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Re: [Public WebGL] off-line opengl render?



I wrote something to render print resolution images with WebGL a while ago. Its hacky and extremely ugly but it served the purpose.

http://chrysaora.com/
1.click on the "stop" link at the top to pause animation
2.enterÂcaptureCanvas(10240,10240,1024);

The result will be a 10K image rendered as 1K buckets. Most time is spent in jpeg encoding and everything is stored in DOM elements. Did I mention its ugly? :)

The bucket division and rendering logic is here:
http://chrysaora.com/js/imageCapture.js

I'm using Vlad's mjsÂlibraryÂfor projection matrices and I added a custom perspective projector withÂfrustumÂoffsets for the buckets:
http://chrysaora.com/js/lib/mjs.js

--
Aleksandar RodiÄ
http://www.aleksandarrodic.com
+1 510 761 5522



On Tue, Jun 19, 2012 at 10:20 AM, Florian BÃsch <pyalot@gmail.com> wrote:
On Tue, Jun 19, 2012 at 12:31 PM, Tom Sparks <tom_a_sparks@yahoo.com.au> wrote:
I don't know if my local webgl runtime can deal with large images, but then there are limitation with url length
ÂAll WebGL implementations support 2048x2048 and most (91%) support 4096x4096.
You don't need dataURL, you can obtain the image rendered if you attach a texture to an FBO and perform a readPixels from the FBO, you will get a typed Uint8Array back.
Upload to your server can be done with XHR2 that can transmit binary data, so no expensive conversion to base64 or the like required.