Can't interpolate between any old OrthogonalSphericalShellGrid and a LatitudeLongitudeGrid

[glwagner]

For example

using Oceananigans
using OrthogonalSphericalShellGrids
using Oceananigans.Fields: interpolate!

trg = TripolarGrid(size = (10, 10, 10), z = (0, 1))
llg = LatitudeLongitudeGrid(size = (10, 10, 10), latitude = (-75, 75), longitude = (0, 360), z = (0, 1))

ctrg = CenterField(trg)
cllg = CenterField(llg)

interpolate!(cllg, ctrg)

fails with

julia> interpolate!(cllg, ctrg)
ERROR: MethodError: no method matching fractional_x_index(::Float64, ::Tuple{…}, ::Oceananigans.Grids.ZRegOrthogonalSphericalShellGrid{…})

Closest candidates are:
  fractional_x_index(::Any, ::Any, ::ImmersedBoundaryGrid)
   @ Oceananigans ~/.julia/packages/Oceananigans/A6YUV/src/ImmersedBoundaries/ImmersedBoundaries.jl:283
  fractional_x_index(::Any, ::Any, ::Oceananigans.Grids.XRegularLLG)
   @ Oceananigans ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:74
  fractional_x_index(::Any, ::Any, ::LatitudeLongitudeGrid)
   @ Oceananigans ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:89
  ...

Stacktrace:
  [1] _fractional_indices
    @ ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:165 [inlined]
  [2] fractional_indices
    @ ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:154 [inlined]
  [3] interpolate
    @ ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:240 [inlined]
  [4] macro expansion
    @ ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:337 [inlined]
  [5] cpu__interpolate!
    @ ~/.julia/packages/KernelAbstractions/3B1v2/src/macros.jl:291 [inlined]
  [6] cpu__interpolate!(__ctx__::KernelAbstractions.CompilerMetadata{…}, to_field::Field{…}, to_grid::LatitudeLongitudeGrid{…}, to_location::Tuple{…}, from_field::Field{…}, from_grid::Oceananigans.Grids.ZRegOrthogonalSphericalShellGrid{…}, from_location::Tuple{…})
    @ Oceananigans.Fields ./none:0
  [7] __thread_run(tid::Int64, len::Int64, rem::Int64, obj::KernelAbstractions.Kernel{…}, ndrange::Nothing, iterspace::KernelAbstractions.NDIteration.NDRange{…}, args::Tuple{…}, dynamic::KernelAbstractions.NDIteration.DynamicCheck)
    @ KernelAbstractions ~/.julia/packages/KernelAbstractions/3B1v2/src/cpu.jl:140
  [8] __run(obj::KernelAbstractions.Kernel{…}, ndrange::Nothing, iterspace::KernelAbstractions.NDIteration.NDRange{…}, args::Tuple{…}, dynamic::KernelAbstractions.NDIteration.DynamicCheck, static_threads::Bool)
    @ KernelAbstractions ~/.julia/packages/KernelAbstractions/3B1v2/src/cpu.jl:107
  [9] (::KernelAbstractions.Kernel{…})(::Field{…}, ::Vararg{…}; ndrange::Nothing, workgroupsize::Nothing)
    @ KernelAbstractions ~/.julia/packages/KernelAbstractions/3B1v2/src/cpu.jl:46
 [10] (::KernelAbstractions.Kernel{…})(::Field{…}, ::Vararg{…})
    @ KernelAbstractions ~/.julia/packages/KernelAbstractions/3B1v2/src/cpu.jl:39
 [11] launch!(::CPU, ::LatitudeLongitudeGrid{…}, ::Tuple{…}, ::typeof(Oceananigans.Fields._interpolate!), ::Field{…}, ::Vararg{…}; include_right_boundaries::Bool, reduced_dimensions::Tuple{}, location::Nothing, active_cells_map::Nothing, kwargs::@Kwargs{})
    @ Oceananigans.Utils ~/.julia/packages/Oceananigans/A6YUV/src/Utils/kernel_launching.jl:168
 [12] launch!
    @ ~/.julia/packages/Oceananigans/A6YUV/src/Utils/kernel_launching.jl:154 [inlined]
 [13] interpolate!(to_field::Field{…}, from_field::Field{…})
    @ Oceananigans.Fields ~/.julia/packages/Oceananigans/A6YUV/src/Fields/interpolate.jl:366
 [14] top-level scope
    @ REPL[8]:1
Some type information was truncated. Use `show(err)` to see complete types.

@simone-silvestri code credit

CliMA/OrthogonalSphericalShellGrids.jl#29