[BUG] GR backend: collision of colorbar_title and colorbar_ticks

[jtschneider]

Details

I have encountered this strange bug when the GR backend is trying to compute the margin of the text between the colorbar ticks and the colorbar title.

Minimal working example:

scatter( rand(10,10),
			zcolor =LinRange(0.05,0.5,10),
			m = (:roma, 0.8, Plots.stroke(1, :green)),
			colorbar_title="Colorbar title",		
		)

Obviously, the colorbar title is stuck inside the ticks for the colorbar. This is only remedied by smaller ticks as can be seen e.g. like that:

scatter( rand(10,10),
			zcolor =LinRange(1,10,10),
			m = (:roma, 0.8, Plots.stroke(1, :green)),
			colorbar_title="Colorbar title",		
		)

This leads me to believe the GR backend has a fixed distance between colorbartitle and ticks.
I suppose this issue can be fixed easily if one knows where to dig into in order to compute the correct distance from ticks and title..

Backends

This bug occurs on ( insert x below )

Backend	yes	no	untested
gr (default)	X
pyplot		X
plotlyjs	X
pgfplotsx		X
unicodeplots		X
inspectdr			X
gaston			X

Versions

Plots.jl version:

(@v1.7) pkg> st Plots
      Status `~/.julia/environments/v1.7/Project.toml`
  [91a5bcdd] Plots v1.25.6

Backend version (]st -m <backend(s)>):

(@v1.7) pkg> st -m GR
      Status `~/.julia/environments/v1.7/Manifest.toml`
  [28b8d3ca] GR v0.63.1

(@v1.7) pkg> st -m PlotlyJS
      Status `~/.julia/environments/v1.7/Manifest.toml`
  [f0f68f2c] PlotlyJS v0.18.8

Output of versioninfo():

julia> versioninfo()
Julia Version 1.7.1
Commit ac5cc99908 (2021-12-22 19:35 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: Intel(R) Core(TM) i7-10610U CPU @ 1.80GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-12.0.1 (ORCJIT, skylake)

[isentropic]

This does not look like gr

[jtschneider]

This does not look like gr

Okay, I'm not sure if my semantics is correct. IMHO, I suppose there is an inadequate calculation for the margin between colorbar_title and ticks implemented in Plots.jl (and not in GR.jl or the GR framework itself)
To be precise, I suppose this fixed margin is the culprid (L940:

Plots.jl/src/backends/gr.jl

Lines 939 to 941 in 46e19d9

	if sp[:colorbar_title] != ""
	rightpad += 4mm
	end

Unfortunately, I don't have the time right now to verify

[jtschneider]

aha I just saw, my problem is self-made with plot size!
In fact, this is a true minimal working example:

scatter( rand(10,10),
	zcolor = LinRange(0.05,0.5,10),
	size=(320,200),
	m = (:roma, 0.8, Plots.stroke(1, :green)),
	colorbar_title="Colorbar title",
)

yields

[drelatgithub]

I am having the exact same issue here. I might be missing something, but I am wondering why this issue is closed, since the MWE clearly shows that the problem persists. Meanwhile, I cannot find any plot attributes under the "colorbar..." category that can set the padding for the colorbar, so I cannot adjust text locations manually.
Currently, I am using the workaround mentioned here, but in my opinion, this should not be the ultimate solution. Therefore, I might suggest reopening this issue.

[t-bltg]

A partial attempt to fix this for GR has been initiated at #4473, but with some limits.

Should we put the colorbar title to the left of the colorbar instead ?