Add 1-based indexing syntax for connections kw in :mesh3d

src/backends/pgfplotsx.jl

@@ -512,10 +512,26 @@ function pgfx_add_series!(::Val{:heatmap}, axis, series_opt, series, series_func
 end
 
 function pgfx_add_series!(::Val{:mesh3d}, axis, series_opt, series, series_func, opt)
+    if opt[:connections] isa Tuple{Array,Array,Array}
+        # 0-based indexing
         ptable = join(
             [string(i, " ", j, " ", k, "\\\\") for (i, j, k) in zip(opt[:connections]...)],
             "\n        ",
         )
+    elseif typeof(opt[:connections]) <: AbstractVector{NTuple{3, Int}}
+        # 1-based indexing
+        ptable = join(
+            [string(i, " ", j, " ", k, "\\\\") for (i, j, k) in opt[:connections]],
+            "\n        ",
+        )
+    else
+        throw(
+            ArgumentError(
+                "Argument connections has to be either a tuple of three arrays (0-based indexing)
+                    or an AbstractVector{NTuple{3,Int}} (1-based indexing).",
+            ),
+        )
+    end
     push!(
         series_opt,
         "patch" => nothing,

src/backends/plotly.jl

@@ -678,6 +678,7 @@ function plotly_series(plt::Plot, series::Series)
 
         if series[:connections] !== nothing
             if typeof(series[:connections]) <: Tuple{Array,Array,Array}
+                # 0-based indexing
                 i, j, k = series[:connections]
                 if !(length(i) == length(j) == length(k))
                     throw(
@@ -689,10 +690,17 @@ function plotly_series(plt::Plot, series::Series)
                 plotattributes_out[:i] = i
                 plotattributes_out[:j] = j
                 plotattributes_out[:k] = k
+            elseif typeof(series[:connections]) <: AbstractVector{NTuple{3, Int}}
+                # 1-based indexing
+                i, j, k = broadcast(i -> [ inds[i]-1 for inds in series[:connections]], (1, 2, 3))
+                plotattributes_out[:i] = i
+                plotattributes_out[:j] = j
+                plotattributes_out[:k] = k
             else
                 throw(
                     ArgumentError(
-                        "Argument connections has to be a tuple of three arrays.",
+                        "Argument connections has to be either a tuple of three arrays (0-based indexing)
+                         or an AbstractVector{NTuple{3,Int}} (1-based indexing).",
                     ),
                 )
             end

src/backends/pyplot.jl

@@ -700,8 +700,13 @@ function py_add_series(plt::Plot{PyPlotBackend}, series::Series)
 
     if st == :mesh3d
         polygons = if series[:connections] isa AbstractVector{<:AbstractVector{Int}}
+            # Combination of any polygon types
+            broadcast(inds -> broadcast(i -> [x[i], y[i], z[i]], inds), series[:connections])
+        elseif series[:connections] isa AbstractVector{NTuple{N, Int}} where N
+            # Only N-gons - connections have to be 1-based (indexing)
             broadcast(inds -> broadcast(i -> [x[i], y[i], z[i]], inds), series[:connections])
         elseif series[:connections] isa NTuple{3,<:AbstractVector{Int}}
+            # Only triangles - connections have to be 0-based (indexing)
             ci, cj, ck = series[:connections] 
             if !(length(ci) == length(cj) == length(ck))
                 throw(

src/utils.jl

@@ -1180,17 +1180,13 @@ end
 _document_argument(S::AbstractString) =
     _fmt_paragraph("`$S`: " * _arg_desc[Symbol(S)], leadingspaces = 6 + length(S))
 
-function mesh3d_triangles(x, y, z, cns)
+function mesh3d_triangles(x, y, z, cns::Tuple{Array,Array,Array})
-    if typeof(cns) <: Tuple{Array,Array,Array}
     ci, cj, ck = cns
     if !(length(ci) == length(cj) == length(ck))
         throw(
             ArgumentError("Argument connections must consist of equally sized arrays."),
         )
     end
-    else
-        throw(ArgumentError("Argument connections has to be a tuple of three arrays."))
-    end
     X = zeros(eltype(x), 4length(ci))
     Y = zeros(eltype(y), 4length(cj))
     Z = zeros(eltype(z), 4length(ck))
@@ -1214,6 +1210,30 @@ function mesh3d_triangles(x, y, z, cns)
     end
     return X, Y, Z
 end
+function mesh3d_triangles(x, y, z, cns::AbstractVector{NTuple{3, Int}})
+    X = zeros(eltype(x), 4length(cns))
+    Y = zeros(eltype(y), 4length(cns))
+    Z = zeros(eltype(z), 4length(cns))
+    @inbounds for I in 1:length(cns)
+        i = cns[I][1]  # connections are 1-based
+        j = cns[I][2]
+        k = cns[I][3]
+        m = 4(I - 1) + 1
+        n = m + 1
+        o = m + 2
+        p = m + 3
+        X[m] = X[p] = x[i]
+        Y[m] = Y[p] = y[i]
+        Z[m] = Z[p] = z[i]
+        X[n] = x[j]
+        Y[n] = y[j]
+        Z[n] = z[j]
+        X[o] = x[k]
+        Y[o] = y[k]
+        Z[o] = z[k]
+    end
+    return X, Y, Z
+end
 
 # cache joined symbols so they can be looked up instead of constructed each time
 const _attrsymbolcache = Dict{Symbol,Dict{Symbol,Symbol}}()