15 replies to this topic

[peteym5]

http://www.atariage...._1#entry2350331

I have continued my work on an Adventure Type Game that uses a multicolored sprites with a player/missile multiplexer. This is a pre-concept demonstration to show others what the program is capable of doing. It also lets me see if eveything can be completed within a VBI cycle, how much flicker occurs with the sprites and what things may look like as I am developing the game. We know the Atari 8-bit only has an x-number of clock cycles within a frame to complete everything. I am testing it at the max of 8 sprites on the screen at once to show it can be done. However I am thinking that most of the rooms may normally have 4 to 6 sprites. I can create little zones for some monster types so that not too many crowd on one line. Right now there is not much logic in them, just random directional movements.

The Rooms are drawn with a series of instructions rather than being stored in memory as full screens. Doing that way allows almost 3 times as many rooms available. With a 128KB Max cartridge, probably store 256 rooms, along with lots space for sprites, sound effects, fonts, and other data. The Room Index is a byte, 8 bit, range of 0 to 256. Should handle most adventure type game designs. Would have to optimize the bank switching. I prefer to copy the program logic to ram when a cartridge is initialize so it just bank switches to access different portions of data. The multiplexer rountine needs to execute fast, so its best the sprite data come from one bank or copy some of it to ram.

I have not finialized on a design yet. Right now I am tweaking the routines. Looking at doing a simplified action RPG with hitpoints, experience, some skill levels, a few different weapons. Not going to get crazy with character attributes like Charisma, Dexterity, Wisdom, etc. I discovered doing games with those things on the PC slows down the pace by making the player worry about that stuff. I am also not a big fan of "turn-based" stuff.

[peteym5]

I did an update for this Room by Room Adventure / RPG engine I am developing. I am using it to experiment with different sprite multiplexer code and see how far I can get CPU usage down. I admit going with 8 multicolor sprites with the Atari 8-bit player missile graphics will flicker like crazy. This update has some of the monsters with different movements and I created some rooms to move around in. The limitations of how many rooms and sprite images is defined by amount of memory available. 64K machine can probably hold 200 sprite images with 64 rooms. 130XE or 128K Max Cart can go as far as 255 rooms.

This is the direction I would go if I wanted to progress the 2600 Adventure or Zelda like game on the Atari 8-bit. I wanted to make an adventure game with many rooms 20 years ago. I was limited to using Basic/Turbo Basic back then with a few ML routines I copied from a magazine, and was just learning assembly. Now Multiplexing and all assembly programming is bringing such a game to reality. I like mixing Semi Role Playing Game elements with lots of action. Have a character go around finding stuff and while advancing the character.

I made a 3D Role Playing Game engine on the PC, and been taking a break from it. Seems like not a whole lot of people want to invest in stuff on the PC unless its really good. Working with a simpler 2D system may give me a direction of where to go next with new programs. We all kinda have to take a step back before going forward.

Attached Files

•  ARPG.xex   29.83K   41 downloads

[peteym5]

Made some progress with this RPG engine over the last week. Made it so you now have to hit a monster several times before he die, testing multiple hitpoints. Added keys and program remembers if you already taken them as you enter the room. I am experimenting with the ideal of alternating between 2 antic 4 fonts to give the illusion of more colors. I understand if you did an alternating dither between frames, it looks like a 3rd color. The 2 colors have to close to the same lumance level also. Looks good with Altirra with frame blending turned on which resembles what it may look like on a real Atari. Remember, the vsync on the PC monitor is differant so if frame blending is off or if it ran on Atari800win, it is more appearant.

I still have to do some tests on an actual Atari when I have more of it completed. Since it is geared to work with RMT, it can use any piece of music and sound effects.

If you like what I am doing or have any suggestions what you want to see, please reply. I am looking to do 2 original titles myself and maybe work with other Atari Game Designers for a few more.

Attached Files

•  ARPG.xex   33.54K   67 downloads

Edited by peteym5, Sun Feb 19, 2012 12:40 AM.

[Bryan]

Looks nice! A lot of stuff going on.

[Heaven/TQA]

Pete... I can share Diablo-like engine, map generator and battle engine plus inventory plus upleveling code? ah... not to forget the item generator for more than 16384 different weapons and armors.

[Creature XL]

I underestimated the possibilities of PMG-multiplexer when I read the old threads from Heaven and others.
Looks promising. I hope I find the time to fool around with a multiplexor as well.

[Heaven/TQA]

na... 6 multiplexed PMs is not much...

[peteym5]

There are several ways of doing player/missile multiplexers on the Atari, One is VBI based using WYNC commands to reach a scan line before changing the registers. Issue there is that it ties up the CPU. The other method is with Display List Interupts and leaves the CPU free during most of the VBI. I manage to get up to 20 monocolored or 10 tricolored sprites at 20 pixels tall to move around within the VBI cycle. I am keeping it at 8 to help keep the flickering down. I am deleting the sprites when the scan lines reaches the last visible line and redraw them in their new positions at the start of the VBI cycle. Most programmers use techniques like self-modifying and unrolled code to speed up execution. If more than 4 sprites are on one line, one sits out each frame, alternating between which one

[Goochman]

Looks great from a color perspective. Maybe 1 or 2 fewer enemies to keep the flicker to a minimum

Initial thoughts on the engine were potential for Venture, Shamus, Lost Tomb(that pyramid game), and Rogue.

Since you have the room navigation element w/keys maybe you construct a story around needing to get through some fortress/castle/cave with rooms/puzzles/enemies that lead to some sort of boss type creature before moving to the next stage. Obviously final stage would have whomever you were looking to get rid of to capture whatever precious prize there is.

[peteym5]

Heaven/TQA, on Sun Feb 19, 2012 1:42 PM, said:

Pete... I can share Diablo-like engine, map generator and battle engine plus inventory plus upleveling code? ah... not to forget the item generator for more than 16384 different weapons and armors.

Heaven I am trying to send you a private message, but it says I cannot send it.

Goochman, on Mon Feb 20, 2012 8:32 AM, said:

Looks great from a color perspective. Maybe 1 or 2 fewer enemies to keep the flicker to a minimum

Initial thoughts on the engine were potential for Venture, Shamus, Lost Tomb(that pyramid game), and Rogue.

Since you have the room navigation element w/keys maybe you construct a story around needing to get through some fortress/castle/cave with rooms/puzzles/enemies that lead to some sort of boss type creature before moving to the next stage. Obviously final stage would have whomever you were looking to get rid of to capture whatever precious prize there is.

I am testing with 6 enemies to help optimize and debug the code. When I start building an actual game, I plan to have around 4. Maybe have the other available sprite represent an immobile item. The multiplexer rotates between 8 sprites, and which one it starts with is taken from the lower 3 bits of a clock that updates 1/60 (1/50Pal) per second. Right now I am putting together some routines that I can make several adventure like games. I am thinking about multiple boss creatures where you have to get multiple prizes.

I may do a random item placement setup where even after one solves the game, they can play the game with this option, but not know where things are. Similar to 2600 Adventure option 3. Have it set it up so like keys don't end up beyond the doors they have to unlock.

[peteym5]

Here is the next update. I have a couple of treasures inside the map, along with scrolls, and potions. Right now I just threw together a quick map with monsters in each room for test data. This helps debug the programming and see how things work together. I discovered what I am doing to increase background colors is known as SuperIRG.

I am doing this as a pre-concept demonstration to show others what a game may look like and how it works. It just has a few basic core functions. It is not really a whole game or final version. It is useful to get some feedback from people before actually designing a final game with these routines. I do know SuperIRG mode does not work great with emulation. I am considering making several games off of a set of core routines. Maybe one small freeware game and several 128k cart. Something that uses extended ram banks is also being considered. Anybody want a 512k game?

Attached Files

•  ARPG.xex   34.27K   38 downloads

[peteym5]

Have more stuff working now. Many of the screens only have 5 monsters instead of 6 so it does not appear to flicker as bad. I added the ability to use that extra monster sprite as an item the character can get. Can have a tunnel exit in the middle of the room, if your character touches it, it will send you to another screen. Tested a few locked doors where you have to get a key to go beyond a point in the game. I am creating some central core routines for this engine and trying not to do anything specific for a game. What I am looking to do is make a series of games spun from a common set of ML routines to save time. Anyone can customize these routines to suit their needs.

I hope to get some attention and stir up some interest for a top-down view Role Playing Game on the Atari. I understand there have not been too many good RPG and Adventure Games done on Atari 8-bit systems. The programming is derived what I did for Venture, but greatly altered them for multicolored sprites and room by room navigation. The map navigation works similar to games like 2600 Adventure or the first NES Legend of Zelda. I did not want to do anything scrolling. My partner in doing Atari 8-games asked about using that Atari Wolfenstein3D engine for a RPG, but that looks like too much work for one person. It took me a lot of work to do something similar on the PC using Visual Basic. To do it on the Atari 8-bit in assembly is crazy for one person.

I do need some feed back on how this looks. I did a test on Atari Actual Hardware and I do say things like flicker or using SuperIRG is less noticeable. That is because emulating on the PC does not match up frame rates and no emulator truly has the same appearance as actual hardware.

Attached Files

•  ARPG_V3.xex   34.72K   66 downloads

[Goochman]

Peteym5 - take a look at this enhanced version of Venture:
http://www.atariage....venture-remake/

It introduces some interesting enhancements like up and down stairs to go about the dungeon and some 'traps' in rooms.

[Tin_Lunchbox]

In my opinion it looks very cool. Those are interesting-looking "enemies," from the lion to the cloud to the spaceman. Yeah, the flickering is pretty bad, but then will the final game actually require so many in one room?

It reminds me somewhat of Nolan Bushnell's "Secret Quest" for the 2600/VCS.

[peteym5]

I am aware of that enhanced version of Venture. I did incorporate a few enhanced features that will soon be released from Video61. Has a standard version that looks and plays very similar to Coleco version and a Challenger Mode. I tried to make this game compatible with the majority of Atari 8-Bit computers so I had limits of how far I could go with it.

This RPG Demo was derived from some the programming I used for Venture. I built something that went room to room like the 2600 Adventure and switched to using multicolored sprites.

The subject of doing Mouse Trap did come up, but I did not jump on it. Mouse Trap has similarities to PAC-MAN and I remember there were a lot of PAC-MAN clones on competing systems back in the early 80s. There was another one called Ladybug.

[tjb]

Wow, that's pretty impressive! Keep up the great work! I'd love to see a new game along the lines of Galahad and the Holy Grail...

tjb