better error messages for plot3d/plot3d! when missing packages

docs/src/lib/interfaces.md

@@ -73,6 +73,13 @@ RecipesBase.apply_recipe(::Dict{Symbol,Any}, ::LazySet{N}, ::N=N(1e-3)) where {N
 RecipesBase.apply_recipe(::Dict{Symbol,Any}, ::AbstractVector{VN}, ::N=N(1e-3), ::Int=40, ::Bool=false) where {N<:Real, VN<:LazySet{N}}
 ```
 
+For three-dimensional sets, we support `Makie`:
+
+```@docs
+plot3d
+plot3d!
+```
+
 ### Set functions that override Base functions
 
 ```@docs

src/Initialization/init_Makie.jl

@@ -1 +1 @@
-eval(initialize_mesh())
+eval(load_makie())

src/Initialization/init_Polyhedra.jl

@@ -29,5 +29,4 @@ end)
 eval(load_polyhedra_hpolytope())
 eval(load_polyhedra_hpolyhedron())
 eval(load_polyhedra_vpolytope())
-
-eval(initialize_mesh())
+eval(load_polyhedra_mesh())

src/Plotting/mesh.jl

@@ -1,14 +1,25 @@
-function load_mesh()
+export plot3d, plot3d!
+
+
+function load_polyhedra_mesh()
 return quote
 
 using .Polyhedra: Mesh
+
+end end  # quote / function load_polyhedra_mesh()
+
+
+function load_makie()
+return quote
+
 using .Makie: mesh, mesh!
-import .Makie.AbstractPlotting: Automatic
+using .Makie.AbstractPlotting: Automatic
+
+end end  # quote / function load_makie()
 
-export plot3d, plot3d!
 
 # helper function for 3D plotting; converts S to a polytope in H-representation
-function plot3d_helper(S::LazySet{N}, backend) where {N}
+function _plot3d_helper(S::LazySet{N}, backend) where {N}
     @assert dim(S) <= 3 "plot3d can only be used to plot sets of dimension three (or lower); " *
         "but the given set is $(dim(S))-dimensional"
 
@@ -24,11 +35,11 @@ end
 
 """
     plot3d(S::LazySet{N}; backend=default_polyhedra_backend(S, N),
-           alpha=1.0, color=:blue, colormap=:viridis, colorrange=Automatic(),
+           alpha=1.0, color=:blue, colormap=:viridis, colorrange=nothing,
            interpolate=false, linewidth=1, overdraw=false, shading=true,
            transparency=true, visible=true) where {N}
 
-Plot a three-dimensional convex set using Makie.
+Plot a three-dimensional convex set using `Makie`.
 
 ### Input
 
@@ -43,9 +54,10 @@ Plot a three-dimensional convex set using Makie.
 - `colormap`     -- (optional, default: `:viridis`) the color map of the main plot;
                     call `available_gradients()` to see what gradients are available,
                     and it can also be used as `[:red, :black]`
-- `colorrange`   -- (optional, default: `Automatic()`) a tuple `(min, max)` where
-                    `min` and `max` specify the data range to be used for indexing
-                    the colormap
+- `colorrange`   -- (optional, default: `nothing`, which falls back to
+                    `Makie.AbstractPlotting.Automatic()`) a tuple `(min, max)`
+                    where `min` and `max` specify the data range to be used for
+                    indexing the colormap
 - `interpolate`  -- (optional, default: `false`) a bool for heatmap and images,
                     it toggles color interpolation between nearby pixels
 - `linewidth`    -- (optional, default: `1`) a number that specifies the width of
@@ -103,17 +115,22 @@ julia> plot3d!(10. * rand(Hyperrectangle, dim=3), color=:red)
 ```
 """
 function plot3d(S::LazySet{N}; backend=default_polyhedra_backend(S, N),
-                alpha=1.0, color=:blue, colormap=:viridis, colorrange=Automatic(), interpolate=false,
+                alpha=1.0, color=:blue, colormap=:viridis, colorrange=nothing, interpolate=false,
                 linewidth=1, overdraw=false, shading=true, transparency=true, visible=true) where {N}
+    require(:Makie; fun_name="plot3d")
+    require(:Polyhedra; fun_name="plot3d")
 
-    P_poly_mesh = plot3d_helper(S, backend)
+    if colorrange == nothing
+        colorrange = Automatic()
+    end
+    P_poly_mesh = _plot3d_helper(S, backend)
     return mesh(P_poly_mesh, alpha=alpha, color=color, colormap=colormap, colorrange=colorrange,
                 interpolate=interpolate, linewidth=linewidth, transparency=transparency, visible=visible)
 end
 
 """
     plot3d!(S::LazySet{N}; backend=default_polyhedra_backend(S, N),
-            alpha=1.0, color=:blue, colormap=:viridis, colorrange=Automatic(), interpolate=false,
+            alpha=1.0, color=:blue, colormap=:viridis, colorrange=nothing, interpolate=false,
             linewidth=1, overdraw=false, shading=true, transparency=true, visible=true) where {N}
 
 Plot a three-dimensional convex set using Makie.
@@ -129,13 +146,15 @@ documentation](http://makie.juliaplots.org/stable/plot-attributes).
 See the documentation of `plot3d` for examples.
 """
 function plot3d!(S::LazySet{N}; backend=default_polyhedra_backend(S, N),
-                alpha=1.0, color=:blue, colormap=:viridis, colorrange=Automatic(), interpolate=false,
+                alpha=1.0, color=:blue, colormap=:viridis, colorrange=nothing, interpolate=false,
                 linewidth=1, overdraw=false, shading=true, transparency=true, visible=true) where {N}
+    require(:Makie; fun_name="plot3d!")
+    require(:Polyhedra; fun_name="plot3d!")
 
-    P_poly_mesh = plot3d_helper(S, backend)
+    if colorrange == nothing
+        colorrange = Automatic()
+    end
+    P_poly_mesh = _plot3d_helper(S, backend)
     return mesh!(P_poly_mesh, alpha=alpha, color=color, colormap=colormap, colorrange=colorrange,
                  interpolate=interpolate, linewidth=linewidth, transparency=transparency, visible=visible)
 end
-
-end # quote
-end # function load_mesh()

src/init.jl

@@ -7,12 +7,6 @@ function __init__()
     @require Polyhedra = "67491407-f73d-577b-9b50-8179a7c68029" include("Initialization/init_Polyhedra.jl")
 end
 
-function initialize_mesh()
-    if isdefined(@__MODULE__, :Polyhedra) && isdefined(@__MODULE__, :Makie)
-       eval(load_mesh())
-    end
-end
-
 """
     require(package::Symbol; fun_name::String="", explanation::String="")