add ability for meshes with 3d texture

[SimonDanisch]

So, that one can e.g. make a cut plane into a volume...

[MakieBot]

Compile Times benchmark

Note, that these numbers may fluctuate on the CI servers, so take them with a grain of salt. All benchmark results are based on the mean time and negative percent mean faster than the base branch. Note, that GLMakie + WGLMakie run on an emulated GPU, so the runtime benchmark is much slower. Results are from running:

using_time = @ctime using Backend
# Compile time
create_time = @ctime fig = scatter(1:4; color=1:4, colormap=:turbo, markersize=20, visible=true)
display_time = @ctime Makie.colorbuffer(display(fig))
# Runtime
create_time = @benchmark fig = scatter(1:4; color=1:4, colormap=:turbo, markersize=20, visible=true)
display_time = @benchmark Makie.colorbuffer(display(fig))

	using	create	display	create	display
GLMakie	–	–	–	–	–
master	–	–	–	–	–
evaluation	–	–	–	–	–
CairoMakie	3.05s (3.02, 3.10) 0.03+-	319.92ms (316.56, 327.38) 4.09+-	140.21ms (139.01, 142.47) 1.37+-	7.19ms (7.07, 7.31) 0.09+-	615.80μs (608.61, 621.58) 3.84+-
master	3.06s (3.00, 3.10) 0.03+-	321.54ms (316.96, 328.57) 4.25+-	143.11ms (139.03, 156.75) 6.37+-	7.26ms (7.19, 7.37) 0.06+-	619.40μs (616.60, 627.00) 3.50+-
evaluation	1.00x invariant, -0.01s (-0.35d, 0.53p, 0.03std)	1.01x invariant, -1.61ms (-0.39d, 0.48p, 4.17std)	1.02x invariant, -2.9ms (-0.63d, 0.28p, 3.87std)	1.01x invariant, -0.07ms (-0.96d, 0.10p, 0.08std)	1.01x invariant, -3.6μs (-0.98d, 0.09p, 3.67std)
WGLMakie	3.65s (3.60, 3.71) 0.04+-	320.87ms (315.87, 338.10) 7.78+-	8.87s (8.69, 9.07) 0.15+-	9.14ms (9.02, 9.46) 0.15+-	71.41ms (68.14, 81.26) 4.71+-
master	3.68s (3.64, 3.73) 0.03+-	322.91ms (317.76, 335.02) 7.44+-	8.80s (8.66, 8.96) 0.09+-	9.69ms (8.94, 13.71) 1.77+-	74.28ms (68.00, 80.28) 5.06+-
evaluation	1.01x invariant, -0.02s (-0.71d, 0.21p, 0.03std)	1.01x invariant, -2.04ms (-0.27d, 0.62p, 7.61std)	0.99x invariant, 0.07s (0.57d, 0.31p, 0.12std)	1.06x noisy🤷‍♀️, -0.56ms (-0.44d, 0.44p, 0.96std)	1.04x invariant, -2.88ms (-0.59d, 0.29p, 4.89std)