Render result to png after every routing

Pathfinding/Pathfinder.cs

@@ -1,5 +1,6 @@
 using OSMDatastructure;
 using OSMDatastructure.Graph;
+using RenderPath;
 using static OSMDatastructure.Tag;
 using WayType = OSMDatastructure.Tag.WayType;
 
@@ -28,7 +29,14 @@ public static class Pathfinder
         {
             OsmNode currentNode = openSetfScore.Dequeue();
             if (currentNode.Equals(goalNode))
-                return GetPath(cameFromDict, goalNode, regionManager);
+            {
+                List<PathNode> path = GetPath(cameFromDict, goalNode, regionManager);
+                List<Coordinates> coords = new();
+                foreach(PathNode pn in path)
+                    coords.Add(pn.coordinates);
+                Renderer.DrawLoadedNodes(gScore, coords, workingDir);
+                return path;
+            }
 
             foreach (OsmEdge edge in currentNode.edges)
             {

Pathfinding/Pathfinding.csproj

@@ -8,6 +8,7 @@
 
     <ItemGroup>
       <ProjectReference Include="..\OSMDatastructure\OSMDatastructure.csproj" />
+      <ProjectReference Include="..\RenderPath\RenderPath.csproj" />
     </ItemGroup>
 
 </Project>

RenderPath/RenderPath.csproj

@@ -6,12 +6,12 @@
         <Nullable>enable</Nullable>
     </PropertyGroup>
 
-    <ItemGroup>
-      <ProjectReference Include="..\Pathfinding\Pathfinding.csproj" />
-    </ItemGroup>
-
     <ItemGroup>
       <PackageReference Include="System.Drawing.Common" Version="7.0.0" />
     </ItemGroup>
 
+    <ItemGroup>
+      <ProjectReference Include="..\OSMDatastructure\OSMDatastructure.csproj" />
+    </ItemGroup>
+
 </Project>

RenderPath/Renderer.cs

@@ -1,5 +1,4 @@
 using System.Diagnostics.CodeAnalysis;
-using Pathfinding;
 using System.Drawing;
 using System.Drawing.Imaging;
 using OSMDatastructure.Graph;
@@ -9,13 +8,17 @@ namespace RenderPath;
 public class Renderer
 {
     [SuppressMessage("Interoperability", "CA1416:Plattformkompatibilität überprüfen")]
-    public static Bitmap DrawFromPath(List<PathNode> nodes)
-    {
-        float minLat = nodes.Min(node => node.coordinates.latitude);
-        float minLon = nodes.Min(node => node.coordinates.longitude);
-        float maxLat = nodes.Max(node => node.coordinates.latitude);
-        float maxLon = nodes.Max(node => node.coordinates.longitude);
 
+    public static void DrawLoadedNodes(Dictionary<OsmNode, double> gScoreDict, List<Coordinates> pathCoordinates, string workingDir)
+    {
+        float minLat = gScoreDict.Min(kv => kv.Key.coordinates.latitude);
+        float minLon = gScoreDict.Min(kv => kv.Key.coordinates.longitude);
+        float maxLat = gScoreDict.Max(kv => kv.Key.coordinates.latitude);
+        float maxLon = gScoreDict.Max(kv => kv.Key.coordinates.longitude);
+
+        double minWeight = gScoreDict.Min(kv => kv.Value);
+        double maxWeight = gScoreDict.Max(kv => kv.Value);
+        
         float latDiff = maxLat - minLat;
         float lonDiff = maxLon - minLon;
 
@@ -26,21 +29,51 @@ public class Renderer
         int pixelsY = (int)(latDiff * scaleFactor);
 
         Bitmap ret = new Bitmap(pixelsX, pixelsY, PixelFormat.Format32bppRgb);
-
         Graphics g = Graphics.FromImage(ret);
-        Pen p = new Pen(Color.Black, 2);
         g.Clear(Color.White);
 
-        for (int i = 0; i < nodes.Count - 1; i++)
+        Color start = Color.FromArgb(0, 0, 255);
+        Color center = Color.FromArgb(255, 255, 0);
+        Color end = Color.FromArgb(255, 0, 0);
+
+        foreach (KeyValuePair<OsmNode, double> kv in gScoreDict)
         {
-            Coordinates c1 = nodes[i].coordinates;
+            double percentage = kv.Value / maxWeight;
-            Coordinates c2 = nodes[i+1].coordinates;
+            Brush b = new SolidBrush(GradientPick(percentage, start, center, end));
+            float x = (kv.Key.coordinates.longitude - minLon) * scaleFactor;
+            float y = (maxLat - kv.Key.coordinates.latitude) * scaleFactor;
+            g.FillEllipse(b, x, y, 4, 4);
+        }
+        
+        Pen p = new Pen(Color.Red, 2);
+
+        for (int i = 0; i < pathCoordinates.Count - 1; i++)
+        {
+            Coordinates c1 = pathCoordinates[i];
+            Coordinates c2 = pathCoordinates[i+1];
             Point p1 = new(Convert.ToInt32((c1.longitude - minLon) * scaleFactor), Convert.ToInt32((maxLat - c1.latitude) * scaleFactor));
             Point p2 = new(Convert.ToInt32((c2.longitude - minLon) * scaleFactor), Convert.ToInt32((maxLat - c2.latitude) * scaleFactor));
             g.DrawLine(p, p1, p2);
         }
         
-        ret.Save(@"D:\render.png", ImageFormat.Bmp);
+        ret.Save(Path.Join(Directory.GetParent(workingDir)!.FullName, "routing.png"), ImageFormat.Bmp);
-        return ret;
+    }
+    
+    /*
+     * https://stackoverflow.com/questions/55601338/get-a-color-value-within-a-gradient-based-on-a-value
+     */
+    private static int LinearInterp(int start, int end, double percentage) => start + (int)Math.Round(percentage * (end - start));
+    private static Color ColorInterp(Color start, Color end, double percentage) =>
+        Color.FromArgb(LinearInterp(start.A, end.A, percentage),
+            LinearInterp(start.R, end.R, percentage),
+            LinearInterp(start.G, end.G, percentage),
+            LinearInterp(start.B, end.B, percentage));
+    private static Color GradientPick(double percentage, Color Start, Color Center, Color End) {
+        if (percentage < 0.5)
+            return ColorInterp(Start, Center, percentage / 0.5);
+        else if (percentage == 0.5)
+            return Center;
+        else
+            return ColorInterp(Center, End, (percentage - 0.5)/0.5);
     }
 }

Server/Server.cs

@@ -22,6 +22,5 @@ public class Server
         List<PathNode> result = Pathfinder.AStar("D:/stuttgart-regbez-latest", start,
             finish, Tag.SpeedType.car, 20, 2,
             0);
-        RenderPath.Renderer.DrawFromPath(result);
     }
 }