Head of Rendering @ Pacific Light & Hologram ~30 games/engines/platforms including Fable, Splinter Cell, Total War, Dauntless, No Mans Sky, DeepMind Lab. Lionhead/Microsft, Ubisoft, Google/DeepMind, SEGA, etc. https://donw.io https://github.com/Celtoys/https://bsky.app/profile/donw.bsky.socialhttps://bsky.app/profile/donw.bsky.social/post/3mkxxajgats2aPushed an example of the videos I used to make for clients. This one dates to 2015, adding Shell Mapping to UE4 for Dauntless. Covers why POM failed us, how I improved it, but ultimately why POM was a dead-end. This motivated the UE shader compiler "half instruction count" fix. youtu.be/6f37CFbJ9k003 May 2026 20:02 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mkxxajgats2ahttps://bsky.app/profile/donw.bsky.social/post/3mkvk4sr7gc2fWhatever that site Twitter was renamed to is so depressing. This place is full of life and positivity, in comparison.02 May 2026 21:02 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mkvk4sr7gc2fhttps://bsky.app/profile/donw.bsky.social/post/3mksexil76k27I still can't over the impression that I'm looking at Remotery every time I see a screenshot of the UE profiler 😅01 May 2026 14:52 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mksexil76k27https://bsky.app/profile/donw.bsky.social/post/3mki2whizrk2tThe youngest has started using Roblox and it's pretty disappointing. It was exactly what I thought: an attempt to bring the mistakes of behind-the-scenes game development into popular culture. It worked! And it's wildly successful. Which makes it all the more disappointing. But it *is* old, so...27 Apr 2026 12:26 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mki2whizrk2thttps://bsky.app/profile/donw.bsky.social/post/3mkhlp66qas2vIt's great to see Total War: Rome II do so well these days. I recall spending months boosting engine perf by ~100x (texture-space blend virtual textures ftw) and super-fast on old Intel integrated cards. Gutted when we released with such bad gameplay perf. Whatever CA have done since is awesome 👍27 Apr 2026 07:53 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mkhlp66qas2vhttps://bsky.app/profile/donw.bsky.social/post/3mju4ginu4k2qRemotery is still here, with no real UI changes, functioning on 100s of diverse platforms and form factors... 10 years after I was told you can't build tools for the web because they keep breaking. It's not my achievement, it's a browser industry achievement. I just made the right calls.19 Apr 2026 13:59 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mju4ginu4k2qhttps://bsky.app/profile/donw.bsky.social/post/3mih6cgbw3c25I have a brand spanking new "Loose Lexer/Parser" for C++ that can pull an entire AST from large code bases orders of magnitude faster than a compiler can. Got some good uses for that coming up!😍01 Apr 2026 17:03 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mih6cgbw3c25https://bsky.app/profile/donw.bsky.social/post/3mgl4yj46xs2bHexen gameplay does not age well, unfortunately: infinite spawns with limited resources and endless tracing back between hubs, switches that open unknown doors several hubs away, inaccurate main projectile weapon, it goes on. Heretic is still amazing and Faith Renewed level design is so much fun.08 Mar 2026 20:00 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mgl4yj46xs2bhttps://bsky.app/profile/donw.bsky.social/post/3mgfs7xnqcs2yFor my C# test game I've built a Result type with Roslyn syntax rewriter to get Rust-style error propagation, without simulating via exceptions. I use + or .Value as de-ref/propagate points (unary + is rarely, if ever, used). Builds with a Bazel macro. This honestly feels so incredibly liberating!06 Mar 2026 17:04 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mgfs7xnqcs2yhttps://bsky.app/profile/donw.bsky.social/post/3mg35ulcnnk2elol, I've been enjoying C# recently and evaluating ditching C++ completely for my personal research/game work. In discussion this came up; nice to know the training has picked up some good reviews 😂02 Mar 2026 11:33 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mg35ulcnnk2ehttps://bsky.app/profile/donw.bsky.social/post/3mg33owrfac2eIf I had the time I'd totally reach out to Microsoft to do PC Fable 2. We had it running so we could run the editor tools. It would take some months and it'd be worth adding a content enhancement pass as well, but everybody seems to be screaming for a PC version, even today! It *was* my favourite...02 Mar 2026 10:54 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mg33owrfac2ehttps://bsky.app/profile/donw.bsky.social/post/3mfm5hepa5s2l"The flow of charge, like water" was the most misleading visual aid presented to me in school. I hated it because I couldn't put my finger on inconsistencies I felt, so flunked all the EMF stuff. I already "got" kinetic/potential energy so wires as frictionless cogs in sequence would be amazing.24 Feb 2026 12:16 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mfm5hepa5s2lhttps://bsky.app/profile/donw.bsky.social/post/3mfc2p4mnh22wResearch engineers are wild. This python, conda, torch, cuda, driver, gpu version hell is pretty much as if the last 30 years of contract-engineering never existed. "One you get your env nailed, don't for the love of god upgrade or change it! Be happy it Just Works!"20 Feb 2026 12:00 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mfc2p4mnh22whttps://bsky.app/profile/donw.bsky.social/post/3mf64kgbn4s2mIt's 2026 and people still be using the default Unreal lighting model. Come on, people, your games are starting to look proper bland cookie-cutter; where's the imagination? Meanwhile, in Dreams... fuppin' gorgeous: https://www.youtube.com/watch?v=T0WZl0a-l4U18 Feb 2026 22:22 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mf64kgbn4s2mhttps://bsky.app/profile/donw.bsky.social/post/3mf2hqkp6ak2zHaving to use Color in my day-to-day is almost as bad as a long British winter.17 Feb 2026 11:32 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mf2hqkp6ak2zhttps://bsky.app/profile/donw.bsky.social/post/3meit6p65ws2fAfter playing so many DOOM 1/2 and extended levels I'm now onto Heretic. This is still such an amazingly playable game. There are so many gameplay and level design lessons tucked away in here, although I really hate the "have to traverse the lava and take damage" levels. Lots to learn, lots to not.10 Feb 2026 11:09 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3meit6p65ws2fhttps://bsky.app/profile/donw.bsky.social/post/3meg5qvfhxc27Given the generation I grew up in, a Rugby match isn't a Rugby match without commentary in a strong Borders accent.09 Feb 2026 09:40 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3meg5qvfhxc27https://bsky.app/profile/donw.bsky.social/post/3me2ewssti22gJoin us on a journey through 50 years of computer graphics and help realize the path it never got to take by inventing the missing hardware, math, and algorithms! Lead our build/test/release culture and help make our next-generation devices: https://www.indeed.com/job/seeking-build-infrastructure-engineer-79e53318e94401a004 Feb 2026 17:17 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3me2ewssti22ghttps://bsky.app/profile/donw.bsky.social/post/3md3es4s3u22aBefore the days of SSR, the water of Fable 1 on Xbox used the screen buffer as a texture source, flipping it and warping texture co-ords. Other PS2 games would have done this as well since using the frame buffer as a texture source was trivial on the GS.23 Jan 2026 09:21 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3md3es4s3u22ahttps://bsky.app/profile/donw.bsky.social/post/3mcyy75twp22fBah! Not enough Ulster players being called up for the 6N; they are white hot right now. Don't care about 6N results and fear Farrell is fast becoming a World Cup liability. I mean, Lions tour was awesome, but we were the only country to sacrifice long-term progress for it.22 Jan 2026 10:31 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3mcyy75twp22fhttps://bsky.app/profile/donw.bsky.social/post/3ma6etqhtyk2wI snapshot many things but one I regret not doing is DEV7 for the Adibou games. It was light years ahead of its time: a non-programmer-friendly, high-level custom language with IDE, debugger & integrated asset pipeline. Again; it was French, and I love that I got to witness their technical prowess.17 Dec 2025 09:45 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3ma6etqhtyk2whttps://bsky.app/profile/donw.bsky.social/post/3ma4vkfx3as2jPlaying through Just Cause 3 right now and it's totally brilliant. On the one hand it's gorgeous and fun to zip around everywhere. On the other, despite its impressive open world, it also highlights the astonishing attention to detail GTA 5 had.16 Dec 2025 19:38 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3ma4vkfx3as2jhttps://bsky.app/profile/donw.bsky.social/post/3m7anfqpwhk2k05 Dec 2025 13:58 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3m7anfqpwhk2khttps://bsky.app/profile/donw.bsky.social/post/3m6eochysm22jAh, nice, yet another "wrote a huge chunk of the bloody engine" credit gets marked up as "additional programming." As a contractor/consultant you have much better financial control over your future but don't ever expect to be part of the team. If you want legitimate credit: put it in your contract.24 Nov 2025 11:00 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3m6eochysm22jhttps://bsky.app/profile/donw.bsky.social/post/3m5z7gqvtf22wIt's coming up on 10 years since I added Global Illumination to UE4 for a client and I still feel immensely sad when colourful games don't attempt the same. They lose out on so much warmth and grounding, and also making lighting artist' life much easier. (this particular one was voxel cone tracing)19 Nov 2025 21:34 +0000at://did:plc:z645yjp3otp66os6ardpd5ne/app.bsky.feed.post/3m5z7gqvtf22w