How to enable GLSL extensions like `OES_standard_derivatives`?

[Tom Beddard]

Feature

How to enable GLSL extensions like OES_standard_derivatives?

library version

├── gl-react@3.15.0
└── gl-react-dom@3.15.0

Expected behavior

I tried using the onContextCreate function of the gl-react-dom Surface which exposes the gl instance to enable the extension via gl.getExtension('OES_standard_derivatives')

Actual behavior

Assigning a custom function to onContextCreate actually silently prevents any rendering from happening!

Is there another way to enable additional WebGL extensions?

Thx

[Andrew Bryson]

Hi @subblue

Had the same issue as yourself.

This worked however:

    const gl = ref.glView.canvas.getContext('webgl');
    gl.getExtension('OES_standard_derivatives');

With "ref" being the Surface element's ref.

[Tom Beddard]

Thanks @brysonandrew, good to know that works.
In the end I found a way to do what I needed without the derivatives extension, but good to know for the future 👍

[Andrew Bryson]

Very welcome @subblue sir. Your question helped me find the solution.

[Andrew Bryson]

BTW the above works with gl-react-dom

For a Surface from gl-react-expo, onCreateContext will work.

[Cory Efird]

@brysonandrew Thanks for the tip, but where exactly do you run this code?

I've tried in componentDidMount() and the surfaces preLoad() callback but I'm still getting the error that the extension is not supported.

[Andrew Bryson]

@efirdc You're welcome, yes, componentDidMount.

Here is a gist of the whole component

Do you have something like this is your shader -

#ifdef GL_OES_standard_derivatives
  #extension GL_OES_standard_derivatives : enable
#endif

?