[XalvinX]

In about 1980 or so i got a TI 99/4A (I was about 12) and figured out how to do high-res graphics within the limitations of what was essentially a text-only machine. By redefining the 8x8 character blocks you could manipulate individual pixels. The main limitation was that when you redefined one character, every one of that number on the screen would change, and I think there were 256 available...still though, i managed to create programs that could graph a line and draw circles, and something that was similar to Missile Command. it was also interesting in that if, for example, you filled the whole screen with a single character and then redefined it in a loop or something, the whole screen would instantly update creating mesmerizing effects. You had to be creative in those days.

[mmjaa]

My favourite 8-bit machine, the Oric-1/Atmos range of systems, had a secret video mode embedded in its bowels that we didn't know much about until this century. It turns out there is a way to do color rendering on the Oric that precludes the attribute clash that inflicted so many systems of the era .. and we didn't find out about it until one of our most elite hackers dug deep.

Since then, there's been a re-birth of new titles written for the Oric to exploit this graphics mode .. and it has resulted in titles that, had they occurred in the 80's, would have propelled the Oric far further into the scene - perhaps. (Perhaps, it was already too late for the Oric by the time it arrived...)

I find it fascinating that these machines still hold so many treasures yet to discover. And, it sure is fun to be writing software for an 8-bit machine, with only perhaps a few hundred users out there who would give a damn ..

[andrewstuart]

any references to this display mode? I can't find anything on it on the net.

[mmjaa]

Here's an intro to Oric display in general:

http://www.defence-force.org/computing/oric/coding/part_7/in...

Here's more details on the attributes mode that, when properly grok'ed, gives us color options never before seen on the Oric:

http://thespider.oric.org/oric_hires_colour.html

Twilighte (RIP) exploited this extensively for his games - check out http://oric.org/ for his titles (they're in the top-10) ..

See also this thread:

http://forum.defence-force.org/viewtopic.php?f=14&t=875

[foobarge]

Thank you - this is quite a find. I remember banging my head against the limitations of the HIRES mode and eventually doing everything in text mode with redefined characters - I was working on a windowing system at the time.

Best thing in for summer was two weeks with my grand father, my Atmos and my monitor - and certainly not my mom telling me to get out in the sun (and my grand father couldn't care less.)

[mmjaa]

Great to encounter another Atmos fan on HN .. have you been following the OricExos project? Its a system consisting of 4 Oric's, tied together, sharing duties for graphics and sound .. pretty amazing hack, if I do say so myself:

http://forum.defence-force.org/viewtopic.php?f=21&t=1880

Check out some of the demo's at the end of the thread .. it was recently booted up and demonstrated adding new color resolutions to the system. Truly mind-boggling!

[tssva]

What you described is graphics mode 1 or standard graphics. The TI 99/4a also had a mode 2 or bitmap mode. In this mode the screen was divided into thirds each being assigned their own character pattern and color table. This allowed you to change each pixel on the screen individually.

There was still a color restriction. Each row of a character could only contain 2 colors, so every horizontal grouping of 8 pixels could only be one of two colors assigned to that row in the character. This is still an improvement over standard mode which required all pixels of an 8x8 pixel grid defined by a character to be one of two colors assigned to that character.

[ams6110]

IIRC you needed the MiniMemory cartridge and the assembler program it came with (on cassette tape) to access this mode as a programmer.

[blakespot]

I typed in many a BASIC program from '99er magazine, Family Computing, Compute!, and the like that used the mode you speak of, redefining characters to be shapes of the needed sort. This was used in the program I typed in for this blog post last year: http://www.bytecellar.com/2017/10/03/a-program-from-a-35-yea...