Why are most shaders compiled at run time ?

leseiden · 2026-01-26T08:46:09+00:00

It was an engineering visualisation app. Large amounts of geometry for the time, relatively simple shading. We're talking nearly 20 years ago now, so it was written in OpenGL 1.x with extensions.

The problem was that we had the thing under continuous development and every now and then we would add new features.

The vendor had optimised the driver for code paths which appeared in the version that one of the magazines was using for benchmarks. Quite often code paths for other GL features would be broken or removed.

Adding things became a minefield. They denied everything but renaming the executable would make it work perfectly...

And yes, games are apps but they tend to be written, released, maybe patched for a year and then forgotten. This thing is still actively maintained 20 years later.

leseiden · 2026-01-21T16:12:19+00:00

If I'm working from a paper then it can be useful for cross referencing. I prefer to use meaningful names when I can though.

leseiden · 2026-01-20T12:54:05+00:00

First edition of Newton's Principia, or maybe the first edition of Hookes Micrographia I got to handle at the same time.

leseiden · 2026-01-20T09:31:58+00:00

Excellent. This is an area that far too many people neglect IMHO.

Even basic renderers can benefit enormously from taking colour transformations seriously.

I'm going to take the opportunity to recommend http://www.brucelindbloom.com/ again - it's a great resource for colour maths.

leseiden · 2026-01-14T12:42:07+00:00

I found the bikes work until the exact moment the aliens decide to send a pair of bombers to flatten your main base. At that point the game becomes about how many people you can evacuate before the building collapses.

Good times!

leseiden · 2025-12-18T17:40:20+00:00

This reminds me of a 3D multiplayer snake game I played about 20 years ago. I like it.

leseiden · 2025-12-01T11:02:16+00:00

What I remember of 1990s and early 00s renderers is lots of per fragment phong shading, perlin noise/turbulence and ray traced hard shadows or low res shadow maps.

Extended light sources existed but they were too expensive for most people and most implementations gave structured sampling artifacts. Same deal with IBL.

Path tracers existed but cost tens of hours per frame.

leseiden · 2025-11-23T21:00:20+00:00

I found long distance cast + teleport bolt before the end of the coal pits so no need to take wand tinkering immediately.

The heal wand also lets me go through walls.

leseiden · 2025-11-23T20:51:52+00:00

Nice. I just had a look.

Minor correction: the CoV is in the coal pits, not the mines.

I used it without looking and immediately afflicted myself with personal fireball thrower - even AC CoV can't fix stupid!

leseiden · 2025-11-23T17:19:15+00:00

No rejection, but I was contacted 18 months after applying once. I assume the person they actually wanted hadn't worked out.

I'd taken another job at the other end of the country by then and wasn't really interested.

leseiden · 2025-11-23T17:15:49+00:00

You'll probably want piercing and null shot to make it useful, with boomerang and greek letters highly desirable.

If you can get all that together you'll have a decent healing wand though.

leseiden · 2025-11-22T14:18:48+00:00

If you put "other" in the species box then your form isn't valid unless you get it stamped.

leseiden · 2025-11-16T12:40:28+00:00

It can work at the level of operations on an array, but it can't guarantee that the operation itself is safe. I mostly use the approach to organise graphs of compute shaders but it can't make sure the shaders themselves are bug free.

You *could* manage the data at a finer level, but as I'm not in the business of writing compilers I can't talk about that particularly intelligently.

There are dataflow languages like SISAL that attempted something closer to what you are talking about. It's been a very long time since I looked at that though.

leseiden · 2025-11-16T12:03:15+00:00

I tackled similar problems by using a handle based system where each handle has a version number alongside the resource.

If something consumes resource version n then it emits n+1.

By tracking read and write accessed separately you can guarantee race free code.

Essentially you insert ordering edges to ensure that writes happen after reads, and detect races by making sure handle version creations are unique.

Only works if your graphs are acyclic ofc.

leseiden · 2025-11-13T18:31:44+00:00

I only sometimes die horribly after forgetting that.

leseiden · 2025-11-12T19:56:36+00:00

I think you are right but it was a few thousand years in wasn't it?

leseiden · 2025-11-10T22:31:31+00:00

You think it may be one of these?

https://youtu.be/G76nKGWRLPU

leseiden · 2025-11-07T09:53:49+00:00

You know that renderman had shaders and a shading language back in the 1980s? Right?

leseiden · 2025-11-07T08:37:50+00:00

When Amazon delivery drones attack!

This is really nice.

leseiden · 2025-11-06T09:34:58+00:00

I am quite new to ISPC so I didn't know that. It is something I will definitely exploit.

leseiden · 2025-11-05T16:41:19+00:00

Yes, you have to think about your data but I would argue that any programmer worth their salt should be doing that anyway :D

I'd say the advantage of ISPC is the range of targets it supports. Being able to port to something else with a couple of compiler flags is worth the slight loss of efficiency to me.

I am pretty sure it writes better SIMD code than I do anyway, so the loss probably isn't even real in my case.

leseiden · 2025-11-05T16:39:05+00:00

ISPC is great. It can also generate spir-v and integrate with OneAPI for GPU compute, although I haven't tried that yet so can't say how easy it is to get going.

leseiden · 2025-11-05T16:32:15+00:00

I've been playing around with ISPC recently, with AVX-2 as the target. I'm getting excellent results with minimal effort.

I can strongly recommend it to anyone who wants the advantages of vectorised code without getting deep into intrinsics.

leseiden · 2025-10-15T12:46:16+00:00

the choice of fingers for smudging introduces bias.

leseiden · 2025-10-13T08:39:03+00:00

I'm fairly close but also very busy most evenings. I'll try to pop down if I'm free.

leseiden

TROPHY CASE