[jasmcole]

Good question! This is actually a numerical solver for a few coupled partial differential equations - the method in this context (electromagnetism) is called FDTD. It's implemented as a WebGPU compute shader.

You absolutely could do this using WebGL2 compute shaders too, but I thought it would be fun to try this newer API.

[zorgmonkey]

Annoyingly WebGL2 doesn't have compute shaders even though GLES3.x that it is based on does.

[pjmlp]

Thank Google for that, as they dropped Intel contribution to WebGL Compute, with the reasoning WebGPU would be good enough.

[soheil]

I don't understand what other type of solution is there to render on a gpu other than a numeric one?

Here is a very basic shader for what you want:

  float freq1 = 2.0;
  float freq2 = 3.0;
  float amp = 0.5;

  pos.z += sin(pos.x * freq1 + uTime) * amp;
  pos.z += cos(pos.y * freq2 + uTime) * amp;

  gl_Position = projectionMatrix * modelViewMatrix * vec4(pos, 1.0);

[vardump]

That's no solver, it just displays a sine wave pattern.

[dankwizard]

Did ChatGPT write that for you because it has missed the mark by 500 metres.

[soheil]

It's a sin + cos function.. you need an AI for that?

[_flux]

The point was that the implementation of this tool is not a sin+cos function. It's more like

  let newEz = Ez0[me] +  calcEzDiff(vec2u(id.x, id.y), dx, dy, aspect);

  let newEzAbove = Ez0[above] +  calcEzDiff(vec2u(id.x, id.y + 1), dx, dy, aspect);
  let newEzRight = Ez0[right] +  calcEzDiff(vec2u(id.x + 1, id.y), dx, dy, aspect);

  Hx1[me] = Hx0[me] - (uniforms.dt/mu0)*(newEzAbove - newEz) / dy;
  Hy1[me] = Hy0[me] + (uniforms.dt/mu0)*(newEzRight - newEz) / dx;

  Ez1[me] = newEz;

  let localDelta = delta[me];
  let fac = 1 + uniforms.omega * uniforms.dt * (delta[me] / eps[me] / 2);
  Ez1[me] = Ez1[me] / fac;
  Hx1[me] = Hx1[me] / fac;
  Hy1[me] = Hy1[me] / fac;

and then a bunch of other GPU code. You can find this with little effort from the bundle, if you care, by base64-decoding the Pt("xxx") parts.

Though I do imagine it indeed could be implementable with WebGL shaders, but I also wouldn't start a new compute-based on it, unless I had a particular need to support older systems. And this I say as a Firefox user..