Font / Text error

[zsoerenm]

After some time, I've used GLMakie again.
I tried the following:

using GLMakie
positions = Observable(rand(Point2f, 10))
fig, ax, p = scatter(positions)

However, it seems that there is an error with the font.

Each number is displayed as a box (see figure).
How can I regenerate the font? There is no error thrown.

[SimonDanisch]

Can you try rm(Makie.get_cache_path()) and then restart GLMakie?

[zsoerenm]

Yes, this regenerated the font:

julia> fig, ax, p = scatter(positions)
[ Info: Makie is caching fonts, this may take a while. Needed only on first run!

However, the figure is still outputted with boxes instead of numbers (like in the figure above).

[jkrumbiegel]

Can you try any other previously unused font? Just to check that it's not font-related

[ffreyer]

Checking what image(Makie.get_texture_atlas().data) looks like might also be helpful

[zsoerenm]

I tried a different font:

f = Figure(backgroundcolor = RGBf(0.98, 0.98, 0.98),
           resolution = (400, 200))
ga = f[1, 1] = GridLayout()
Label(ga[1, 1:2, Top()], "Stimulus ratings", valign = :bottom,
           font = "Noto",
           padding = (0, 0, 5, 0))

The output of

image(Makie.get_texture_atlas().data)

looks like this:

BTW:
I've put

"terminal.integrated.env.linux": {
        "LD_PRELOAD": "/usr/lib64/libstdc++.so.6"
    },

into my VSCode settings, because otherwise I run into the following error

libGL error: MESA-LOADER: failed to open radeonsi: /usr/bin/../lib/julia/libstdc++.so.6: version `GLIBCXX_3.4.30' not found (required by /usr/lib/dri/radeonsi_dri.so) (search paths /usr/lib/dri, suffix _dri)
libGL error: failed to load driver: radeonsi
libGL error: MESA-LOADER: failed to open radeonsi: /usr/bin/../lib/julia/libstdc++.so.6: version `GLIBCXX_3.4.30' not found (required by /usr/lib/dri/radeonsi_dri.so) (search paths /usr/lib/dri, suffix _dri)
libGL error: failed to load driver: radeonsi
libGL error: MESA-LOADER: failed to open swrast: /usr/bin/../lib/julia/libstdc++.so.6: version `GLIBCXX_3.4.30' not found (required by /usr/lib/dri/swrast_dri.so) (search paths /usr/lib/dri, suffix _dri)

[ffreyer]

The entries in the texture atlas look pretty weird. Does this generate a normal looking "a"?

using Makie.FreeTypeAbstraction
image(renderface(findfont("Noto"), 'a', 100)[1][:, end:-1:1])

If not maybe rebuilding FreeTypeAbstraction helps?

[zsoerenm]

It works:

using Makie.FreeTypeAbstraction
image(renderface(findfont("Noto"), 'a', 100)[1][:, end:-1:1])

[ffreyer]

But text("a", font = "Noto") renders a box too, right? Can you show me the texture atlas again after that?

Does

img = renderface(findfont("Noto"), 'a', 100)[1][:, end:-1:1]
sdf = Makie.sdistancefield(img, 4, 16)
image(sdf)

look like a blurry "a"?

[zsoerenm]

Yes, text("a", font = "Noto") renders a box in the center of the scene.

Texture atlas again after that:

img = renderface(findfont("Noto"), 'a', 100)[1][:, end:-1:1]
sdf = Makie.sdistancefield(img, 4, 16)
image(sdf)

[SimonDanisch]

Wow, what platform and Julia version is this? Makie.sdistancefield(img, 4, 16) is pure julia code, and seems to be the culprit here...

[ffreyer]

For reference - this is what image(sdf) should look like:

The function is here:
https://github.com/JuliaPlots/Makie.jl/blob/c6931d0c08a929bc1449c8e4dc38a8cf7a396730/src/utilities/texture_atlas.jl#L238-L256

Maybe you can play around with it a bit to see what goes wrong? in_or_out should be a sharp "a" (i.e. with hard edges instead of antialiased ones). sdf() is from https://github.com/JuliaGraphics/SignedDistanceFields.jl I believe. The bug might also be there

[ffreyer]

These white to black rings kinda look like integer overflows to me. Maybe there is an issue with Int or Float16? Maybe it's also worth checking sdistancefield() without the Float16.() at the end?

[zsoerenm]

I've tried julia v1.7.2 and julia v1.7.3

image(in_or_out)

image(Makie.sdf(in_or_out, xres, yres) ./ downsample)

julia> maximum(Makie.sdf(in_or_out, xres, yres) ./ downsample)
24.218729870931817
julia> Float16(maximum(Makie.sdf(in_or_out, xres, yres) ./ downsample))
Float16(3.135e-5)

image(Float16.(Makie.sdf(in_or_out, xres, yres) ./ downsample))

EDIT: Okay there does seem to be an error with Float16:

julia> Float16(4.)
Float16(0.0)

EDIT2: This does work though:

julia> Float16(4f0)
Float16(4.0)

image(Float16.(Float32.(Makie.sdf(in_or_out, xres, yres) ./ downsample)))

The a, however, does not look like in your example

I created an issue at julia: JuliaLang/julia#45528

[ffreyer]

julia> Float16(maximum(Makie.sdf(in_or_out, xres, yres) ./ downsample))
Float16(3.135e-5)

I get

julia> Float16(24.218729870931817)
Float16(24.22)

so I guess that's part of the issue.

Without the Float16 I still get the same plot for 'a'. So I guess there's a bit more to this. Here's the raw output of

img = renderface(findfont("Noto"), 'a', 100)[1][:, end:-1:1]
sdf = Makie.sdistancefield(img, 4, 16) # without Float16 conversion

if you want to continue investigating. in_and_out looks fine to me.

https://gist.github.com/ffreyer/c952fcb74d4529e3b9023e1d151326c6

[zsoerenm]

okay, the culprit does seem to be the LD_PRELOAD. I had to start Julia with the following, because of this error: JuliaGL/GLFW.jl#198 (comment) :

LD_PRELOAD=/usr/lib64/libstdc++.so.6 /bin/julia

With the PRELOAD Float16 returns garbage.
Any hint how to use GLMakie without the LD_PRELOAD is appreciated.

[zsoerenm]

Good news:
I upgraded to Julia v1.8.0beta3 and the error is gone. The LD_PRELOAD is, however, still necessary.

Thanks for all your help!