with. Maybe what I need to do with those 2 bits is to use them. Maybe they can tell the direction of the "bump", i.e -, |, \, or /. With that information, I may be able to deduce what sort of bounce is needed. Would this be a good system? -John Quote Link to comment Share on other sites More sharing options...
+grafixbmp Posted February 14, 2011 Author Share Posted February 14, 2011 (edited) Sounds good to me. Not sure what the extra 2 bits could be used for. Only things I could figure out was, Lets say that any particular location has a rate of slope and that rate has an x and y offset for its direction. In this the x and y offset would be 45 degrees to the viewer (because of the isometric look) as "X" /=x \=y. I don't know if this truly could have any bearing but I had wondered about a single byte that tells everything the ball needs to know on how to move on the platform. just not sure what kind of data table it would be but I'm afraid it would be too big to be doable. one byte 1111111 separate 1111 = x axis: 1111 = y axis positive/negative values 1111 collision 1110 hole 1101 slope 6 power- 1100 slope 5 power- 1011 slope 4 power- 1010 slope 3 power- 1001 slope 2 power- 1000 slope 1 power- 0000 no slope 0001 slope 1 power+ 0010 slope 2 power+ 0011 slope 3 power+ 0100 slope 4 power+ 0101 slope 5 power+ 0110 slope 6 power+ 0111 goal this goes for both the x and y axis in an isometric view. This also gives 3 other conditions i just game some examples of what ifs. This was just an arbitrary thought though There could be a test for these first 01110111 = goal 11101110 = hole 11111111 = collision Don't read too much into this just thinking out loud. lol Edited February 14, 2011 by grafixbmp 1 Quote Link to comment Share on other sites More sharing options...
Atari Punk 78 Posted February 16, 2011 Share Posted February 16, 2011 Hey grafixbmp, look where your Mario ended up! I don't plan to leave this pic there and it's not going to be in the actual released hack, I just felt like taking a break and goofing off a bit... although, it would be a fun idea if someone were to replace all DD characters with Mario ones. Princess Toadstool as Linda. That would be a perfect fit. I wish some one would make a 32k version of Double Dragon with better graphics and two player mode for the 2600. I'd pay $45 for a good copy. Oh well, a man can dream can't he? 1 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 16, 2011 Share Posted February 16, 2011 Ok, quick update, tho no new release software for now. The good news is that I have gotten collision detection to be a lot better than I had it previously. In my first implementation, there were "gaps" where the ball could slip through-- and that seems to have been fixed now. The next step from here is to figure out some of the physics that need to happen upon collision. I have it so it always "reflects back" upon collision right now, but surprisingly, this behavior has a few rare situations where the ball itself can get stuck. So, that's the next step to work on. -John Quote Link to comment Share on other sites More sharing options...
Godzilla Posted February 16, 2011 Share Posted February 16, 2011 just amazing Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 17, 2011 Share Posted February 17, 2011 Ok, I need some testing help. I think I have a working method of collision detection. But, I'd like some people to verify that I haven't missed anything. At the moment, it's only 100% set up to work on the orange triangle on the left (see picture). By the way, the ball is now an "equal sign" that really is just showing the 4 corners that are tested for collisions. Basically, I want to know if anyone can get the equal sign to get stuck in the triangle area (either around its edge, or inside). 5 points to the person who can get it to happen. And 10 points to the person who can do it, and tell me how to reproduce it. Any takers? It's a boring task, I know, but I would like some verification before I put collision detection on more of the playfield. -John marble_2011_02_17.zip 1 Quote Link to comment Share on other sites More sharing options...
Godzilla Posted February 17, 2011 Share Posted February 17, 2011 trying... 1 Quote Link to comment Share on other sites More sharing options...
Godzilla Posted February 17, 2011 Share Posted February 17, 2011 (edited) X -X --X ---X ----X* -----X -----X -----X * is where I was able to get it stuck whilst coming up from below in a fast arc, with the downswing ending at that point. it would be a lot faster to check if the ball didn't bounce off like mad (and no timer,) or even just for the sake of collision testing, 1-1 movement on the ball to stick control... The feel of the movement is very good for marble madness, tho. Edited February 17, 2011 by Godzilla 1 Quote Link to comment Share on other sites More sharing options...
+Propane13 Posted February 17, 2011 Share Posted February 17, 2011 Ok, the 10 points are yours. I can make a "no time limit version" later in future tests; that should be easy enough. As for the bouncing-- well, that's the part that I need to keep enabled for now to make sure it bounces out correctly. Just to clarify-- did it really get stuck, or did it just bounce around and then find its way out again? It should theoretically bounce out, even if it jostles around a bit before doing so. I've seen it do that a little. But, if it really is stuck, I'll need to do some thinking, as to why it happened in that particular place. It's gotta be one of those cases where a bunch of conditions hit at the exact same time, and then I'll have to correct for it. -John Quote Link to comment Share on other sites More sharing options...
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