[redconfetti]

I've thought to myself that if I want a cool project that would motivate me to re-learn C just for the sake of making an NES game (ala 8-bit workshop - https://8bitworkshop.com/), I would really like to learn how to apply the pseudo-3d or 2.5d methods that were used by Microprose in F-19 Stealth fighter.

I don't know the first thing about 3D programming. I tried to follow a book on writing a ray-tracer from scratch just to see if I could pick up the principles and do it myself, but I got frustrated by the ambiguity of the approach. Like I was trying to use Ruby with Rspec, but I'm not even sure if I'd run into a performance issue or not be implementing the interfaces correctly.

I just want to know what method was used. Maybe 3D projection?

https://en.wikipedia.org/wiki/3D_projection

Microprose had 3D flight simulators going back to 1984 on Atari 400/800, Commodore 64, and IBM PC. That's really impressive.

https://en.wikipedia.org/wiki/Hellcat_Ace

Kind of like how Myst was able to deliver ultra-high resolution 3D images in a video game in ways that had never been done before, even though it was really just a point-and-click slideshow with embedded videos and scripted interactions (Hypercard)... Hellcat Ace provided an experience far ahead of its time.

[phire]

> I would really like to learn how to apply the pseudo-3d or 2.5d methods that were used by Microprose in F-19 Stealth fighter.

F-15 is not pseudo-3d at all.

Flight simulators were early innovators in proper polygon based graphics. Partly because there were so few polygons they could get away with the painters algorithm. Partly because the instrument panel could cover a large chunk of the screen. But mostly because players of flight sims were willing to put up with very low frame rates, even 1 frame-per-second would be considered playable for certain types of flights.

Anyway, the tricks used for the 8 bit computers and consoles were nothing more than distilling down the graphical complexity until all they really had to draw was a tilting horizon line and then use a few sprites for everything else.

The one notable pseudo-3d technique I'll point out is the voxel based terrain used by "Comanche: Maximum Overkill". That's well documented.

[ahefner]

On the NES (or other 6502 machines), use assembly. That CPU just isn't a good target for C - pointers are awkward, you can't really do stack frames, and the addressing modes don't even support 'structs' very well. Fun to program assembly on, though. For your purpose the NES makes it double hard because it hardly has any ram (2 KB, and typically an additional 8 KB inside each cartridge except in the oldest games), and a character-mode graphics architecture rather than a framebuffer. If you do really want to do an 8-bit flight sim, the Atari 400/800 machines are an okay target. The Atari ST would be a better target.

Speaking of those machines, I'd love to see someone deeply reverse engineer the pseudo-voxel/fractal landscape engine that Lucasfilm Games invented for Rescue on Fractalus, Koronis Rift, etc. It still seems completely magical that they could pull that off on a machine with those specs.

Starting from zero, you might start at a high level and work your way down. Do a simple polygon flight engine using OpenGL and your favorite high level language of choice. Then write your own polygon rasterizer that you can overlay versus the OpenGL rendering as a reference. Then maybe rework it in pseudo 8-bit code (C constrained to only unsigned char variables, or similar), which should translate directly to assembly language on the target of choice. On a real 8-bit machine, unless you want low single digit frame rates, you probably have to pull a lot of dirty tricks. Maybe a 16-bit platform would be a better choice. This is speculative - I learned 3D (to a novice degree..) on a 486 PC under 16-bit DOS using C and assembly for inner loops (bitblts, texture mapping).

There's something about the aesthetic of late 80s PC flight sims (F-19 Stealth Fighter, LHX Attack Chopper, etc.) and their flat shaded polygon graphics that feels in vogue right now. Check out Thunder Helix on Steam.

Anyway there's definitely a magical feeling writing graphics code when you get your first feeling of realistic movement and rotation in 3D space working. Hopefully the ubiquity of ultra-realistic doesn't diminish that sensation too much.

[hooper]

If you're trying to do it all in software, you can get pretty far with a function to draw a solid colored triangle, a function to rotate 3d points using sin and cos, and some loops. Then the other pieces like lighting and texture mapping can be added pretty incrementally (depending on how obsessed you are with optimization).

There are lots of interesting pages about this. Here's a contemporary one that comes to mind: https://www.modeemi.fi/drdoom/3dica/3dica.htm

An easy way to get your pixel color array on screen is SDL2: https://www.libsdl.org/

[LowLevelMahn]

wow 3dica is a cool tutorial - thanks for the link

[pjc50]

You may like my https://github.com/pjc50/ancient-3d-for-turboc : a slightly more modern target than the NES, it targets Borland Turbo C for MS-DOS and renders to the standard game 320x200 paletted "mode 13" display.

Standard techniques of the time; project the 3D to 2D, cull backwards facing polygons, "painter's algorithm" (draw deepest first, in this case by object rather than by individual polygon).

> I tried to follow a book on writing a ray-tracer from scratch

The hardware of the time would ray-trace at multiple hours per frame. See https://github.com/POV-Ray/povray

[ggambetta]

May I pimp my own book about 3D rendering, covering both rasterization (including 3D projection) and ray tracing? There's a complete, free version at my website, https://gabrielgambetta.com/cgfs

[drivers99]

I was just thinking of this book as a recommendation to the parent post, and here the author himself posts it. For what it's worth, I can totally recommend it. I had written rasterizers in the past but not ray tracers until I went through this one weekend.

[mysterydip]

I found this book by Chris Lampton to be very helpful for my own 3D DOS pursuits: https://archive.org/details/build-your-own-flight-sim-in-c-d...

There's also various article series in the flipcode archives: https://flipcode.com/archives/articles.shtml

[myth_drannon]

Also first edition of this book from 1993: https://archive.org/details/flightsoffantasy00lamp

You can also find the source code on archive.org if you don't feel like typing everything.

[qingcharles]

I came across this yesterday which might be exactly what you're looking for (I even see an F-117A as the demo):

https://pikuma.com/courses/learn-3d-computer-graphics-progra...

As a pro game dev in my past life, I promise you can get a 3D engine up and running from scratch in relatively few lines of code. Especially something like a wireframe cube that you can rotate.

[LowLevelMahn]

thats why i love hackernews - always information that is briliant but never stumbled over it

[atan2]

Another vote here for pikuma.com. Their 3D graphics course is a must!

[wkat4242]

> Microprose had 3D flight simulators going back to 1984 on Atari 400/800, Commodore 64, and IBM PC. That's really impressive.

They weren't the only one though. Sublogic also had Flight Simulator II for those platforms. Which wasn't really combat focused (except for the sopwith camel minigame with the checkerboard and the cardboard mountains - lol). But it was also really impressive on such constrained platforms. Ok, it did about 1 frame per second and only rendered in wireframe on the Atari, but you could tune VOR and ADF radios, set weather etc. It was really impressive for an 8bit machine with 64kbyte.

Sublogic later licensed their product to Microsoft to port it to PC which became Microsoft Flight Simulator. And the rest is history :)

It was a bit weird because on the much more capable Amiga there was a flightsim game that wasn't even able to draw a tilted horizon if the gradient function was turned on. I forget which game it was, I think it might have been F-29 retaliator.

[cardinalfang]

The gradient might have been created using copper palette switching, which would cost no CPU time but only work with horizontal lines.