WebGL 2.0

[kdziamura]

#27

I've started from suggestion to change options interface (it was mixed with canvas context attributes options. From my point of view it’s a bit confusing but I will not insist if the changes are unacceptable) and finished with implementation of WebGL2 support.

[morisil]

@wontem I would like to use your PR, but it does not work with multibuffer shaders

It's because the following invalid shader code is produced:

#define BUFFER_0
#version 300 es

#ifdef GL_ES
precision mediump float;
#endif
...

Which results in:

Error compiling shader [object WebGLShader]:ERROR: 0:2: 'version' : #version directive must occur before anything else, except for comments and white space

[kdziamura]

@morisil the problem is here:
https://github.com/wontem/glslCanvas/blob/0d617cd67b8598d58690bacb7479183bda75e495/src/GlslCanvas.js#L605

I'll look into that today, thanks

[kdziamura]

The problem with buffers is still here. Unfortunately, haven't look into it for a long time and still have no time to work on it 😞