What does HackerNews think of glm?

C++23: The Next C++ Standard | Jul 2023

Corrected link:

Eigen: A C++ template library for linear algebra | Apr 2022

glm is also good for 3d math. It mimics the API of OpenGL shaders, so it's a good option if you already know how to write shaders (or are interested in learning).

https://github.com/g-truc/glm

WebGL: 80.000 particles | Apr 2015

I did some emscripten/WebGL performance tests a while ago which went into the hundred-thousands particles for 3D-shape-particles at 60fps, but this depends very much on the target hardware, less on the browser or operating system.

Both tests use simple 3D shape particles (5-vertex diamonds) and hardware-instanced rendering (instanced_arrays extension), the first updates particle positions on the CPU, the second on the GPU (fragment shader writes particle position to offscreen render target, which is then sampled in vertex shader to displace particle positions).

The first (CPU updates) goes up to around 450k particles on my Windows7 desktop machine before consistently dropping below 16ms per frame, the second (GPU updates) goes to about 800k particles before dropping below 60fps:

http://floooh.github.io/oryol/Instancing.html

http://floooh.github.io/oryol/GPUParticles.html

These numbers are not much different then using desktop GL (2.1 with extensions). The real advantages for this type of scenario would come from updating persistently mapped buffers which are not available in WebGL.

What's impressive is the raw math performance of asm.js, the particle update loop is simple glm code (https://github.com/g-truc/glm) without any fancy optimizations.