Error creating WebGLContext on Raspberry Pi

[flimshaw]

After installing the pre-reqs, everything built perfectly on the raspberry pi 3, but I get errors trying to create a webgl context. Is operation on embedded platforms like the raspi possible?

I'm getting the following error:

pi@betty:~ $ noisemaker -o test.png
/usr/lib/node_modules/noisemaker/node_modules/headless-gl/index.js:39
  var gl = new webgl.WebGLRenderingContext(
           ^

Error: Error creating WebGLContext
    at Error (native)
    at createContext (/usr/lib/node_modules/noisemaker/node_modules/headless-gl/index.js:39:12)
    at Object.<anonymous> (/usr/lib/node_modules/noisemaker/index.js:37:34)
    at Module._compile (module.js:413:34)
    at Object.Module._extensions..js (module.js:422:10)
    at Module.load (module.js:357:32)
    at Function.Module._load (module.js:314:12)
    at Function.Module.runMain (module.js:447:10)
    at startup (node.js:148:18)
    at node.js:405:3

Trying to install and use this npm library: https://www.npmjs.com/package/noisemaker

Thanks a lot, wonderful library!

[samelie]

increasing GPU memory to 128 solved this.
Running this before node in the same shell also let me use the library as an npm module:

sudo apt-get install xvfb
Xvfb :1 -screen 0 1024x768x24 </dev/null &
export DISPLAY=":1"

[adddog]

Here is a compiling script for FFMPEG on RP3.

If anyone is interested in piping combining regl with headless-gl in node and piping it into ffmpeg. Have a look at this very_development repo.

This pseudo code is to get the input of ffmpeg to be

 var args = [
    "-f",
    "rawvideo",
    "-pix_fmt",
    "rgba",
    "-s",
    `${options.w}x${options.h}`, // eg: 288x156 (size of regl context)
    "-i",
    "-",
  ]

Write rgba in: ffmpeg.stdin.write(rgbaData, function(err) {}) where ffmpeg is a child_process

And somewhere there is a read on the gl context:
read: (width, height) => gl.read(new Uint8Array(width * height * 4)), // returns rgba data

[SunXinFei]

increasing GPU memory to 128 solved this. Running this before node in the same shell also let me use the library as an npm module:

sudo apt-get install xvfb
Xvfb :1 -screen 0 1024x768x24 </dev/null &
export DISPLAY=":1"

good job