nixos中的nodejs headless-gl null

Question

我有这个 shell.nix：

with import <nixpkgs> {};
stdenv.mkDerivation {
  name = "env";
  nativeBuildInputs = [ pkg-config ];
  buildInputs = [
    xorg.libX11
    xorg.libX11.dev
    xorg.libXi
    xorg.libXext
    libGL
  ];
}

然后我用nix-shell shell.nix 和

进入shell

$ npm install gl

我认为它构建正确。

我已经使用项目主页 README 中的示例创建了 index.js

// Create context
var width   = 64
var height  = 64
var gl = require('gl')(width, height, { preserveDrawingBuffer: true })

//Clear screen to red
gl.clearColor(1, 0, 0, 1)
gl.clear(gl.COLOR_BUFFER_BIT)

//Write output as a PPM formatted image
var pixels = new Uint8Array(width * height * 4)
gl.readPixels(0, 0, width, height, gl.RGBA, gl.UNSIGNED_BYTE, pixels)
process.stdout.write(['P3\n# gl.ppm\n', width, " ", height, '\n255\n'].join(''))

for(var i = 0; i < pixels.length; i += 4) {
  for(var j = 0; j < 3; ++j) {
    process.stdout.write(pixels[i + j] + ' ')
  }
}

当我运行这个时：

$ node index.js

我收到错误：

\/home/roman/personal_projects/nixos/nixos-headless-gl-error-no-webgl/index.js:20
gl.clearColor(1, 0, 0, 1)
   ^

TypeError: Cannot read property 'clearColor' of null
    at Object.<anonymous> (/home/roman/personal_projects/nixos/nixos-headless-gl-error-no-webgl/index.js:20:4)
    at Module._compile (internal/modules/cjs/loader.js:1085:14)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1114:10)
    at Module.load (internal/modules/cjs/loader.js:950:32)
    at Function.Module._load (internal/modules/cjs/loader.js:790:12)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:76:12)
    at internal/main/run_main_module.js:17:47

Answer 1

有效。现在我已经 run.nix：

with import <nixpkgs> {};
stdenv.mkDerivation {
  name = "env";
  APPEND_LIBRARY_PATH = "${lib.makeLibraryPath [ libGL libuuid ]}";
  shellHook = ''
    export LD_LIBRARY_PATH="$APPEND_LIBRARY_PATH:$LD_LIBRARY_PATH"
  '';
}

和nix-shell run.nix 和

$ nix-shell run.nix
$ echo $LD_LIBRARY_PATH | tr ':' '\n'
/nix/store/hwnjiqml5vvlngdj9nrnwg0qzglhgk2r-util-linux-2.36.2/lib
/nix/store/c35w5n0prvq4v4priyi8fiiq361pmyvp-libGL-1.3.3/lib
/nix/store/a1xkyw98lgj38kymim78a7xjk50wqg6k-telepathy-glib-0.24.2/lib
/nix/store/nzp3cc7bsj83dn23b4vvrvsp9psgg50m-telepathy-logger-0.8.2/lib
$ node index.js
P3
# gl.ppm
64 64
255
255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 255 0 0 
...