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Tursi, that is uncalled for.

 

I mentioned other contemporary basics and graphics hardware, because they were explicitly called out as not being 4bit color supporting. The one seeking the award here is not me, I just want a 16 color mode for sprites and tiles, which ecm3 is not.

 

Why is this so hard?

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5 hours ago, wierd_w said:

Tursi, that is uncalled for.

 

I mentioned other contemporary basics and graphics hardware, because they were explicitly called out as not being 4bit color supporting. The one seeking the award here is not me, I just want a 16 color mode for sprites and tiles, which ecm3 is not.

 

Why is this so hard?

I'll give you my why just in case this is a misunderstanding, but then I'm done with it. It's not my fight.

 

Because three reasons from my point of view: they weren't contemporary, you were comparing apples to oranges, and it seemed you were moving the goalposts. Perhaps it is a communication issue. Contemporary was 1979 when the VDP hit the shelves, not 2 or 4 years later. Technology moved very quickly back then, and 3 years showed huge changes in capability. The sprite functions shouldn't be compared to backgrounds layers. And we jumped from drawing sprites to entire bitmapped displays, somehow. Again, my perception.

 

My stance is that you have the tools to do what you are asking for, and you seem to be saying it's not so because it's not the WAY you want to do it. You asked for 16 color sprites. If you overlay 2 8-color sprites, you get 14 usable colors, which is close. You can have three. But if you did two for every sprite in the game you would still have 16 moving objects available without any tricks. If you draw on the fat bitmap layer instead of using sprites, you get your 15 colors plus transparent (and this is as close to the EGA example as it gets right now, and still an independent layer). So you can even do that. I was hoping my advice would help you see your goal is closer than you think.

 

I prefer to come at the hardware, and see how close I can get to my goal, and I see your requests as pretty doable. It's frustrating that your response appears to be "heck no, I want the hardware changed". To me, and this may be just me, that's a strange way to approach a retro system. Am I misinterpreting?

 

But perhaps most importantly - what's the point of trying to convince me? I don't have any say anyway. You had your say and I had mine, why can't we just leave it at that?

 

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Probably miscommunication, yeah.

 

I stated "high end color graphics", and have never once stated that the systems I mentioned supported hardware sprites. (I went out of my way to say that they did not in fact.) this requirement is one you have insisted on.

 

The argument that this needs to be in the same class of system as the original VDP, (aside from hardware sprites, and back compatibility) is artificial; the reasons for the VDP's restrictions at the time of its manufacture were practical ones-- Cost of silicon was absurd, and they were making a home computer.  Today, this is not the case.  The restrictions are the functional ones of running out of vram (which can be addressed in various ways), and the width of the data bus connection to the vdp (which is not.) The requested color range is within the 6 bits addressing limit, and there was already talk about adding more vram on the MK2.  Given those conditions, why make such a stink over the request?  Especially when the designer has expressed disfavor that "nobody is using the features."  It is my position that if you give a mode that allows for a sensible palette, that people will use it.  It is less "I always want more colors!",  as it is "Hey uhm-- Unless you want bright, single color sprites-- you need to give a palette mode that people can actually work with without running into technical problems deep into development, where one set of sprites takes one pair of palettes, and another set has to reassign those palettes different ways-- So, can you give me a mode that can do that? The bare minimum for that is 16 colors in the palette. 32 will give you very nice results, and should be enough for anyone."

 

I have been trying to express that the current restrictions on using the VDP modes, even in the F18A, make it impossible to create a shaded general purpose palette. (which is what I really, earnestly need to avoid the kinds of problems stated.) I stated that I can do that if you give me 16 colors, but just barely.  ECM3 mode with layered sprites is not equivalent.  Matt's statement about vram makes sense if the full VDP memory space is available to the system, but that is not explicitly necessary for the VDP to do what it does.  "ECM4" could use banked internal memory instead, and get around that issue. The real limit is the number address lines used, which is hard-set at 6bits due to that many being how many are on the chip socket.

 

As for why I need the full 16 colors, If I do not have access to all my colors, it will result in garish results as tiles that need certain colors will not be able to get them. (For each color, there is an exponential function of color combinations that are possible. With the palette restrictions as is, this is not achievable. This is why it is not equivalent, like you assert.) If the intention is to get away from "Blocky" graphics, (which anyone can do), these restrictions make doing such work impossible, or at least, very unpleasant and unrewarding. (which is why few if any people are willing to do the work*.) I would conjecture that a good reason why nobody has been using these modes, is due to these restrictions.  These restrictions strike me as capriciously artificial (such as arguments about contemporaryness), so why the animosity to the suggestion to move beyond them, with a chip that is intended to move beyond them, (within the limits of feasibility)?  As long as it still operates in a back-compatible setting, there should be no problem. Why is this even a point of contention in the first place?

 

*It is one thing to say "Look, we have NES era color and sprite capability!"-- Yes, this is true.  However, the current crop of artists and other game makers have access to systems with 24bit RGB color with 8bit alpha blending, 3D vertex processing, and a raft of other things. Getting them excited over capriciously artificial restrictions makes about as much sense as asserting "We have addition! YAY!" when there are systems with built in vector math processors competing for talent.  This is why I mentioned it as an allegory previously.  To get a sprite artist excited, you need to give them what is these days considered the bare minimum to draw interest. 3BPP is not that thing. The technical bare minimum for that is 16 colors, with EXACTLY that many colors. (no, 2 less because of forced transparency does not work any more than losing some bits does for floating point math.)

 

From my perspective, I am asking "Hey, can I have the bare minimum needed to make awesome stuff for this platform?"

 

To which the answer has been a combination of "HISS!! HERETIC!", and "You can already do that-- (I wont listen to you why you can't)"

 

Essentially.

 

 

That kind of stonewalling is very unappealing and is very off-putting. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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2 hours ago, wierd_w said:

The requested color range is within the 6 bits addressing limit, and there was already talk about adding more vram on the MK2.  Given those conditions, why make such a stink over the request?

 

There seem to be some technical limitations that Matthew has already highlighted which get in the way of simply extending the number of bits assigned to palette vs number of bits assigned to the pattern. I've pasted the relevant reply below:

On 10/3/2019 at 8:46 PM, matthew180 said:

The other problem is technical.  From a hardware perspective I can't add 5bpp and skip 4bpp, so this would be two more color *modes* (depths) to support.  I don't know if there is enough time to access the additional pattern bytes, per tile, to support more bits per pixel (scan line time *is* limited).  It also means wider multiplexers for the data and addresses to VRAM, which consumes more FPGA resources, and I'm already at 95% utilization for the original F18A's FPGA.

 

I'm not disputing that having a fully and freely selectable palette of 16 colors anywhere on the screen would greatly help you , I'm convinced it is a whole lot more comfortable for you to work with less limitations and not more.

2 hours ago, wierd_w said:

... the current crop of artists and other game makers have access to systems with 24bit RGB color with 8bit alpha blending, 3D vertex processing, and a raft of other things. Getting them excited over capriciously artificial restrictions makes about as much sense as asserting "We have addition! YAY!" when there are systems with built in vector math processors competing for talent.  This is why I mentioned it as an allegory previously.  To get a sprite artist excited, you need to give them what is these days considered the bare minimum to draw interest. 3BPP is not that thing. The technical bare minimum for that is 16 colors, with EXACTLY that many colors. (no, 2 less because of forced transparency does not work any more than losing some bits does for floating point math.)

but I wouldn't go so far as to say this is how all - or even most - pixel artists feel. If I can make an analogy from my perspective as a coder, I actually enjoy the period-correct limitations quite a bit. I have very little interest in programming modern machines these days because there are so many tools out there that make it so much easier to create impressive looking results. The limitations of the TI99/4A provide challenges that are fun to try and overcome, and I have a much bigger sense of accomplishment whenever I've managed to do something that works around the limitations of the hardware.

 

I wholeheartedly and 100% understand that not everyone feels that way, and I'm absolutely not judging those who don't. Just wanted to point out that not everyone has the same reasons for enjoying this retro computing thing.

 

Having said that, just like everyone else I have some ideas regarding new features for the F18Amk2. I've always been a big fan of the way the Sega Master System handled it's graphics. The SMS VDP is a direct descendant of the tms9918a (it supports all of the tms9918a's modes), and does in fact add a 4bpp mode. In that mode, you have access to one of two palettes of 16 colors per tile (sprites are forced to use the second palette, no choice there). The mode is called "mode 4" in the master system world, and would be a nice complement to ECM1..3 in my opinion. 

 

But I fully understand that my opinion is just that... one of many opinions. I would prefer this way of extending the F18A, some other people might be more in favor of extensions that follow the programming model of the Yamaha 99x8 chips a bit more closely, while yet other people would like a more CGA/EGA/VGA based approach. Can't please everyone, and I for one am pretty excited to explore whatever Matthew comes up with eventually.

 

I'm note sure if you already discovered this, but /if/ you don't mind losing half of the horizontal resolution, the current F18A actually does support a full 4bpp bitmap layer that can span the entire screen.

 

Alternatively, as Tursi has pointed out, the current F18A in ECM3 mode actually does give you more than 16 colors on screen (up to 63, like the Sega Genesis), and is only limited to 15 colors per 8x8 tile. And that is without resorting to scanline tricks. I would love to see if we can take an image of yours and use the current F18A features to show it on screen, unaltered, using a combination of the techniques available to us. Any chance you can give me a sample of some 16 color art you'd like to get running on the system? I'd be happy to give it a go!

Edited by TheMole
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Absolutely! How large of an image would you like, and do you have a preferred subject?

 

I have a handful of old art floating around, but nothing terribly special. I tend to favor images around 100x100 px. (I pixel art mostly as a hobby, rather than for any specific intent, but usually use between 12 and 15 colors. )

 

Edit:

Here's a bluejay I made some time back, that uses 20 colors (including transparent color). With some thought I could probably down-sample it to 15 with acceptable results. It would not work with a general purpose palette though, it would dominate the whole thing with blues.

 

bluejay-zps178295c7.png

 

I also have a silly little thing I made for an art community when the topic of drawing hands came up... (many people have problems drawing them, but I am not really one of them.) It uses 17 colors, most of which are probably the aliasing of the text.

 

Hands-Are-People-Too-zpscdc9a039.png

 

I have this capricious habit of not holding onto things I draw, because the fun is in making not keeping them.

 

I dug some more-- this came up in the old dwarf fortress forgotten beast art contest. It uses what I consider to be "A whole lot of colors", at 49 colors. Most of them are deep shades, which could be substituted/culled. I used to draw quite a lot of those, because it was fun, and good practice. This guy was a giant, blood red mite that sucks blood. (the FBs are generated from a random selection of features, and are only described in text form, hence the contest to draw them.) Sadly, my current job does not afford me lots of time to doodle like my old one did.

MD-zps8fcade31.png

 

Another I did for that contest, was a massively-overdone scene that uses 256 colors exactly.

composited-zpsf27760bb.png

 

 

I seriously doubt I would ever get the luxury of 256 on-screen colors like that with the TI (Seriously, that's SVGA shit.), but I really can do a whole lot with very little.  Just not "8 colors" little.

 

 

Edited by wierd_w

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2 minutes ago, wierd_w said:

Absolutely! How large of an image would you like, and do you have a preferred subject?

  

I have a handful of old art floating around, but nothing terribly special. I tend to favor images around 100x100 px. (I pixel art mostly as a hobby, rather than for any specific intent, but usually use between 12 and 15 colors. )

Hmmm, no preferred subject I can think of now, although I'm still hoping I can start work on that Activision Ghostbusters port one of these months years ;). Anything within those limitations should work! Oh, and ideally of course something within the 12bpp master palette of the F18A, so I don't have to reduce a 16bpp or 24bpp image down to the 12bpp color resolution of the chip which might affect your shading.

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I just tried the two first images in my home-grown F18A tiler program, and the first one doesn't load without modifications to the patterns. Now, keep in mind that this program is not designed to optimize palettes, so with some care I'm pretty sure we should be able to get it to display as-is.

 

The second one worked on the first try and only uses four out of 8 available palettes:

407246536_ScreenShot2019-10-07at14_54_08.thumb.png.c4651c96e1f86fc6f6a2566f7c37177c.png 

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Is there a non-macos version? (I see those decorators. That is either some awful gnome skin, or macosx.) I think I could make good use of such a tool...

 

 

I have the next two days off, I think I can make you a nice ghostbusters "press fire to start" screen, but first I need to go collect some data. Since a 15 color general palette is so limited, I want every color to matter, so I am gonna go super geek cred, and pull the "normal color vision peak curves" data I have seen before on the net, and use that to produce color pick biases, so that colors favor those best discerned by human eyes. (From the colors made available in the 4096 color color-space of the F18A, of course. The idea is to pick colors as legitimately as possible, not based on their mathematical values or properties. If I can get away with optical illusions for color reuse (See also, "Is this dress yellow or blue?"), this info will help me do it.

Edited by wierd_w
(cat on keyboard)

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Meanwhile, at VCF every year I speak with people who work on modern systems and say it is the limitations of old technology, e.g. the 9918A VDP, and the challenge of breaking those limitations to do what people would think otherwise impossible as the attraction.  The VDP does not have the bandwidth to do motion video -- counterpoint: Tursi's Spaceballs demo and the subsequent Dragon's Lair*.  Then for color limitations we have there is fast switching between multi-color and bitmap modes to blend colors (the girl holding the flag in Don't Mess With Texas.)

* Not ignoring the digitized sound.

 

The argument of artificially limiting functionality because of the vintage of the technology is a deeply philosophical argument, embodied in my "non-99/4A way" statement, which is not unique to the TI community.  The F18A in its original form (not even its final form!) is shunned by some, and a debate could be had that the NES-like mode it provides may just be blasphemous as nothing more than a 9938 should ever grace the temple of silver and black.  (I mean, if you want a game with NES graphics then just play an NES, amiright?)

 

A couple of examples of defeating old limitations on other platforms: Majesty of Sprites on the Commodore 16 and Plus/4 and 8088 M.P.H. on PC hardware.

 

Using modern technology to radically increase functionality raises the issue of taking away the character of the original system.  I posit much of the charm and character of the 99/4A is lost as soon as you graft a 640x480x8 or 1024x768x16 graphics mode onto it as you might just have a 9900-based PC-a-like on your hands.  These artificial or arbitrary limitations are enforced as a means of preserving the spirit of the original design.

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the problem with that kind of thinking though, is that it embraces magical-ness, and implies "the way it was intended!!" on everything.

 

System engineers dont set out with such high ideals.   they are given a problem, a budget, and then that budget gets cut, repeatedly. What ships at the end is the result of "This is the very best we can do under the limits imposed by accounting."

 

The VDP of the Ti certainly *IS* a triumph-- it can do a whole lot of things, and hardware sprite manipulation is not chump-change. (The lack of it has soured my foray into game programming from a young age-- Again, I started out life on an IBM XT era system, that only had bitmapped graphics modes, and often hard-set colors. Despite this, people more clever than I am were able to get CGA to do some very slick shit by abusing how CRT screens mangle the colors, due to the use of a shadow mask.) 

 

I just do not hold with the expectation that it is in any way holy.  I instead look at the F18A as a thought given form-- Specifically, "If those engineers were not hamstrung by expensive silicon, what would they have made in this form-factor and package size?"

 

In this respect, I suppose I am more in favor of the direction the Amiga community took, with how they devised wholly new graphics hardware, added PPC accellerator cards, etc-- to their systems.  Adding those things does not make it stop being an amiga, or detract from its character, IMO.

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1 minute ago, wierd_w said:

In this respect, I suppose I am more in favor of the direction the Amiga community took, with how they devised wholly new graphics hardware, added PPC accellerator cards, etc-- to their systems.  Adding those things does not make it stop being an amiga, or detract from its character, IMO.

Obviously, you have never had a long conversation with an Amiga purist ;)  You know some of those nuts completely eschew RTG?!

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Oh, I know all about how rabid those people are... :P

 

My perspective is more this:

 

1) I did not own a Ti as a child, and so have no nostalgia giving me "expectations."

2) I am a pixel artist that does not want to wade through 500 different libraries just to display something. (So older systems are appealing.)

3) The lack of hardware sprite manipulation means having to do loopy-loops with graphic state of the display, and I would rather avoid having to deal with all the snarls of "Yet another graphics library" just to preserve backgrounds, and have good moving objects on screen, without things slowing down slower than the pitch drop experiment. This has soured my forays into game making, despite having a useful skill in that area. ( I have several game concepts I would love to realize, but found my desire to make them was not sufficiently motivating to deal with the byzantine bologna of the contemporary BASIC libraries for the system I cut teeth on to overcome these.)

4) The Ti has hardware based sprites. (YAY!)

5) It is also simple, with little library overhead. (YAY!)

6) It has an aftermarket VDP that is more capable, and a new model is being discussed (YAY! If they give me a mode I can make use of, I can make use of it!)

7) There are people that appreciate the platform, so work made for it will be seen by at least somebody other than me (YAY!)

 

So, the platform looks desirable to me, which is why I got one. 

 

Then I found out "Oh, 1bpp from BASIC, because yeah.."  along with "Character based drawing and pals" and "We expect you to burn up all your sprites if you want more than a single color." (which makes me sad. :()

 

Then I see RXB gives access to ECM3, and I go "YAY!"

 

Then I note that ECM3 expects you to cut up your color space in terrible ways. :(

 

I state that I can do a shitton with 16 colors, if you can manage it for me, and end up in a shitstorm. :(

 

 

 

 

Edited by wierd_w

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I'm not on this thread every day but I thought I would toss in my $0.02.

 

I'm probably about the only person on here that isn't as excited about the MK2 as I was about the F18A.  The thing that I am MOST excited about the MK2 is the size (same size as DIP40 which opens all kinds of doors to homebrew computers).

 

I read all of these requests for this and that.  Some seem crazy.  Some seem reasonable.  But I certainly fall into the camp of keeping a TI as close to a TI as possible.  I bring out my 486 when I want VGA.

 

Now, I do want an MK2.  Especially for my Coleco ADAM and one of my TI's.  My needs are pretty simple.  To me, the perfect VDP is one that has all of the original TI modes, plus a few extras with "NES like" graphics being high-end.  I actually thought the bitmap mode and 100 MHz GPU of the F18a was too much.  GPU could have been the same speed as the TI and I would have been happy.  I also like the artificial limits to keep the spirit of these machines alive.

 

The only exception is the output.  HDMI is nice but VGA is just as good (for ME).  Especially since many new monitors still support VGA.

 

In fact, if I had the FPGA skills, I would design a cheap solution that had all of the modes of the TI, 80 columns, 32 sprite scanline fix and VGA out.  And that's it.  No GPU, no bitmap layer, etc.  That would be the "lite version".

 

The "super version" would be the same as lite but add X/Y scrolling, small GPU and more RAM.

 

I would never have more than the LITE or Super versions. 

 

I think the more important thing about the F18a that most people miss is that it's become a standard.  To me, that's more important than feature X or feature Y.

 

But, that's just me. 

 

 

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I understand completely why wierd_w would like a 16 color (ECM4) mode. I would also like a better bitmap mode. I'm suggesting it because I would like to use it, and with the MK2 it will finally be possible.

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Hi, I'm newbbie with the TI-99/4A, in fact I get a unit 2 weeks ago and I already installed the FinalGROM99 and 32K memory expansion. Until now I was using the video composite output in black&white because the european models have not color composite output. Finally I built a components cable but as I read everywhere the colors are not correct on the screen. It seems that the only solution to this is the F18A MK2 but after reaading some pages of this thread here I'm not sure if I well understood:

 

It stills being under developpement?

There's any expected launching date?

Will be compatible with the TI-99/4A european models?

 

Can someone kindly confirm these points?

 

Thank you!

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Matt'll have better answers, but in case he doesn't get in for a few days:

- it's still under development

- there's no launch date yet

- it should work with the Euro machines, but be warned that it will (probably, if like the original) switch your frame rate to 60Hz. That won't be a problem for your monitors but if you are used to TI games at 50Hz, they'll suddenly seem faster. (Well, the ones that were fast enough to be frame locked, anyway. Music and sprites for sure.) ;)

 

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18 hours ago, wierd_w said:

Is there a non-macos version? (I see those decorators. That is either some awful gnome skin, or macosx.) I think I could make good use of such a tool...

 

It's really not a general purpose tool, and is basically a collection of hacks to help me get the maps for Alex Kidd converted from png to a raw tile format usable with the F18A. Having said that, it's an SDL program, so in theory it should run on any supported platform. I've never compiled it on anything besides a mac though. Let me know if you want to have the source code to play around with...

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5 hours ago, Tursi said:

Matt'll have better answers, but in case he doesn't get in for a few days:

- it's still under development

- there's no launch date yet

- it should work with the Euro machines, but be warned that it will (probably, if like the original) switch your frame rate to 60Hz. That won't be a problem for your monitors but if you are used to TI games at 50Hz, they'll suddenly seem faster. (Well, the ones that were fast enough to be frame locked, anyway. Music and sprites for sure.) ;)

 

Many thanks for your response, I was not aware about the frame rate moving to 60Hz. Unfortunatelly it seems that the only solution for me is to find a monitor or video converter that can correctly show the components output video signal 😖

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Being a long-time Commodore 64 owner, it's odd for me to see people struggling to adapt to NTSC.  It's usually me trying to adapt to PAL.  😕

 

Anyway, whatever you got to do, I would recommend it.  The TI is such an underrated platform.  And with all of these new hardware goodies recently, it's only getting better.  I WISHED I would have had the TI I have now back when I was a kid.

 

You won't be disappointed.  🙂

 

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6 hours ago, TheMole said:

 

It's really not a general purpose tool, and is basically a collection of hacks to help me get the maps for Alex Kidd converted from png to a raw tile format usable with the F18A. Having said that, it's an SDL program, so in theory it should run on any supported platform. I've never compiled it on anything besides a mac though. Let me know if you want to have the source code to play around with...

image.thumb.png.60a159a6a5814a903358b85646509a83.png

 

Magellan can also work with ECM3.

 

image.thumb.png.7fcccbe668e2ebce0c8501585c2b6820.png

 

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Here's my two cents (and I'm investing a lot more than 2 cents in coding and hardware)

 

There has been only a modest amount of software taking advantage of the F18A graphics, and a chunk of it is all Rasmus. To my knowledge, there are no F18A-only software.

 

The installed base is, at best, a few hundred F18A (matthew would know). This is going to explode with mk2 (I hope matthew can keep up.) The mk1 has limits to how much its firmware can be upgraded. It is also limited to 16k VDP RAM (+2K for GPU).

 

As a programmer, my motivations are: target the installed base, get users. I want to make an F18A only game. 

 

Digging deeper into my motivation, I was embarassed that when I wanted to show off my new Geneve 9640 with Yamaha V9938, back in 1988, all I had to demo was.. Parsec, using the 9918A G2 mode. It occurred to me that for a new Geneve2020 (9958 or F18A?), a new Parsec was required. That's how my brain works :) FYI, there have been V9938 and V9958 upgrades for the 4A way back, but not a lot of software for them. 

 

Making a F18A mk2 mandatory software would start from an installed base of zero... at the very least, it has to have a backward compatible set of graphics.

 

That said, as a V9938 programmer from way back, I would be excited to see any of the V9938 modes in F18A mk2, but that's not matthew's goal.   Mode G4 from SMS was mentioned. This uses 32K per page for 256x212 4bpp. Mode G7 offers 256x212 8bpp in 64K.

 

Squeezing ECM3 *tile* mode into the 16K of the F18A is already pushing the limit. Here's how I spent my budget:

 

2K for TL1 scrolled name table + tile attribute table
2K for TL2 scrolled name table + tile attribute table + sprite attribute table 
6K for 256x8 tile patterns in 3bpp
3K for 32x4x8 sprite patterns in 3bpp
2K for 256x32 BML in 2bpp
--
15K

 

In 16K, increasing any one of these features means trading off one of the others. I started with TL2 at 4K, which limited BML to 1K (two rows). There are scrolling problems to solve to get an unbounded map, and I needed BML to fix them.

 

This is supported by a chunk of CPU RAM (32K to use, and I'm planning on 512K flash cartridge). 3K for a name table buffer, and potentially 48K of Flash for sprite patterns, to constantly update the 3K sprite pattern table. For now, the demo fits in the 32K.


Working out what is possible within these limits, I saw the firing solution that Tursi already re-stated. Doubling up the sprites lets you take from 14 colors. There's a budget, and I can spend it on some doubled sprites (important ships and monsters) and single sprites (bullets, rockets). 

 

If F18A mk2 could expand to "ECM4" using more memory, great. As matthew said, it probably exceeds the bandwidth of the F18A's chip, so no firmware upgrade for existing F18A owners. And +1bpp taking up another 2K would entail sacrificing something else out of that 16K. That again is the budget constraint. And it's still tile-based, not bitmapped, so less than an Apple IIgs or Amiga with 32K or 64K to throw at the problem. (By the way, the solution to paging across 128K memory, in a compatible way, is demonstrated by the V9938's 128K with higher bits in another register. Not more address lines.)

 

In summary, my goal is to work with the installed base we have now. 

 

 

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Hey, wierd_w, everybody, go check out this early demo for P2 (ssh, the actual title is a secret). https://gitlab.com/FarmerPotato/parsec2/blob/master/dsk/p2.dsk

 

F18A is mandatory.  Load it into JS99er.net it runs just fine. That even works on an Android phone. :) 

 

The first ship in 16 rotations and 3bpp is by wierd_w.

 

Right now, my 12 year old is thrilled to be designing the cave maps, using a tile set I threw together, but that's just a stand-in.

 

Source code: https://gitlab.com/FarmerPotato/parsec2/ 
 

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3 hours ago, FarmerPotato said:


Hey, wierd_w, everybody, go check out this early demo for P2 (ssh, the actual title is a secret). https://gitlab.com/FarmerPotato/parsec2/blob/master/dsk/p2.dsk

 

F18A is mandatory.  Load it into JS99er.net it runs just fine. That even works on an Android phone. :) 

 

The first ship in 16 rotations and 3bpp is by wierd_w.

 

Right now, my 12 year old is thrilled to be designing the cave maps, using a tile set I threw together, but that's just a stand-in.

 

Source code: https://gitlab.com/FarmerPotato/parsec2/ 
 

I did!

 

Looking good so far!  Looks like we need something to shoot. (both ammo and target.) :) 

 

Painful to control with a keyboard though. No reverse thrust option.

 

 

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