Fragment shader functions not in working order

## *What* is wrong?
I have a problem with a shader. The functions in the shader are not in the correct order. I am trying to add roughly 20 functions, and they are breaking the compiled fragment shader. The problematic shader has some functions defined before functions it depends on, which apparently does not work in webGL. I rearranged the shader functions by hand and it works fine.

## *Where* does it happen?
A website running GPU.js on my desktop Mac mini (specifically this website https://m0ose.github.io/jsSketches/gpgpuTest/index2.html)

## *How* do we replicate the issue?
I put the example webpage here https://m0ose.github.io/jsSketches/gpgpuTest/index2.html , and the source code for it is here https://github.com/m0ose/jsSketches/tree/master/gpgpuTest .
The first time it tries to run the kernel it uses the compiled shader, and throws an error. Then, it sets the shader to the hand edited one(with the functions in a different order) and it works.
Specifically, I had to change the order of these functions to get it to work, https://github.com/m0ose/jsSketches/blob/master/gpgpuTest/reorganizedFragmentShader.js#L473-L531 .
Here is the original runtime compiled shader for reference, https://github.com/m0ose/jsSketches/blob/master/gpgpuTest/originalFragmentShader.js#L540-L545 .

## *How* important is this (1-5)?
𝜋

## Expected behavior (i.e. solution)
I am not sure what is causing this bug. I was not able to extract a smaller example, which might show the problem better. Could it be caused by the function names?

## Other Comments
This is an Amazing library.

Start by running the linked gpgpuTest example and comparing the generated shader with reorganizedFragmentShader.js and originalFragmentShader.js, especially the function ranges referenced in the issue. Trace how GPU.js assembles the fragment shader and reproduce the WebGL compilation failure. Done means the example compiles and runs without manually reordering the functions.

Scritto dal modello di indicizzazione a partire dal testo della issue.