From c678e615a24c0f3553fb2eaf50f6f73151b1d636 Mon Sep 17 00:00:00 2001
From: codeimp <codeimp@e0d998f2-2e9b-42fe-843d-47128df60a06>
Date: Fri, 3 Oct 2008 14:31:25 +0000
Subject: [PATCH] experimental label position calculator

---
 Source/Geometry/SectorTools.cs | 56 +++++++++++++++++++++++++++++++++-
 Source/Map/Sector.cs           | 26 +++++++++++++++-
 2 files changed, 80 insertions(+), 2 deletions(-)

diff --git a/Source/Geometry/SectorTools.cs b/Source/Geometry/SectorTools.cs
index fe00533d..78a054ea 100644
--- a/Source/Geometry/SectorTools.cs
+++ b/Source/Geometry/SectorTools.cs
@@ -50,7 +50,7 @@ namespace CodeImp.DoomBuilder.Geometry
 		#endregion
 		
 		#region ================== Constants
-
+		
 		#endregion
 
 		#region ================== Pathfinding
@@ -579,5 +579,59 @@ namespace CodeImp.DoomBuilder.Geometry
 		}
 		
 		#endregion
+		
+		#region ================== Sector Labels
+		
+		// This finds the ideal label position for a sector
+		public static Vector2D FindLabelPosition(Sector s, float resolution)
+		{
+			Vector2D foundpoint = new Vector2D();
+			float founddist = 0.0f;
+			
+			// Calculate grid numbers
+			RectangleF bbox = s.CreateBBox();
+			int nodesx = (int)(bbox.Width / resolution);
+			int nodesy = (int)(bbox.Height / resolution);
+			
+			// Make list of linedefs
+			List<Linedef> lines = new List<Linedef>(s.Sidedefs.Count);
+			foreach(Sidedef sd in s.Sidedefs) lines.Add(sd.Line);
+			
+			// Scan the polygon
+			for(int x = 0; x < nodesx; x++)
+			{
+				for(int y = 0; y < nodesy; y++)
+				{
+					// Calculate absolute point
+					Vector2D p = new Vector2D(bbox.X + (float)x * resolution,
+											  bbox.Y + (float)y * resolution);
+					
+					// Point inside sector?
+					Linedef ld = MapSet.NearestLinedef(lines, p);
+					Sidedef sd = (ld.SideOfLine(p) < 0) ? ld.Front : ld.Back;
+					if((sd != null) && (sd.Sector == s))
+					{
+						// Go for all linedefs to calculate the smallest distance
+						float mindist = int.MaxValue;
+						foreach(Linedef l in lines)
+						{
+							float dist = l.DistanceToSq(p, true);
+							if(dist < mindist) mindist = dist;
+						}
+						
+						// Better match?
+						if(mindist > founddist)
+						{
+							foundpoint = p;
+							founddist = mindist;
+						}
+					}
+				}
+			}
+			
+			return foundpoint;
+		}
+		
+		#endregion
 	}
 }
diff --git a/Source/Map/Sector.cs b/Source/Map/Sector.cs
index 55bfccbe..f89ef8cb 100644
--- a/Source/Map/Sector.cs
+++ b/Source/Map/Sector.cs
@@ -247,7 +247,31 @@ namespace CodeImp.DoomBuilder.Map
 		#endregion
 
 		#region ================== Methods
-
+		
+		// This creates a bounding box rectangle
+		// This requires the sector polygon to be up-to-date!
+		public RectangleF CreateBBox()
+		{
+			// Setup
+			float left = float.MaxValue;
+			float top = float.MaxValue;
+			float right = float.MinValue;
+			float bottom = float.MinValue;
+			
+			// Go for vertices
+			foreach(FlatVertex v in vertices)
+			{
+				// Update rect
+				if(v.x < left) left = v.x;
+				if(v.y < top) top = v.y;
+				if(v.x > right) right = v.x;
+				if(v.y > bottom) bottom = v.y;
+			}
+			
+			// Return rectangle
+			return new RectangleF(left, top, right - left, bottom - top);
+		}
+		
 		// This joins the sector with another sector
 		// This sector will be disposed
 		public void Join(Sector other)