Quake's Lighting Model: Surface Caching (1996)

The technical knowledge in it is both out of date, and more relevant than ever.

The particular details are long since irrelevant - even in 1996 optimizing for the 8086 was irrelevant. But the thought process, approach and lessons learnt from optimizing the 8086 are still relevant today.

In fact, they're probably more easily demonstrated through and example using the 8086 than in modern environments. I still use Abrash's S3 FIFO buffer story when I'm mentoring people.

So yes, but no.

I always like to think about the fact that they went to the moon in the 1960s. We're all a bunch of babies compared to what they pulled off then.

"The on-board Apollo Guidance Computer (AGC) was about 1 cubic foot with 2K of 16-bit RAM and 36K of hard-wired core-rope memory with copper wires threaded or not threaded through tiny magnetic cores. The 16-bit words were generally 14 bits of data (or two op-codes), 1 sign bit, and 1 parity bit. The cycle time was 11.7 micro-seconds. Programming was done in assembly language and in an interpretive language, in reverse Polish."

[1] http://stackoverflow.com/questions/739561/what-programming-l...

More likely most programmers hear about the previous generation...

I remember reading Abrash's articles in Dr. Dobb's back in 1995 and 1996. They were written as Quake was being finished, and it was brilliant to follow the progress month for month.

I was in high-school, but based on the articles, I was able to build my own Quake-like rendering engine at about the same time as quake was released. I knew x86 assembler and had picked up various tricks for texture-mapping beforehand. However, I implemented a BSP-builder and a sorted edge rasterizer inspired by ID. It got pretty good. I remember struggling with perspective correct texture mapping a lot (couldn't find a reference to it. Had no internet). I cracked it solely based on a sentence in one of Abrash's articles about the "distance division". Suddenly his paragraphs about using the FPU in parallel with the CPU for texture mapping fell into place. I even developed various tools for lighting, level editing, scripting. I always wanted to do a game with it, but never managed to actually build it. Within a few years, software rendering was obsolete anyway, and the Quake engine far far behind -- I think my primary interest was in the algorithms not building the game.

I've implemented a lot of algorithms since then, and every time I work on a new difficult problem, I always think back at these articles and the challenges described.

To me, Abrash's articles were an inspiration for at least the following reasons:

1) They show that even really hard problems can be solved by tenacious individuals or small teams.

2) He presents and compares various solution approaches (with pros and cons) -- Don't settle with the first idea.

3) He and Carmack compromised and "cheated" (e.g. BSP and surface caching) for performance reasons -- Something I've ended doing myself many times. If the problem is too difficult, try to simplify it.

4) That smart people struggle solving problems too. Don't give up! Eventually you find a solution -- Carmack hadn't slept much the weekend he implemented the Potential Visibility Set, which was the big breakthrough when developing Quake.

5) Overall friendly and accessible explanations of clever ideas.

Sadly, the Quake engine is irrelevant today, and I wish someone would write a similar serious of articles about their development efforts and battles.

Does anyone know of anything similar from the past 10 years?

"Oh gee, people were so much more talented when they had to build a chair by hand rather than run a whole factory of chair building machines. If only those modern programmers working on LCH/ATLAS had the chops to compute some moon landing trajectories."

Read the book and find out! The Volvo story is also worth reading.

Correction: Video Seven story. http://www.jagregory.com/abrash-black-book/#chapter-64-quake...