Seriously.js • Hacker News Board

Re: Seriously.js

#191

Post by BHSPitMonkey » Thu, Jun 06, 2013, 6:05 PM UTC

spyder wrote: post #168

tqs wrote: post #107

The technology used here to do the image processing is GLSL, in particular fragment shaders (aka pixel shaders). GLSL is a very small C-like language that's become a standard for GPUs. GLSL code gets sent (as a string) to the GPU by javascript via the WebGL API. Seriously is a JS library for handling the boilerplate of WebGL, composing and compositing multiple shaders in a pipeline/graph, and adjusting their paramete…

https://www.shadertoy.com/browse (WARNING: it can freeze your browser)

Whose idea was it to actually run all those shaders at once? I guess someone just didn't want to store and host some thumbnails?

Re: Seriously.js

#192

Post by mkolodny » Thu, Jun 06, 2013, 6:21 PM UTC

danielweber wrote: post #41

"Sadly, we are unable to get Seriously.js to work on your computer. Sometimes WebGL gets a bit weird with certain graphics hardware and drivers. Please have a look here for more information."

I had the same deal with Chrome on my OSX Mountain Lion. Here's what fixed it for me:

1. Visiting chrome://flags 2. Scrolling down to Disable WebGL, hitting "Enable", and then "Relaunch now" 3. Repeating steps 1 and 2, but hitting "Disable" rather than "Enable".

Re: Seriously.js

#193

Post by ricardobeat » Thu, Jun 06, 2013, 7:35 PM UTC

daeken wrote: post #186

ricardobeat wrote: post #157

Earlier quoted context omitted.

Just draw the frames to a 2D canvas, without clearing it, then back to the background buffer.

You still need to remove the green-screen. This either means an expensive process on the CPU side, or pushing the frame to the GPU to remove it with a shader and then using RTT and rendering that or reading the framebuffer and drawing that to a canvas. Note, it's really not difficult to do this, it's just slightly more complex than the other effects, is all.

The demo is already removing the green-screen, I don't think that's the most expensive part.

Re: Seriously.js

#194

Post by justncase80 » Thu, Jun 06, 2013, 9:34 PM UTC

mshron wrote: post #6

Finally a demo that doesn't make me think "Wow, the web has really caught up to the 1995 desktop!" Maybe if you're already an after-effects wiz this doesn't seem as magical, but it certainly felt like magic to me.

Really? Isn't this just a video with green screen plus shader? I don't understand whats impressive.

Re: Seriously.js

#195

Post by BHSPitMonkey » Thu, Jun 06, 2013, 11:58 PM UTC

moskie wrote: post #50

beggi wrote: post #25

IN JS? This is so cool. Also: fun to compare the raw video to the original: http://www.youtube.com/watch?v=12zJw9varYE :)

Would also be interesting to see if they could recreate the effect of the original video in JS also.

I (very hackishly, but nonetheless) got it to sort of work:

http://imgur.com/a/PQX63#1

It's full of lots of (mostly green) noise because the demo's chroma key algorithm/parameters aren't that good, but it was fun to do!

Re: Seriously.js

#196

Post by daeken » Fri, Jun 07, 2013, 1:17 AM UTC

ricardobeat wrote: post #193

daeken wrote: post #186

Earlier quoted context omitted.

You still need to remove the green-screen. This either means an expensive process on the CPU side, or pushing the frame to the GPU to remove it with a shader and then using RTT and rendering that or reading the framebuffer and drawing that to a canvas. Note, it's really not difficult to do this, it's just slightly more complex than the other effects, is all.

The demo is already removing the green-screen, I don't think that's the most expensive part.

Well no, the demo is removing the green screen but only in the shaders. As I said, this really isn't a big deal, but it does add complexity.