adamantyr

Also, I recently moved my blog to Wordpress, after Blogspot decided not to support FTP publishing anymore. Like I'd trust Google's servers now... the reason they got hacked was they didn't bother to upgrade past IE6 and an older version of Adobe on their servers. And the hackers KNEW it and wrote a zero-day hack to deliberately target them. The target controls are going to be really a bother to code and debug. I think I'm in the home stretch; I just need to do the actual controls for moving the cursor about or scrolling a menu. As a bonus, I get the item/spell handling for travel for free, since it and combat use the same system. Adamantyr

(Copied and reposted from Homebrew Discussions, now that we have a 99'ers board on Atari Age) Greetings all. I decided I should make a semi-permanent topic about my ongoing project. Some lengthy background... While finishing my C.S. degree in college, I was overwhelmed with a desire to dig out my old computer from the basement and fire it up again. The old hardware actually still worked, although I had to get the keyboard replaced. The old membrane-driven keyboards decay over time. The mechanical in there now that should outlast the silicon. After playing around with it for awhile, and finding some great resources on the web I completely lacked in the old days, I decided I wanted to do some vintage assembly projects. Why? Well, I blame the fact I hadn't programmed in ten years, and that hobby-wise, I was still back there, a 13-17 year old, desiring to write a game but lacking the skills, patience, and knowledge to do so. My first project was to convert a game written in BASIC to pure assembly. I learned a lot about the process by doing so, and I was amazed that the complete assembly program was only about 5k, roughly half the size of the BASIC listing. And WAY faster. My second project, which is incomplete, was to covert the famous "Eastern Front: 1941" game for the Atari 8-bit home computers to my TI. I got the bemused permission from Chris Crawford himself to do so. (He remarked that the project was rather quixotic.) I had a complete listing of the program in 6502 assembly, with a few comments thrown in. I got a decent amount of the way into it before stopping. Part of the problem was it just wasn't that fun converting someone else's work. The other was trying to understand how the A.I. worked was maddening from the assembly perspective... and I realized I could never be certain I had captured the original game play or not. I may go back and finish this one later. Having decided to set out on my own original project instead, it was a quick decision as to what I wanted to make: a disk-based CRPG. The TI-99/4a lacked a great deal of the more sophisticated software of other computers of its time, because very few 99'ers owned disk systems when it was still actively supported. Complicating matters was the unique assembly language it had. Unlike the Apple, Commodore, and Atari systems which all had 6502 chips, porting programs was much more difficult. So all of the CRPG greats like Wizardry, Ultima, Might & Magic, were nowhere to be found on the TI... it had a very good dungeon crawler called Tunnels of Doom, but that was it. A later developer created a decent clone of Phantasie called Legends, but it ran in Extended BASIC and was rather small-scale, about comparable to Ultima I in scope and complexity. Anyway, it's been five years since I started... the project's been interrupted by job hunting, loss of interest, emulator problems, design issues, and so forth. I'm fired back up recently thanks to a brisk emulation development curve, but work slowed me down a bit... I'm presently working on the combat engine controls, a terrible task I've put off for far too long. Feel free to read up on my efforts, and offer your comments and criticisms. (The two I usually hear are "why in assembly?" and "why waste time on a vintage system?") Preliminary title screen First project: TI Trek Second project: Eastern Front 1941 CRPG Page (updated seldomly) Ongoing Development Blog Adamantyr

Greetings all. I decided I should make a semi-permanent topic about my ongoing project. Some lengthy background... While finishing my C.S. degree in college, I was overwhelmed with a desire to dig out my old computer from the basement and fire it up again. The old hardware actually still worked, although I had to get the keyboard replaced. The old membrane-driven keyboards decay over time. The mechanical in there now that should outlast the silicon. After playing around with it for awhile, and finding some great resources on the web I completely lacked in the old days, I decided I wanted to do some vintage assembly projects. Why? Well, I blame the fact I hadn't programmed in ten years, and that hobby-wise, I was still back there, a 13-17 year old, desiring to write a game but lacking the skills, patience, and knowledge to do so. My first project was to convert a game written in BASIC to pure assembly. I learned a lot about the process by doing so, and I was amazed that the complete assembly program was only about 5k, roughly half the size of the BASIC listing. And WAY faster. My second project, which is incomplete, was to covert the famous "Eastern Front: 1941" game for the Atari 8-bit home computers to my TI. I got the bemused permission from Chris Crawford himself to do so. (He remarked that the project was rather quixotic.) I had a complete listing of the program in 6502 assembly, with a few comments thrown in. I got a decent amount of the way into it before stopping. Part of the problem was it just wasn't that fun converting someone else's work. The other was trying to understand how the A.I. worked was maddening from the assembly perspective... and I realized I could never be certain I had captured the original game play or not. I may go back and finish this one later. Having decided to set out on my own original project instead, it was a quick decision as to what I wanted to make: a disk-based CRPG. The TI-99/4a lacked a great deal of the more sophisticated software of other computers of its time, because very few 99'ers owned disk systems when it was still actively supported. Complicating matters was the unique assembly language it had. Unlike the Apple, Commodore, and Atari systems which all had 6502 chips, porting programs was much more difficult. So all of the CRPG greats like Wizardry, Ultima, Might & Magic, were nowhere to be found on the TI... it had a very good dungeon crawler called Tunnels of Doom, but that was it. A later developer created a decent clone of Phantasie called Legends, but it ran in Extended BASIC and was rather small-scale, about comparable to Ultima I in scope and complexity. Anyway, it's been 4-5 years since I started... the project's been interrupted by job hunting, loss of interest, emulator problems, design issues, and so forth. I'm fired back up recently thanks to a brisk emulation development curve, and I hope to push on and complete the combat engine by the end of the year. Feel free to read up on my efforts, and offer your comments and criticisms. (The two I usually hear are "why in assembly?" and "why waste time on a vintage system?") Preliminary title screen First project: TI Trek Second project: Eastern Front 1941 CRPG Page (updated seldomly) Ongoing Development Blog Adamantyr

Go ahead and put me down on the pre-order list too. Incidentally, sound in Classic99 is definitely broken, except for basic tones. I've talked to Tursi about this; his sound core is in need of a radical redesign. If you use TI99Dir, you can copy your files into a disk image and run it on MESS instead, which has full sound capability. Adamantyr

Going slow... got a new great job that's keeping me busy, and been doing a lot of online gaming with my brother and sis-in-law, so I have been a bit off task. My present plan is to have the skeletal combat engine (rich features disabled, basic combat flow) written up in a stand-alone framework by year's end, so that I can start filling it out and figuring out how much I can do in the limited memory area. I won't deny one fear of mine that's kept me from progressing is running out of RAM and having to make serious cuts or do something drastic, like page in code from disk. (Not fun, horrible to maintain due to static addressing issues, and a logistical mess.)

That's interesting... If you don't change the VDP registers to move the sprite tables into appropriate places, it's very possible to end up with overlap situations. A particular sore point with the TI-99/4a sprite implementation is their "auto-motion" system is dependent upon the sprite attribute tables being located in a fixed point of video memory... in order to have auto-motion in any form of graphics 2 mode you have to re-write the auto-motion routine as a user interrupt instead of relying on the ROM version. Still, this sounds like a case where the video chip emulation was more simulation, I.E. designed to expect only the most common cases, rather than virtually emulate the chip's entire behavior. There's a simulator for the TI, Win994a, that works pretty well, but with my graphics 2 mode programming has had some oddball side-effects. Good to know, though, that there's some pitfalls with it. I was considering the idea of doing a conversion of my CRPG to Z80 assembly so it could be potentially executed on a MSX1 system. When the TI version's finished, of course.

Yeah, the lack of colors has been bugging me with my CRPG design on the TI-99/4a. I've had to use some odd combinations (magenta for cliffs, dark yellow for wood) in order to keep a pleasing mix. Still looks rather muddy in NTSC, though. Fifteen colors is low, especially compared to the NES, and the lack of flexibility isn't cool either, but for the era it was produced in, this was the norm. Nobody could justify spending money on palette registers until the mid-80's. Heck, the TMS9918a at least could display all 15 at once with no restrictions in all modes except text mode. The Apple II had four, II+ had six, and the Atari 8-bit/Tandy Color Computer squeezed out four (white, black, red, blue) through color artifacting. One way you can reduce the memory footprint of bit-map mode on the TMS9918a is to use address masking in the video registers to reduce the number of tables. The screen is hard-divided into three regions of 256 characters apiece (32x8), and you can reduce this to two or even one table is you want. This lets you have the color depth of bitmap but with a display more like normal graphics mode, and only for 4k. (2k for patterns, 2k for color). Yeah, you're not doing high-res line graphics, but the TMS9918a is not the best chip for that sort of work anyway.

The TI users group on Yahoo is pretty active. More active than some other retro-computer groups I've seen. For my own part, I've been working on a vintage CRPG styled after Ultima, Phantasie, The Magic Candle, etc., exclusively for the TI. I have a blog and an article website up for it at the following URL's: Development Blog: http://www.adamantyr.com/ Article Site: http://www.adamantyr.com/crpg Not sure when it will be done, since I work on it on hobby time, and real life interferes quite a bit. Going to shoot to have it done by the end of the year, though. Adamantyr