Apparent error in docs on "transparency"

[benedict-96]

In the docs "Problems with transparency" are described (https://docs.makie.org/stable/explanations/transparency#Problems-with-transparency).

I do obtain the same plot as is shown (overlap of red and blue planes) with GLMakie, but not with CairoMakie. The CairoMakie plot looks like this:

Which is very different from what is shown in the docs.

The error seems to be that the default in the docs has switched from CairoMakie to GLMakie at some point as the corresponding part in the markdown file does not specify CairoMakie as backend in the first case:

Makie.jl/docs/src/explanations/transparency.md

Lines 54 to 73 in 899eeb5

	```@figure
	fig = Figure()
	ax = LScene(fig[1, 1], show_axis=false)
	p1 = mesh!(ax, Rect2f(-1.5, -1, 3, 3), color = (:red, 0.5), shading = NoShading)
	p2 = mesh!(ax, Rect2f(-1.5, -2, 3, 3), color = (:blue, 0.5), shading = NoShading)
	rotate!(p1, Vec3f(0, 1, 0), 0.1)
	rotate!(p2, Vec3f(0, 1, 0), -0.1)
	fig
	```
	```@figure backend=GLMakie
	fig = Figure()
	ax = LScene(fig[1, 1], show_axis=false)
	p1 = mesh!(ax, Rect2f(-1.5, -1, 3, 3), color = (:red, 0.5), shading = NoShading)
	p2 = mesh!(ax, Rect2f(-1.5, -2, 3, 3), color = (:blue, 0.5), shading = NoShading)
	rotate!(p1, Vec3f(0, 1, 0), 0.1)
	rotate!(p2, Vec3f(0, 1, 0), -0.1)
	fig
	```

[jkrumbiegel]

Hm I would have thought the activate! gets spliced in by the code that handles the @figure blocks, but it seems not to have happened there.

Makie.jl/docs/figure_block.jl

Lines 187 to 190 in 899eeb5

	(is_continued ? "" : """
	using $backend
	$backend.activate!(; px_per_unit = 2) # hide
	""") *

[jkrumbiegel]

Aha no the two images are actually the same image, the one from the GLMakie example. The CairoMakie image has been overwritten due to a bug here

Makie.jl/docs/figure_block.jl

Lines 164 to 165 in 899eeb5

	id = string(hash(el.code), base = 16)[1:7]
	el.code = transform_figure_code(el.code; id, page = page.source, pagetitle = title, is_continued, kwargs...)

it didn't take the hash together with the using CairoMakie part, so both blocks have exactly the same file name.