StageGL, low-end android phone exception with latest easeljs-NEXT

[Nestorferrando]

Launching an app based on stageGL on an low-end android device throws the following exception:

Uncaught Cannot compile shader ERROR: 0:1: 'highp' : precision is not supported in fragment shader

[DavidHGillen]

Something not supporting highp is quite low end, that's for sure. There hadn't been any plans to account for it, but it's basically a quality flag. If adjusted too low it will produce artifacts.

I don't have plans yet to support that but I'll consider adding something.

For now the "get it working" patch would be something like the following:

// load StageGL

createjs.StageGL._createShaderORIG = createjs.StageGL._createShader;
createjs.StageGL._createShader = function (gl, type, str) {
    str = str.replace(/highp/g, "mediump");
    return this._createShaderORIG(gl, type, str);
}

// create Stage

[Nestorferrando]

Hi! thanks for considering adding something.

Just for giving more details, the phone GPU is a ARM Mali MP-400. Android version 6.0. The GPU is quite old but still sold on some low-end phones.

I lowered the shader quality to mediump and the game started. Although the performance is not perfect, it is just good enough. The graphics quality seems good enough also.