hexbin fails for small cell sizes in CairoMakie

[astertaylor]

For sufficiently small hexbin sizes, the bin is not plotted and no hexes show up. MWE:

using CairoMakie
x=rand(300); y=rand(300)
hexbin(x, y, cellsize=0.01, threshold=0, strokewidth=0.01) # this works
hexbin(x, y, cellsize=0.001, threshold=0, strokewidth=0.01) # here, nothing shows up

This example is slightly contrived (nobody needs bins so small), but the bug is appearing in a separate usecase where the minimum bin size is much larger. What can I do to fix this, and what could be going wrong?

The issue does not arise in the GLMakie backend...

Running Makie 0.22.1, the error still arises in a fresh environment. Running on Ubuntu 24.04.

[astertaylor]

After further investigation, I've determined that this is actually an issue with scatter. Specifically, for sufficiently small marker sizes, scatter fails to plot anything. Once again, this is only in CairoMakie.

[asinghvi17]

Do you have an MWE for that behavior?

[ffreyer]

Probably this then?

Makie.jl/CairoMakie/src/primitives.jl

Line 370 in d77c537

(abs(det(jl_mat)) < 1) && return

Reducing this will probably cause issues in tests:
#4663 (comment)

Also we had a isapprox(markersize, 0) && return before with a comment that letting it through breaks Cairo state, so something like the det() or this should continue to be there.