Make algorithm multithreaded

Vort · Jan 9, 2017 · 0fadaf9 · 0fadaf9
1 parent c78eaa9
commit 0fadaf9
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Showing 5 changed files with 42 additions and 39 deletions.
diff --git a/Color.cs b/Color.cs
@@ -26,6 +26,15 @@ public double DifferenceTo(Color c)
             return rgb1.Compare(rgb2, cie);
         }
 
+        public static Color Lerp(Color c1, Color c2, double x)
+        {
+            double omx = 1 - x;
+            return new Color(
+                (byte)(c1.R * omx + c2.R * x),
+                (byte)(c1.G * omx + c2.G * x),
+                (byte)(c1.B * omx + c2.B * x));
+        }
+
         public byte R;
         public byte G;
         public byte B;

diff --git a/Program.cs b/Program.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Diagnostics;
 using System.Globalization;
 using System.IO;
 using System.Reflection;
@@ -81,14 +82,19 @@ static void Main(string[] args)
                     Config.Write();
                     if (go)
                     {
-                        try
+                        if (!Debugger.IsAttached)
                         {
-                            new Tracer();
-                        }
-                        catch (Exception e)
-                        {
-                            Console.Error.WriteLine(e);
+                            try
+                            {
+                                new Tracer();
+                            }
+                            catch (Exception e)
+                            {
+                                Console.Error.WriteLine(e);
+                            }
                         }
+                        else
+                            new Tracer();
                     }
                     else
                         Console.WriteLine("<osm version='0.6'></osm>");

diff --git a/SimpleBitmap.cs b/SimpleBitmap.cs
@@ -5,23 +5,6 @@
 
 namespace RiverTrace
 {
-    class ColorLerp
-    {
-        public static Color Lerp(Color c1, Color c2, double minV, double maxV, double V)
-        {
-            return Lerp(c1, c2, (V - minV) / (maxV - minV));
-        }
-
-        public static Color Lerp(Color c1, Color c2, double x)
-        {
-            double omx = 1 - x;
-            return new Color(
-                (byte)(c1.R * omx + c2.R * x),
-                (byte)(c1.G * omx + c2.G * x),
-                (byte)(c1.B * omx + c2.B * x));
-        }
-    }
-
     class SimpleBitmap
     {
         public byte[] Data;

diff --git a/TileMap.cs b/TileMap.cs
@@ -35,9 +35,9 @@ public Color GetPixel(double x, double y)
             Color c21 = GetPixel(flxi, flyi - 1);
             Color c22 = GetPixel(flxi, flyi);
 
-            return ColorLerp.Lerp(
-                ColorLerp.Lerp(c11, c21, frx),
-                ColorLerp.Lerp(c12, c22, frx), fry);
+            return Color.Lerp(
+                Color.Lerp(c11, c21, frx),
+                Color.Lerp(c12, c22, frx), fry);
         }
 
         public Color GetPixel(int x, int y)

diff --git a/Tracer.cs b/Tracer.cs
@@ -118,9 +118,9 @@ public Tracer()
                 if (Config.Data.debug)
                     sb = new SimpleBitmap(pixelRange * 2, pixelRange);
                 var angles = new Dictionary<double, double>();
-                for (int i = 0; i < pixelRange; i++)
+                Parallel.For(0, pixelRange, j =>
                 {
-                    for (int j = 0; j < pixelRange; j++)
+                    for (int i = 0; i < pixelRange; i++)
                     {
                         int x = (int)(lastPoint.X + i - scanRadius);
                         int y = (int)(lastPoint.Y + j - scanRadius);
@@ -140,25 +140,29 @@ public Tracer()
 
                         Color c = tileMap.GetPixel(x, y);
                         if (Config.Data.debug)
-                            sb.SetPixel(i, j, c);
+                            sb.SetPixel(i, pixelRange - j - 1, c);
 
                         double invDiff = Math.Max(1.0 -
                             waterColor.DifferenceTo(c) / Config.Data.shoreContrast, 0.0);
 
                         if (Config.Data.debug)
                         {
                             byte diffColor = (byte)Math.Round(invDiff * 255.0);
-                            sb.SetPixel(i + pixelRange, j, new Color(diffColor, diffColor, diffColor));
+                            sb.SetPixel(i + pixelRange, pixelRange - j - 1, new Color(diffColor, diffColor, diffColor));
                         }
 
                         if (invDiff != 0.0)
                         {
-                            if (!angles.ContainsKey(angle))
-                                angles[angle] = 0.0;
-                            angles[angle] += invDiff;
+                            lock (angles)
+                            {
+                                if (!angles.ContainsKey(angle))
+                                    angles[angle] = invDiff;
+                                else
+                                    angles[angle] += invDiff;
+                            }
                         }
                     }
-                }
+                });
 
                 samples.Add(sb);
 
@@ -184,18 +188,19 @@ public Tracer()
             way.Reverse();
             WriteOsm(way);
 
+            for (int i = 0; i < 25; i++)
+                Console.WriteLine();
+            Console.WriteLine("<!--");
+            Console.WriteLine("Elapsed = " + sw.Elapsed.TotalSeconds + " sec");
+            Console.WriteLine("-->");
+
             if (Config.Data.debug)
             {
                 SimpleBitmap sampleChain = new SimpleBitmap(
                     samples[0].Width, samples[0].Height * samples.Count);
                 for (int i = 0; i < samples.Count; i++)
                     samples[i].CopyTo(sampleChain, i * samples[0].Height);
                 sampleChain.WriteTo("sample_chain.png");
-                for (int i = 0; i < 50; i++)
-                    Console.WriteLine();
-                Console.WriteLine("<!--");
-                Console.WriteLine("Elapsed = " + sw.Elapsed.TotalSeconds);
-                Console.WriteLine("-->");
             }
         }
     }