Making new games with Intellivision constraints

[8bitwidgets.com]

Hi there, 

I'm not a traditional developer.  I use a tool called Construct3.  It's an HTML5 based 2D game engine.  Knowing myself, I'll never have the time or motivation to become capable of making actual intellivision games on the system (which I have and it was my first console way back when..) but I can make games like it..   i did this prototype extracting animation frames from a image online..   https://part12studios.com/games/Bitly/Bitly01/

 

So it got me thinking..  maybe if I had some clear idea of the limits of what an intellivision game could do..  resolution..  color pallet depth / shades..  sprites on screen..  voices..  audio range..  memory limitations..  just general understanding of how far you could push an actual intellivision perhaps I could create games that feel like they could be on the intellivision and adhere to as many constraints as possible..  

 

Thanks!

Caleb

Edited February 10, 2021 by Caleb Garner

[+Steve Jones]

It’s amazing what you can find in wikipedia

[wolfy62]

54 minutes ago, Caleb Garner said:

Hi there, 

I'm not a traditional developer.  I use a tool called Construct3.  It's an HTML5 based 2D game engine.  Knowing myself, I'll never have the time or motivation to become capable of making actual intellivision games on the system (which I have and it was my first console way back when..) but I can make games like it..   i did this prototype extracting animation frames from a image online..   https://part12studios.com/games/Bitly/Bitly01/

 

So it got me thinking..  maybe if I had some clear idea of the limits of what an intellivision game could do..  resolution..  color pallet depth / shades..  sprites on screen..  voices..  audio range..  memory limitations..  just general understanding of how far you could push an actual intellivision perhaps I could create games that feel like they could be on the intellivision and adhere to as many constraints as possible..  

 

Thanks!

Caleb

Welcome Caleb!

If a couple of the very knowledgeable and helpful developers that stop by every now and then see this post they may reply.

As I am basically just a player and collector,I can only steer you in the generally right direction. 

There is an Intellivision programming section here in Atariage as well and if you look up Nanochess and his Intybasic programming book that should be extremely helpful as that is what most folks are programming the latest homebrews with.

Just wanted to reply and let you know there are a lot of great and helpful people here.

And if any of my info is wrong they can feel free to correct me for sure!??

[+cmadruga]

So the idea is to make PC games that look and feel like Intellivision ones?

What types of games would you do? Sequels? Different takes on classics?

 

Depending on how precisely you want to simulate the constraints, you might as well just make a real Intellivision game. IntyBASIC is very beginner friendly in my opinion.

[carlsson]

1 hour ago, Caleb Garner said:

resolution..  color pallet depth / shades..  sprites on screen..  voices..  audio range..  memory limitations.. 

The resolution is 159x96 pixels ordered as 20x12 cards in the so-called BACKTAB which all are 8x8 pixels (rightmost pixel column not visible IIRC). That means it is not fully bitmapped, but based on a character set that consists of up to 256 fixed GROM symbols (including alphanumerical characters, punctuation and some executable code that looks like random garbage but can be used for explosions) and 64 dynamic GRAM symbols. You can reload the GRAM on vertical blank, limited number of cards you can redefine per frame. The palette is fixed, 16 colours which you can find elsewhere exactly what those are supposed to look like. There is one colour that sometimes is considered forest green, sometimes brown depending on the surrounding graphics.

 

Basically there are three major graphics modes:

 

Color Stack which lets you define four background colours to cycle through, and use all 16 foreground colours (primary 8 for GROM, all 16 for GRAM). In this mode you can use all 256 GROM symbols plus all 64 GRAM symbols.

 

Foreground/Background which lets you freely choose background among all 16 colours for each card, but you may only use the 8 primary foreground colours, plus that GROM is limited to the first 64 symbols (numbers, punctuation and upper case letters) on top of the 64 GRAM symbols.

 

Colored Squares mode which is a variant of Color Stack that cuts the resolution down to 40x24 blocky pixels, and you can use all four colours defined freely.

 

You can have a maximum of 8 sprites on screen. These have a resolution of 8x8 pixels, or alternatively 8x16 pixels. Those are defined as part of GRAM so the same area is used for foreground objects and sprites. Sprites can expanded to twice the width and between 0.5x and 4x vertically, making them very tall. Each sprite only has one colour, if you need more you have to use multiple sprites on top of eachother.

 

Sound: It has an AY-3-8914 which has three square wave voices, of which you can make some channels generate white noise instead. The frequency resolution is 12 bits (4096 steps). I can't recall the exact frequency range, but generally the resolution between each audible note is more important than how many bats and dogs you can scare.

 

Memory: The base system has 240 bytes of 8-bit Scratch RAM, 352 words of 16-bit System RAM  (of which BACKTAB uses 240 words), 512 bytes of GRAM (64 cards * 8 bytes). Modern games can map out ROM up to 42 kilodecles (that is 84 kilobytes) without getting into bank switching. Not sure if you have use of this information if you're simply going to mimic the look and feel of the Intellivision.

 

Generally I agree with the above posters, you might find that using IntyBASIC isn't that much harder than make accurate imitations in HTML5, in particular if you try hard to not bend the rules.

[8bitwidgets.com]

@cmadruga yea mobile or PC games.  just capturing the feel / vibe of Intellivision games that i grew up with..   i have this game idea.. a kind of wreck it ralph like story where you're basically a self aware entity and are trying to work your way out of an game system (intellivision?) to the outlet, but have to survive the various games someone is putting in the system without crashing the system forcing the user to pull the plug..  survive the numerous mini-games and win your freedom in the electric grid..  

 

I'll check out IntyBASIC, totally never heard of that before.  I have some programming experience but yea i was imagining this stuff would be at some assembly level magic.. that is beyond me..   but i know even basic still takes some time to learn / use so unless IntyBASIC is somehow even easier than basic.. I could see it being a task to really master..   I have a sinclair 1000 and a book on basic for it i was considering diving into..  but even that got kinda deep making some decent games..   none the less my interest is peaked for sure!  

 

@wolfy62 thanks for the welcome!  i'm stoked as I wait for my intellivoice to come in..  i bought an intellivision flashback, but when i heard the audio for night stalker just wasn't the same.. i knew i had to get an original system..   and yea this is awesome.  IntyBASIC sounds really interesting.  I need to follow up with the guy who had a MIDI cartridge for intellivision..   as I've done a SIDFX (two sid chips in one C64) mod and the idea of being able to make midi music with an original intellivision is just too cool to not try out.  i think the intellivision had some amazing sounds and to be able to play with the same audio chip would be so cool.  

 

@carlsson  thanks so much for this awesome breakdown.  this is a big help.  I'm going to really study this tomorrow. and see what i can make with it.  i know that the HTML5 game / framework is obviously nothing close to the efficiency of how games on the original hardware were made / written, but it's still incredibly helpful to have that understanding of how much you could do with the hardware.  

 

I'll have to see if i can find the color pallet and maybe possibly sample each color to match the pallet to get the exact same red, blue, etc..  being only 16 total colors that shouldn't be to hard to find.  

 

yea construct is very easy to work with and has no coding.  that's why even simple languages like basic are still more involved than the event based visual style of Construct.  Still I do want to investigate it further.  

 

Is the only way you could test your games on a real intellivision is to buy a LTO cartridge or are there other, perhaps simpler flash carts out there that could hold, say.. one game?  

I'm working on a BBS Style website for my game using Construct.  it's the website for a video game (not meant to be Intellivision style) but the game is set in 1998.. two years after the earth is ravaged by a shattered comet (looking forward to seeing how greenland is, as this movie popped up well after we had decided this.. heh) https://roaddefender.com/  the chat room is my current door..    captain marvel did the 90s' website so well i wanted to try something a little more different and appropriate.  so the tool lets me do a lot of fun stuff that while not as authentic as coding from scratch, gets me in the ball park with the precious time I have.  

 

@Steve Jones yes, but I was curious about a human interpretation.. some working examples they might be able to site.  carlsson's breakdown was amazing.  I was not sure if there might be more subjective examples that folks might be able to share beyond the straight stats of this chip or that bus speed. 

 

So cool. So much respect for devs who both pioneered the games of the intellvision's commercial era, as it was a huge part of my childhood..  remember waking my mom at like 1am when I managed to get space armada to the level where the border is black..  lol.. must have been 9..  what was i doing up that late playing games?    that said, the fact that people are making new games with the original hardware is also admirable.  

 

Sincerely,

Cal

 

Edited February 11, 2021 by Caleb Garner

[+Gemintronic]

You've probably already gone through the YouTube videos that showcase Intellivision titles.  Also, played through the back catalogue via emulation.

 

So, really the only thing that got me farther is reading this book and typing in the programs.

https://www.lulu.com/en/en/shop/oscar-toledo-gutierrez/programming-games-for-intellivision/paperback/product-1p7mvg87.html?page=1&pageSize=4

[+fdr4prez]

1 hour ago, Gemintronic said:

You've probably already gone through the YouTube videos that showcase Intellivision titles.  Also, played through the back catalogue via emulation.

 

So, really the only thing that got me farther is reading this book and typing in the programs.

https://www.lulu.com/en/en/shop/oscar-toledo-gutierrez/programming-games-for-intellivision/paperback/product-1p7mvg87.html?page=1&pageSize=4

That guy has been known to frequent these parts 

[+Gemintronic]

2 hours ago, fdr4prez said:

That guy has been known to frequent these parts 

 

Figured he'd be leary if I told him I helped go through the examples before publishing for Óscar.  But, the jig is up!

 

You'll find it's easy to get into the Intellivision.  AtariAge makes paying tribute to our favorite systems eminently possible with its community.

[8bitwidgets.com]

@Gemintronic I did see the showcase titles.. very very cool to see!  Never enough examples of real games made both past and present to further identify what is impossible and and what is INpossible =D

 

what or who is Oscar?  

 

Yea I can see that now.  I've not really been to this site much before.  I'd visited here and there awhile back but now.. I have more reason.  2020 turned into a kind of vintage console collecting year of systems I'd had or wanted to have for my kids to experience fully, but this only became possible / practical for me with the advent of the MultiCart.  I'd not realized till last year that there we so many affordable carts that could effectively fill an entire library or significant chunk of titles in a single cart.  That was a game changer for me.  Otherwise the prospect of dozens if not hundreds of collective physical old carts seemed impractical..    except the intellivision..  getting various classic carts was INpractical..  XD   ok i'll see myself out, no really.. please don't get up.  

 

@fdr4prez thanks for that link.  I am going to bookmark that book.  How close to BASIC is it?  or is it like the way JavaScript is only similar to Java in name?  

 

 

[carlsson]

6 minutes ago, Caleb Garner said:

what or who is Oscar?

The developer of IntyBASIC and a prolific coder, generally working at least 10 times faster than many of us others. I can as well tag @nanochess to let him know he's mentioned.

 

The language mostly follows classic 8-bit BASIC syntax except it doesn't use line numbers, has support for more advanced structures and tailored towards Intellivision capacities. Due to memory limitations, you need to be a little more careful about wasting variables, string handling is a bit more of a challenge, same about floating point but for most games you would be working with integer math anyway.

 

I'm sure that Construct in developing HTML5 apps could be used to test out concepts and graphics, as long as it is able to set up actual limitations so your results could be transferred to real hardware later. It kind of reminds me about the Windows game Bruce Lee 2 which was created with a look and feel of C64 (and Amstrad CPC). A few people considered implementing the game in real C64 code and a friend of mine succeeded. I know he pulled his hair trying as closely as possible making the game look like the Windows game, but in a few situations the original programmer had taken liberties that a real C64 barely or not at all would be able to reproduce, so my friend had to find ways around it. To a casual observer the differences may be barely noticeable but if you check every pixel on every frame, there are differences.

 

It is also a matter of which target audience you have. Do people play browser based games mimicking old systems, and for how long before they move on to the next? If you put your heart and soul into making actual homebrews, you have a well defined community (here) who would be interested. Sure, many would still move on to the next game but the pool of new games supposedly is smaller than when it comes to generally browser based games, or for that matter apps running in a phone.

[8bitwidgets.com]

ah ok awesome.  yea that's so cool.   

 

Very interesting about the basic stuff.  Yea that is definitely something to think about.  I've had an intention of learning how to write in basic so yea between this book and the community I definitely could see trying something out.   I definitely see it would be that much more rewarding to actually play a game ON an intellivision.  That I have no doubt.  

 

what were games originally written in?  Would be really cool to see an Intellivision SDK.  Whatever form that took at the time.  What systems were used to compile / test / etc..  

 

I always wondered (as a musician) what tools did music composers use to make music for systems like Intellivision and NES..  seems surprisingly sparse info out there from what I've googled..  i mean there are ways to make chip tunes today but these tools are modern..  not THE software used in the 70s and 80s.. 

[carlsson]

You have a historic overview in this thread: https://atariage.com/forums/topic/259003-intellivision-development-back-in-the-day/

 

[+DZ-Jay]

2 hours ago, carlsson said:

You have a historic overview in this thread: https://atariage.com/forums/topic/259003-intellivision-development-back-in-the-day/

 

Warning:  It's not for the faint of heart.  Development back then was done in pure Assembly Language, with what we have recently discovered were very advanced tools for the day, but utterly primitive by today's standards.

 

Note that, up until IntyBASIC came along a few years back, homebrew development on the Intellivision was just slightly less primitive than what was done back in the day.

 

     -dZ.

[8bitwidgets.com]

@DZ-Jay  Yea I'm afraid making pure intellivision, O2, colecovision or 2600 games would be beyond my time limits, but who knows some day maybe.  In the meantime I could design a game with modern tools that works within at least some of the visual / audio then if i wanted to port them over at least the constraints would likely carry over..  though i realize it would still need to easy to have more going on beyond the graphics (like say physics) if I'm not careful could still be impossible to get to run on original hardware.

 

I'm in the process now if getting a multicart so I can at least have the ability to load a game on the original hardware.  I know there is emulation, but it's more fun to think i could run it on the real thing.  =D

[Zendocon]

If you ever choose to dive into real Intellivision game development, the first thing you want to do is buy the books @nanochess released.  They're quite painless to read, and each book has a few examples of full games, with all the code modules, and an explanation of what is happening at each step.

 

My contribution to the scene was to create a full development environment that runs on Android devices.  In its current form, it resembles a full Linux desktop with all the software you need to play and develop Intellivision games, plus a graphical front-end I built for playing and development.  I also left instructions on how to build the environment, and give the reader just enough working knowledge of Linux to put it to use, for people who haven't used Linux before.

 

The reason I made an environment for Android phones/tablets was so that I could write a little bit of code in the cracks of time I had.  With a schedule that didn't even leave me any time off during the weekend, I was able to develop three games within this environment which went on to be released.  All you need is a physical keyboard with your Android device.

 

As somebody pointed out as well, there's also a programming forum where we all help each other.

[8bitwidgets.com]

ok @Zendocon damn you make it hard to not take up that opportunity..   I do find the idea of making games on the hardware is really appealing!   I would love to try my hand at some real intellivision games.

 

When I finally get a LTO multicart, maybe in the next couple of months, I'll check out those books and at least get some kind of "hello world".

 

I'm just frustrated that there are not more multicart options for the intellivision..    I've tried to reach out to UnoCart makers and AtariMax to see if there is some options in the works out there..    I've been loving their  2600 and Colecovision products..    

 

Also is there some time period where a post can no longer be edited?  I cleaned up my website and the url broke for my original example up top.. no biggie, but just for posterity..  

https://part12studios.com/misc/games/Bitly/Bitly01/

 

 

Edited May 10, 2021 by Caleb Garner

[Zendocon]

39 minutes ago, Caleb Garner said:

ok @Zendocon damn you make it hard to not take up that opportunity..   I do find the idea of making games on the hardware is really appealing!   I would love to try my hand at some real intellivision games.

 

When I finally get a LTO multicart, maybe in the next couple of months, I'll check out those books and at least get some kind of "hello world".

 

I'm just frustrated that there are not more multicart options for the intellivision..    I've tried to reach out to UnoCart makers and AtariMax to see if there is some options in the works out there..    I've been loving their  2600 and Colecovision products..    

 

Also is there some time period where a post can no longer be edited?  I cleaned up my website and the url broke for my original example up top.. no biggie, but just for posterity..  

https://part12studios.com/misc/games/Bitly/Bitly01/

We're all happy to help.  The first book gets you going right away and creating "Hello World".

 

If you're having trouble getting ahold of an LTO Flash right now, see if you can get a Cuttle Cart 3.  The original solution was an IntelliCart, which was an Intellivision cartridge with a serial cable for older computers, that allowed you to play a game on real hardware from a ROM image.

 

There is definitely a time-out period where posts can no longer be edited.  I want to say 15 minutes, but that's a wild guess.

[8bitwidgets.com]

ok awesome, it's on my list now

 

yea no luck it seems with any of the alternatives..  seems like all the other options are discontinued..   I have plenty of older computers with serial so that's no biggie..  but yea still gotta find something that works..  LTO should come around eventually.  Last batch came and went and I thought I was on the list but apparently wasn't.  None the less, it will happen soon..  can't wait because i really dislike having to swap carts over and over..  not just the effort, but more importantly the wear and tear over time..  

 

As for the timeout it looks like it's 1 hour.. which is understandable. 

[Zendocon]

Although I personally don't like web-based solutions for development, I'm hoping Intellivision is added to 8-Bit Workshop for people who would benefit from that.

 

Keep an eye out for more LTO Flash carts.  There's a demand for more, so it's a matter of time before another batch is made.

[8bitwidgets.com]

yea it will come up..   yea i figure at some point i'll want to figure out how to use the intellivision emulator for development / testing..   but i really do want to, on day one run my first project on real hardware.  this isn't a requirement but it's a motivating factor for me.  

 

Yea the 8-bit workshop looks pretty cool and yea if something like that let's you test your code easier, i'm all for that.  it's really just nice if there is a good workflow.  Would be nice to be able to practice projects / concepts when I'm at work.  

 

I enjoy using Construct 3 for my game development needs, but admittedly it's really best if it's all browser based, but then becomes tougher to monetize...  moving to mobile becomes a pain..  between things like ads/IAP and other 3rd party features.. sometimes things can become a bit of a drag.. like.. making the game is fun.. but then getting it to a market is a pain..  

[+fdr4prez]

2 hours ago, Caleb Garner said:

As for the timeout it looks like it's 1 hour.. which is understandable. 

Yes, it is one hour.  If you want to help support the site, then you can become a subscriber and then you have a 30-day edit window.

 

In the programming subforum, and a few other subforums, if you create a thread, then you can always edit that first post.

[8bitwidgets.com]

nice @fdr4prez