notes from the bigfug » PatchBox

Latest PatchBox Pictures: Geometry Shader Shadow Volumes

Alex May — Sun, 21 Mar 2010 03:56:39 +0000

I?ve been getting into writing CGFX geometry shaders! The following couple of pictures are generated inside PatchBox by passing in a simple flat grid of triangles. The geometry shader turns them into cubes and calculates the shadow volumes on the fly. Perhaps not the fastest solution, though my (getting long in the tooth) 8800 can still animate 900 cubes at 60fps.

These development pictures are rather lovely in themselves, and may end up being an installation, though I have further, much more complicated, plans for all this.

Twitter Updates for 2009-09-13

Alex May — Sun, 13 Sep 2009 11:21:00 +0000

Had two weird dreams last night 1) where I was showing short films by other people (but I’d dreamt them), 2) dinner with @ianvisits ! #
Morning spent messing about with projectively texturing cubemaps onto other geometry with light matrices. Now back to work on proposals… #
@ianvisits Yeah, tell me about it! in reply to ianvisits #
@nicklevine Heh, I can’t make it either now! Let the organisers know and I guess they’ll redistribute them to the waiting list… in reply to nicklevine #
Today, I will mostly be driving a van full of boxes down to Wiltshire #
Back from Wiltshire. Got caught behind a steam traction engine for many, many miles. Someone buy them a nice Peugeot or something… #
Is it just me or is the Windows desktop, and all other OS’ variations, completely useless and outmoded as a concept? #
Braid only ?3.39 on steampowered.com – yay. kerching… #
Enjoyed ‘District 9′ the other day, ‘Monsters vs Aliens’ not so much… #
@Flares Assume you’re talking about District 9, not Monster vs Aliens in reply to Flares #
Rewriting PatchBox’s COLLADA loader using the COLLADA DOM: http://bit.ly/19oNLr #

PatchBox: 3D Geometry Scanner

Alex May — Mon, 07 Sep 2009 14:52:34 +0000

We?ve been keeping it under our hats for a while now but the code is nearing completion so it?s time to reveal one of the latest major features we?ve been adding to PatchBox: 3D Scanning.

The image above was created using one projector and one camera resulting in a 300,000 point cloud.? We haven?t smoothed this geometry yet, which is why it?s all bumpy ? it?s the raw feed from the system.? The large holes were in shadow, or were non-reflective such as the monitor screen.? The small holes (such as those on the keyboard) are caused by scanning errors larger than 1cm.

As well as taking stylised self portraits (!), we?ll be using this technology to perform dynamic projective geometry and a myriad of other real-time visual tricks that we?ve been planning for years.

The 3D scanning and associated camera/projector calibration systems are also extremely useful for correctly projecting on curved and other non-planar screens.

Twitter Updates for 2009-09-06

Alex May — Sun, 06 Sep 2009 11:21:00 +0000

Writing some laser tracking code. That’s right, tracking frickin’ LASERS! #
Taken drawing perspective chessboards to new depths (hah). My homography is strong. #
Passing through a downpour at Haywards Heath, heading to London to meet, and demo PatchBox to, The Darkroom #
Burger and beers on the night train heading south. Good to catch up with the Belle Atmos boys and hear the new album, albeit sans vocals. #
RT @shitmydadsays: “It’s just a fucking june bug, calm down. Jesus Christ, what happens when something bigger than a testicle attacks you?” #
Just scanned my head. In 3D! #
Been learning about Delaunay triangulation. Now my front brain is full. Fortunately, Friday eve is all about the lizard cortex. To Brighton! #
Crashed the dConstruct party at Audio. Not sure my particular brand of geek’ness works with the geek mainstream. Ah well, cocktails saved. #
This evening should be drawing to a close and yet am in a taxi heading to Middle Farm for a ‘field party’… #
We were walking the five miles back but instead got a lift from a kind police man. Thanks, PC? #

Live feed video mapping in PatchBox

Alex May — Tue, 01 Sep 2009 15:04:07 +0000

We?re heavily focussed, if you will excuse the pun, on camera and projector calibration at the moment.? The images above are a live video feed taken by a camera that has been calibrated to the geometry of the room that it is filming and reprojected onto the model?s geometry (!).

Twitter Updates for 2009-08-30

Alex May — Sun, 30 Aug 2009 11:21:00 +0000

Busy days ahead for Quadratura. Off to vbites this morning to adjust some veg, London tonight, perhaps Bath at the end of the week. #
Vbites veg up and running (power cut?) Must install a big red reset button. Heading back to work on the new PatchBox boardroom demo. #
Two very interesting meetings in London. Doing a little people watching at Victoria before heading back to Lewes. Much to chew over. #
@StephenBrighton Oh, thanks for that. In t’diary! in reply to StephenBrighton #
Sitting in the beer garden of the Lion and Lamb in Bath. Just been to see the egg room. Serious geometry correction required. Go PatchBox! #
Pretty sure I’ve reached that important “bored of being hungover” stage of the break-up. Let the healing begin! #
@jimonlight Moon is really good, if you can find it. Just listening to the soundtrack now, which is also excellent. in reply to jimonlight #
@nicklevine Yeah, got my ticket online. Must remember to print that sucker out… in reply to nicklevine #
Ignoring the nice bank holiday weather for a few hours, instead working on video camera 3d re-projection… #
Very nice cream teas in Glynde, but the service is so slow as to be almost static (5 tables full constitutes a ‘rush’ apparently…) #
Reminded what Lewes can be on a Saturday night: trapped between worlds of “not want” and being told you have a moviestar face by strange men #

Twitter Updates for 2009-08-23

Alex May — Sun, 23 Aug 2009 11:21:00 +0000

Back at Martin’s after driving around London checking the seven sites we’re planning to cover in video projections tomorrow night. #
Finished the final route plan for tomorrow. Time for an early night – is going to be a long day! #
Drinking coffee and making video content for tonight’s projections. Will be posting up live images and GPS coordinates between 10pm and 2am! #
All the video assets are now prepared, time to pack up the equipment. 2.5 hours to go – feeling excited and nervous. Need to shave… #
Equipment packed, press release prepared for tomorrow morning, food time shortly, still need to shave… #
15 minutes until we set off on this night of visual madness. Martin’s got the car, waiting on our van driver. Strong coffee is brewing… #
Bit of a delay getting going but on the road heading to first site. #
Hit some bad traffic, joy… 51.511077,-0.108852 #
First site: Banksy rat near Barbican #
http://twitpic.com/eafo3 – Banksy 1 #
On our way to second site… #
@vvarp 5 to go in reply to vvarp #
http://twitpic.com/eakf6 – Banksy 2… #
http://twitpic.com/eaq09 – Codefc graffiti #
http://twitpic.com/earpb – No Graffiti No Problems #
And unfortunately, that’s our lot. Batteries drained and the inverter couldn’t cope. Bit sad but we got most of them… #
@vvarp Yep, on the ungraffitiable surface in reply to vvarp #
Higher resolution photos from tonight are up at – http://bit.ly/adsIe – #streetart #banksy #
Press release and photos sent. 4am… SERIOUSLY time to get some sleep… night all, thanks for following! #
Our video that we filmed during last night’s video street art event is now available. Enjoy! http://bit.ly/adsIe #
@chrisbillett We’re setting up a wiki which will have in reply to chrisbillett #
@chrisbillett Oops, yes, the wiki isn’t available yet, but will let you know. What info were you after? in reply to chrisbillett #
Went to the Farrah Azam Fortnam exhibition opening last night at The Muse, Portobello Road. Now drinking coffee, planning return to Lewes. #
@chrisbillett Will keep you posted. Also we’re just updating the live demo that’ll feature most of our mapping tricks, if that’s of interest in reply to chrisbillett #
Back in Lewes. Hell’s teeth, it’s hot today. Almost hot enough to contemplate a lunchtime Staropramen. Might have sleepy consequences though #
RT @alpaykasal: RT @pinkninjatweets: “chair” Videoart Projection by Masaru Ozaki http://bit.ly/SHS4R #
Heading to Brunswick Square Festival in Brighton to meet up with London chums. Might need some cheap yet jaunty sunglasses. #

Twitter Updates for 2009-08-16

Alex May — Sun, 16 Aug 2009 11:21:00 +0000

Little bit blind (temporarily, hopefully) after projecting video onto his eyes on purpose. Ah R&D, it’s sometimes a dangerous business… #
Possible to use modified pyramid image segmentation with canny edge detection to fill in the holes? Would depend on input quality, I guess.. #
Listening to Tower of Power and downloading my brain into FreeMind. #
Ouch, just got hit in the head by a falling Dell Axim 51v with large capacity battery. Better my head than the floor, I guess… #
Experimenting with MS Speech API by playing the audio from Dr Strangelove into the recogniser. Mildly amusing but ultimately useless results #
Just hit a large roll of graph paper with my fist. In your FACE graph paper! #
Deep into planning our first guerrilla video projection session in London on Monday night… Mwahaha… #
@vj_anomolee All will be revealed in good time, my friend… in reply to vj_anomolee #
Mmm, 2pm – must be time for breakfast, yay! #
@nicklevine Good find! See you there! in reply to nicklevine #
The team is prepped for Monday night. Four men, in a van, with advanced technology, and mischief in mind. #
@nicklevine Will do, chap! in reply to nicklevine #
@StephenBrighton Like the look of the Iydea photo exhibition – is there a private view/event? #
@StephenBrighton Very kind of you, thanks! in reply to StephenBrighton #
Heading to Brighton to check out new exhibition at Prescription Art, followed by racking up the uncomfortably weird dial to 11. #
Listening to the recording of the last Belle Atmos gig – shame we didn’t get footage of the visuals, says visuals man: http://bit.ly/18bXlq #
@nicklevine Haven’t been up so much of recent since last job was in Hove but we’ve meetings in town a plenty coming up. in reply to nicklevine #
Going to have to refactor a large chunk of PaintBox – needs a floating point drawing buffer to get the nuance I need! #
Oh, that was easier than I expected then! Just got to add a cursor on the streamed output and it’ll be ready to go… #
Dammit, seemed to have messed up my nice Bresenham implementation. Just can’t leave things alone, me… #
@StephenBrighton Lovely, thanks again. in reply to StephenBrighton #
With a couple of hints from Ramesh Raskar I’ve finally got augmented geometry alignment working in PatchBox. Super yay! #
Projective alignment and projection working, off shortly to Lighthouse to see work and talk by Tina Gonsalves in #Brighton #

Twitter Updates for 2009-08-09

Alex May — Sun, 09 Aug 2009 11:21:00 +0000

Still working on winter exhibition plan – hard going trying to balance technology, cost, and artistic cohesiveness! #
Seem to keep coming up with ideas involving Slinky springs… dear god, man, why? #
Saw a gull killing a pigeon in the road. Since the introduction of gull-proof bins here, they’re getting deadlier! Where’s Tippi? #brighton #
Where will you be at 07/08/09 – 10:11:12? http://bit.ly/2w6uS4 #
@grahamblanca +1 hour, minute, and second, of course. Falls over after 11/12/13 14:15:16… Ok, will stop now in reply to grahamblanca #
@grahamblanca Not taking into account leap years, either! in reply to grahamblanca #
@grahamblanca Um, off the top of my head, 01/01/10 – 01:10:10? in reply to grahamblanca #
@grahamblanca Of course, if you add milliseconds into the picture, you can have 01/01/2010 01:02:10.10… Though I prefer the binary one! #
Horrid dreams of orange Smart Cars and yelling leave me feeling lethargic and weird, also today’s jobs: clearing up dog mud and dead mice. #
The default icon for VLC is a traffic cone – makes browsing my media collection feel like travelling the M25 in roadworks season… #
Time to re-install the car speaker I have cleverly (tbc) fixed with the liberal application of copydex! #
@BrightonArgusJo Sounds like a good idea. Afraid I didn’t get any juicy pictures – was driving at the time! in reply to BrightonArgusJo #
Finally got perspective correct texturing working in PatchBox’s quad’s, fixed a few other minor bugs, added bezier curves to PaintBox. Yay. #
Woke with a head full of ideas. Time to get this proposal finished. #
Proposal for winter show finally done. Off to Brighton shortly to make guacamole for tonight’s MEXICAN FEAST! Tortillas! Tequila! ARRIBA! #
Today I will mostly be playing fallout3… #

PatchBox Particles

Alex May — Thu, 23 Jul 2009 00:52:12 +0000

In the process of adding PhysX particles into PatchBox

Rough spheres bouncing off a plane.

Checking billboard alignment.

Texture mapped billboards.