Dear all,

I have an issue when plotting patches with Makie when the field has no spatial variations.

I provide a MWE below. The returned error is `ArgumentError: range step cannot be zero `

if `v=zeros(nel)`

(constant data) . However if `v=rand(nel)`

it works.

I suspect that using `limits=(min_v, max_v)`

is the source of the zero range step (since min_v==max_v). Commenting it disables the errors but also the plot (at least in Jupyter). Anyone has an idea of potential workarounds?

```
using CairoMakie
using Makie.GeometryBasics
function PatchPlotMakie(mesh, v, xmin, xmax, ymin, ymax; cmap = :viridis, min_v = minimum(v), max_v = maximum(v))
f = Figure()
ar = (maximum(mesh.xv) - minimum(mesh.xv)) / (maximum(mesh.xv) - minimum(mesh.yv))
Axis(f[1, 1], aspect = ar)
p = [Polygon( Point2f0[ (mesh.xv[mesh.e2v[i,j]], mesh.yv[mesh.e2v[i,j]]) for j=1:mesh.nf_el] ) for i in 1:mesh.nel]
poly!(p, color = v, colormap = cmap, strokewidth = 0, strokecolor = :black, markerstrokewidth = 0, markerstrokecolor = (0, 0, 0, 0), aspect_ratio=:image, colorrange=(min_v,max_v))
Colorbar(f[1, 2], colormap = cmap, limits=(min_v, max_v), flipaxis = true, size = 25, height = Relative(2/3) )
display(f)
return nothing
end
# Generate data
nel = 4
v = ones(nel)
# v = rand(nel)
xv = [-1. .0 1. -1. .0 1. -1. .0 1.]
yv = [-1. -1. -1. .0 .0 .0 1. 1. 1.]
e2v = [1 2 5 4; 2 3 6 5; 4 5 8 7; 5 6 9 8]
mesh = (xv=xv, yv=yv, e2v=e2v, nf_el=4, nel=nel )
# Call function
PlotMakie(mesh, v, minimum(xv), maximum(xv), minimum(yv), maximum(yv))
```