defaultProjectionData.fallbackMatrix and .mainMatrix do not reflect the correct types

[bigmistqke]

I am currently in the process of making the MapLibre-project at my job functional in earlier browser versions. In our project we have a CustomLayer, in which I am passing the defaultProjectionData from its render-function to a glsl shader.

The fallbackMatrix and mainMatrix are typed as mat4, implying they are Float32Array, but in reality they are Float64Array being cast to any to circumvent the types of gl-matrix (see #326 (comment)).

Currently gl.uniformMatrix4fv accepts any Iterable returning numbers, but chrome <68 only accepted Float32Array or Array<number>, causing the CustomLayer to fail when trying to set the uniform.

as #326 (comment) mentioned:

It might be good to consider making a 64bit version/extend glmatrix to play better with Typescript for things like this..

which I agree with. It would be cool if gl-matrix had mat<Float64Array>! Else we could maybe add type annotations in the jsdoc?

The fallbackMatrix and mainMatrix are only 2 examples of this cast, it happens at multiple occasions throughout the codebase.

[HarelM]

Feel free to improve typings.
Since gl-matrix doesn't support this genetics, as far as I know, we use variable names to indicate if this is a 32 or 64.
You could also see if it's possible to open an issue for gl-matrix repo to add support for that...

[bigmistqke]

Hi HareIM

Finally had some time today to have a look at it.
I made an initial draft PR: #6460

[HarelM]

Thanks @bigmistqke
I added a few comments.
I'd also be interested in seeing what the gl-matrix maintainers has to say, maybe just presenting them with the problem statement instead of the proposed solution ti get an unbiased opinion.

[bigmistqke]

I'd also be interested in seeing what the gl-matrix maintainers has to say, maybe just presenting them with the problem statement instead of the proposed solution ti get an unbiased opinion.

Good idea, I will make an issue at their repo.