ShaderAbstractions.Buffer in Mesh doesn't change the plot if value is changed in the buffer

[koehlerson]

• [ x ] what version of Makie are you running? (]st -m Makie)
  • v0.21.16
• [ x ] can you reproduce the bug with a fresh environment ? (]activate --temp; add Makie)
  • yes
• [ x ] What platform + GPU are you on?
  • linux, nvidia geforce gt 640

I want to use a ShaderAbstractions.Buffer to update positions of a GeometryBasics.Mesh. If the following is typed in the REPL, the position remains the same for the first vertex in the plot

MWE:

vertices = Point2f[(0.0, 0.0), (1.0, 0.0), (1.0, 1.0), (0.0, 1.0)]
vertices_buf = Buffer(vertices)
triangles = [1, 2, 3, 3, 4, 1]
triangles = Makie.to_triangles(triangles)
colors = [:red, :green, :blue, :orange]
gmesh = GeometryBasics.Mesh(vertices_buf, triangles)
f, ax, pl = mesh(gmesh, color=colors, shading=NoShading)
vertices_buf[1] = Point2f(-1, -1)

@SimonDanisch suspects something in the float64->float32 conversion pipeline that strips away the Buffer