Adjusted the automated node placement

NEWS.md

@@ -1,5 +1,12 @@
 # Release notes
 
+## Unversioned (2026-05-19)
+
+### Adjustments
+
+* If coordinates have not been saved to a design file for the nodes under an `Area`, they are now placed *symmetrically* around the circle (that is, accounting for one node being the `GeoAvailability` node to be placed at the center).
+* The default value for the radius of the circle for placing nodes without coordinates is now a third of the minimal distance between area coordinates defined in the `top_level` design file.
+
 ## Version 0.7.1 (2026-04-24)
 
 ### Bugfix

src/setup_topology.jl

@@ -44,12 +44,42 @@ function EnergySystemDesign(
         Dict()
     end
 
+    # Complete the `id_to_color_map` if some products are lacking (this is done by choosing
+    # colors for the lacking `Resource`s that are most distinct to the existing set of colors)
+    if !issubset(get_products(system), keys(id_to_color_map))
+        id_to_color_map = set_colors(get_products(system), id_to_color_map)
+    end
+
+    # Initialize components and connections
+    components = EnergySystemDesign[]
+    connections = Connection[]
+
+    # Create an iterator for the current system
+    elements = get_children(system)
+
+    # Calculate radius for node placement if system is a SystemGeo (i.e. contains geographical information)
     if isa(system, SystemGeo)
-        # Collect all (lon, lat) coordinates from elements that have them
-        coords = [
-            Point2f(element.lon, element.lat)
-            for element ∈ get_children(system)
-        ]
+        coordinates_missing = false
+        coords = Point2f[]
+        for element ∈ elements
+            # Extract available information from file (stored in the `design_dict` variable)
+            key::String = string(element)
+            system_info::Dict = haskey(design_dict, key) ? design_dict[key] : Dict()
+            if haskey(system_info, "x") && haskey(system_info, "y")
+                xy = Point2f(system_info["x"], system_info["y"])
+                push!(coords, xy)
+            else
+                coordinates_missing = true
+                break
+            end
+        end
+        if coordinates_missing
+            # Collect all (lon, lat) coordinates from elements that have them
+            coords = [
+                Point2f(element.lon, element.lat)
+                for element ∈ get_children(system)
+            ]
+        end
 
         # Compute all pairwise distances
         min_dist = Inf
@@ -66,19 +96,6 @@ function EnergySystemDesign(
         radius = min_dist / 3
     end
 
-    # Complete the `id_to_color_map` if some products are lacking (this is done by choosing
-    # colors for the lacking `Resource`s that are most distinct to the existing set of colors)
-    if !issubset(get_products(system), keys(id_to_color_map))
-        id_to_color_map = set_colors(get_products(system), id_to_color_map)
-    end
-
-    # Initialize components and connections
-    components = EnergySystemDesign[]
-    connections = Connection[]
-
-    # Create an iterator for the current system
-    elements = get_children(system)
-
     design = EnergySystemDesign(
         system,
         id_to_color_map,
@@ -99,6 +116,11 @@ function EnergySystemDesign(
     if !isnothing(elements)
         current_node::Int64 = 1
         nodes_count = length(get_children(system))
+        if !isa(parent, NothingDesign) && isa(get_system(parent), SystemGeo)
+            # If the parent is a SystemGeo, we subtract one to the nodes count to account 
+            # for the availability node that is placed in the center
+            nodes_count -= 1
+        end
 
         # Loop through all components of `system`
         for element ∈ elements

src/utils_gen/structures_utils.jl

@@ -15,13 +15,13 @@ function installed()
 end
 
 """
-    place_nodes_in_circle(total_nodes::Int64, current_node::Int64, r::Float32, c::Point2f)
+    place_nodes_in_circle(n::Int64, i::Int64, r::Float32, c::Point2f)
 
 Return coordinate for point number `i` of a total of `n` points evenly distributed around
 a circle of radius `r` centered at `c` from -π/4 to 5π/4.
 """
 function place_nodes_in_circle(n::Int64, i::Int64, r::Float32, c::Point2f)
-    θ::Float32 = n == 1 ? π32 : -π32 / 4 + 3π32 / 2 * (1 - (i - 1) / (n - 1))
+    θ::Float32 = n == 1 ? π32 : -π32 / 4 + 3π32 / 2 * (1 - Float32(i - 1) / Float32(n - 1))
     return c + r * Point2f(cos(θ), sin(θ))
 end