influence region

src/org/poly2tri/Poly2Tri.scala

@@ -75,7 +75,6 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
   var drawSegs = true
   var hiLighter = 0
   var drawEarClip = false
-  var hertelMehlhorn = false
   var drawCDT = false
   
   val nazcaMonkey = "data/nazca_monkey.dat"
@@ -201,7 +200,6 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
     if(c == '6') selectModel(i18)
     if(c == 's') drawSegs = !drawSegs
     if(c == 'e') {drawEarClip = !drawEarClip; selectModel(currentModel)}
-    if(c == 'h') {hertelMehlhorn = !hertelMehlhorn; selectModel(currentModel)} 
   }
     
   def selectModel(model: String) {
@@ -262,7 +260,6 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
       
 	    // Sediel triangulation
 	    seidel = new Triangulator(segments)
-        seidel.buildTriangles = hertelMehlhorn
         
 	    val t1 = System.nanoTime
 	    seidel.process

src/org/poly2tri/cdt/CDT.scala

@@ -122,13 +122,13 @@ class CDT(val points: List[Point], val segments: List[Segment], iTriangle: Trian
   
   // Implement sweep-line 
   private def sweep {
-    for(i <- 1 until 9 /*points.size*/) {
+    for(i <- 1 until points.size) {
       val point = points(i)
-      println(point)
       // Process Point event
-      val triangle = pointEvent(point)
+      //val triangle = 
+      pointEvent(point)
       // Process edge events
-     point.edges.foreach(e => edgeEvent(e, triangle))
+      //point.edges.foreach(e => edgeEvent(e, triangle))
     }
   }  
   
@@ -164,12 +164,40 @@ class CDT(val points: List[Point], val segments: List[Segment], iTriangle: Trian
   
   // EdgeEvent
   private def edgeEvent(edge: Segment, triangle: Triangle) { 
+    
     // STEP 1: Locate the first intersected triangle
-    val first = triangle.locateFirst(edge)
-    println(first)
-    if(first != null && first != triangle && !first.contains(edge)) 
-      mesh.map -= first
+    val firstTriangle = triangle.locateFirst(edge)
     // STEP 2: Remove intersected triangles
+    if(firstTriangle != null && !firstTriangle.contains(edge)) {
+       // Collect intersected triangles
+       val triangles = new ArrayBuffer[Triangle]
+       triangles += firstTriangle
+       while(!triangles.last.contains(edge.p)) 
+         triangles += triangles.last.findNeighbor(edge.p - edge.q)
+       // Remove from the mesh
+       triangles.foreach(t => mesh.map -= t)
+    } else if(firstTriangle == null) {
+      
+      // Traverse the AFront, and build triangle list
+     
+      var node = aFront.locate(edge.q)
+      
+      if(edge.p.x > edge.q.x) {
+        // Search right
+        while(node.point != edge.p) {
+          // Collect points
+          node = node.next
+        }
+      } else {
+        // Search left
+        while(node.point != edge.p) {
+          // Collect points
+          node = node.prev
+        }
+      }
+      
+    }
+    
     // STEP 3: Triangulate empty areas.
   }
   

src/org/poly2tri/seidel/MonotoneMountain.scala

@@ -35,7 +35,7 @@ import scala.collection.mutable.{ArrayBuffer, Queue}
 import shapes.Point
 
 // Doubly linked list
-class MonotoneMountain(buildTriangles: Boolean) {
+class MonotoneMountain {
 
 	var tail, head: Point = null
 	var size = 0
@@ -108,10 +108,7 @@ class MonotoneMountain(buildTriangles: Boolean) {
         p = p.next
       }
       
-      if(buildTriangles) 
-    	triangulate
-       else
-        hertelMehlhorn
+      triangulate
 
     }
  
@@ -135,30 +132,7 @@ class MonotoneMountain(buildTriangles: Boolean) {
       assert(size <= 3, "Triangulation bug, please report")
    
 	}
- 
-	private def hertelMehlhorn {
-	  
-		while(!convexPoints.isEmpty) {
-	        val ear = convexPoints.remove(0)
-	        val a = ear.prev
-	        val b = ear
-	        val c = ear.next
-	        val triangle = Array(a, b, c)
-	        convexPolies += triangle
-	        // Remove ear, update angles and convex list
-	        remove(ear)
-        }
-  
-		val polygon = new Array[Point](size)
-		
-		var p = head
-		for(i <- 0 until size) {
-		  polygon(i) = p
-          p = p.next
-		}
-        convexPolies += polygon
-	}
- 
+
 	private def valid(p: Point) = (p != head && p != tail && convex(p))
 	  
 	// Create the monotone polygon 

src/org/poly2tri/seidel/Triangulator.scala

@@ -43,9 +43,6 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
   
   // Convex polygon list
   var polygons = new ArrayBuffer[Array[Point]]
-  // Generate triangles vs non-convex polygons 
-  // On by default
-  var buildTriangles = true
   // Order and randomize the segments
   val segmentList = orderSegments
   
@@ -149,7 +146,7 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
       
       if(s.mPoints.size > 0) {
         
-         val mountain = new MonotoneMountain(buildTriangles)
+         val mountain = new MonotoneMountain
          var k: List[Point] = null
     
          // Sorting is a perfromance hit. Literature says this can be accomplised in
@@ -173,20 +170,11 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
          // Triangulate monotone mountain
          mountain process
          
-         if(buildTriangles) {
-	         // Extract the triangles into a single list
-	         j = 0
-	         while(j < mountain.triangles.size) {
-	    	   polygons += mountain.triangles(j)
-	           j += 1
-	         }
-         } else {
-        	 // Extract the convex polygons into a single list
-	         j = 0
-	         while(j < mountain.convexPolies.size) {
-	    	   polygons += mountain.convexPolies(j)
-	           j += 1
-	         }
+         // Extract the triangles into a single list
+         j = 0
+         while(j < mountain.triangles.size) {
+    	   polygons += mountain.triangles(j)
+           j += 1
          }
          
          xMonoPoly += mountain

src/org/poly2tri/shapes/Segment.scala

@@ -53,13 +53,14 @@ class Segment(var p: Point, var q: Point) {
   
   // Update point edge list for CDT
   def updateEdge {
-	if(p.y > q.y) {
+	if(q.y > p.y) {
 	  // For CDT we want q to be the point with > y
-      val tmp = p
-      p = q
-      q = tmp
+     // val tmp = p
+      //p = q
+      //q = tmp
+      q.edges += this
      }
-	q.edges += this
+	
   }
   
 }

src/org/poly2tri/shapes/Triangle.scala

@@ -30,6 +30,8 @@
  */
 package org.poly2tri.shapes
 
+import scala.collection.mutable.ArrayBuffer
+
 // Triangle-based data structures are know to have better performance than quad-edge structures
 // See: J. Shewchuk, "Triangle: Engineering a 2D Quality Mesh Generator and Delaunay Triangulator"
 //      "Triangulations in CGAL"
@@ -65,7 +67,7 @@ class Triangle(val points: Array[Point], val neighbors: Array[Triangle]) {
   }
   
   def contains(p: Point): Boolean = (p == points(0) || p == points(1) || p == points(2))
-  def contains(e: Segment): Boolean = (contains(e.p) || contains(e.q))
+  def contains(e: Segment): Boolean = (contains(e.p) && contains(e.q))
   
   // Fast point in triangle test
   def pointIn(point: Point): Boolean = {
@@ -86,7 +88,7 @@ class Triangle(val points: Array[Point], val neighbors: Array[Triangle]) {
     val p = edge.p
     if(contains(p)) return this
     val q = edge.q
-    val e = q - p
+    val e = p - q
     if(q == points(0)) {
       val sameSign = Math.signum(ik cross e) == Math.signum(ij cross e)
       if(!sameSign) return this
@@ -105,4 +107,15 @@ class Triangle(val points: Array[Point], val neighbors: Array[Triangle]) {
     }
     throw new Exception("location error")
   }
+  
+  def findNeighbor(e: Point): Triangle = {
+    var sameSign = Math.signum(ik cross e) == Math.signum(ij cross e)
+    if(!sameSign) return neighbors(0)
+    sameSign = Math.signum(jk cross e) == Math.signum(ji cross e)
+    if(!sameSign) return neighbors(1)
+    sameSign = Math.signum(kj cross e) == Math.signum(ki cross e)
+    if(!sameSign) return neighbors(2)
+    this
+  }
+  
 }