optimizations

src/org/poly2tri/MonoToneMountain.scala

@@ -38,15 +38,15 @@ class MonotoneMountain {
 	var tail, head: Point = null
 	var size = 0
 
-	val convexPoints = new ArrayBuffer[Point]
+	private val convexPoints = new ArrayBuffer[Point]
     // Monotone mountain points
 	val monoPoly = new ArrayBuffer[Point]
     // Triangles that constitute the mountain
 	val triangles = new ArrayBuffer[Array[Point]]
 	// Used to track which side of the line we are on                                
-	var positive = false
+	private var positive = false
 	// Almost Pi!
-	val PI_SLOP = 3.1
+	private val PI_SLOP = 3.1
  
 	// Append a point to the list
 	def +=(point: Point) {
@@ -123,7 +123,7 @@ class MonotoneMountain {
    
   }
  
-	def valid(p: Point) = (p != head && p != tail && convex(p))
+	private def valid(p: Point) = (p != head && p != tail && convex(p))
 	  
 	// Create the monotone polygon 
 	private def genMonoPoly { 
@@ -134,13 +134,13 @@ class MonotoneMountain {
 	  }
 	}
  
-	def angle(p: Point) = {
+	private def angle(p: Point) = {
 	  val a = (p.next - p)
 	  val b = (p.prev - p)
 	  Math.atan2(a cross b, a dot b)
 	}
  
-	def angleSign = {
+	private def angleSign = {
 	  val a = (head.next - head)
 	  val b = (tail - head)
 	  (Math.atan2(a cross b, a dot b) >= 0)
@@ -149,7 +149,7 @@ class MonotoneMountain {
 	// Determines if the inslide angle is convex or reflex
 	private def convex(p: Point) = {
 	  if(positive != (angle(p) >= 0)) false
-    else true
+      else true
   }
 
 }

src/org/poly2tri/Segment.scala

@@ -37,14 +37,9 @@ class Segment(var p: Point, var q: Point) {
 
   // Pointers used for building trapezoidal map
   var above, below: Trapezoid = null
-  
-  // This can be adjusted accordingly
-  val MAX_MPOINTS = 20
   // Montone mountain points
-  val mPoints = new Array[Point](MAX_MPOINTS)
+  val mPoints = new ArrayBuffer[Point]
-  // mPoints index counter
+
-  var np = 0
-  
   // Equation of a line: y = m*x + b
   // Slope of the line (m)
   val slope = (q.y - p.y)/(q.x - p.x)
@@ -52,8 +47,8 @@ class Segment(var p: Point, var q: Point) {
   val b = p.y - (p.x * slope)
   
   // Determines if this segment lies above the given point
-  @inline def > (point: Point) = (point.y < Math.round(slope * point.x + b))
+  def > (point: Point) = (point.y < Math.round(slope * point.x + b))
   // Determines if this segment lies below the given point
-  @inline def < (point: Point) = (point.y > Math.round(slope * point.x + b))
+  def < (point: Point) = (point.y > Math.round(slope * point.x + b))
 
 }

src/org/poly2tri/Sink.scala

@@ -34,7 +34,6 @@ object Sink {
   
   def init(trapezoid: Trapezoid) = {
     if(trapezoid.sink != null) 
-      // What about adding to the parent list?
       trapezoid.sink
     else 
       new Sink(trapezoid)

src/org/poly2tri/Trapezoid.scala

@@ -41,14 +41,27 @@ class Trapezoid(val leftPoint: Point, var rightPoint: Point, val top: Segment, v
   var upperRight: Trapezoid = null
   var lowerRight: Trapezoid = null
   
-  def update(ul: Trapezoid, ll: Trapezoid, ur: Trapezoid, lr: Trapezoid) {
+  // Update neighbors to the left
+  def updateLeft(ul: Trapezoid, ll: Trapezoid) {
+    upperLeft = ul; if(ul != null) ul.upperRight = this
+    lowerLeft = ll; if(ll != null) ll.lowerRight = this  
+  }
+  
+  // Update neighbors to the right
+  def updateRight(ur: Trapezoid, lr: Trapezoid) {
+    upperRight = ur; if(ur != null) ur.upperLeft = this
+    lowerRight = lr; if(lr != null) lr.lowerLeft = this    
+  }
+  
+  // Update neighbors on both sides
+  def updateLeftRight(ul: Trapezoid, ll: Trapezoid, ur: Trapezoid, lr: Trapezoid) {
     upperLeft = ul; if(ul != null) ul.upperRight = this
     lowerLeft = ll; if(ll != null) ll.lowerRight = this
     upperRight = ur; if(ur != null) ur.upperLeft = this
     lowerRight = lr; if(lr != null) lr.lowerLeft = this    
   }
   
-  // Recursively trim neightbors
+  // Recursively trim outside neighbors
   def trimNeighbors {
     if(inside) {
       inside = false
@@ -80,10 +93,10 @@ class Trapezoid(val leftPoint: Point, var rightPoint: Point, val top: Segment, v
   
   // Add points to monotone mountain
   def addPoints {
-    if(leftPoint != bottom.p) {bottom.mPoints(bottom.np) = leftPoint.clone; bottom.np += 1}
+    if(leftPoint != bottom.p) {bottom.mPoints += leftPoint.clone}
-    if(rightPoint != bottom.q) {bottom.mPoints(bottom.np) = rightPoint.clone; bottom.np += 1}
+    if(rightPoint != bottom.q) {bottom.mPoints += rightPoint.clone}
-    if(leftPoint != top.p) {top.mPoints(top.np) = leftPoint.clone; top.np += 1}
+    if(leftPoint != top.p) {top.mPoints += leftPoint.clone}
-    if(rightPoint != top.q) {top.mPoints(top.np) = rightPoint.clone; top.np += 1}
+    if(rightPoint != top.q) {top.mPoints += rightPoint.clone}
   }
   
   def debugData {

src/org/poly2tri/TrapezoidalMap.scala

@@ -46,19 +46,7 @@ class TrapezoidalMap {
   // Top segment that spans multiple trapezoids
   private var tCross: Segment = null
   
-  // Add a trapezoid to the map
+  def clear {
-  def add(t: Trapezoid) {
-    assert(t != null, "Bad value")
-    map += t
-  }
-  
-  // Remove a trapezoid from the map
-  def remove(t: Trapezoid) {
-    assert(t != null, "Bad value")
-    map -=t
-  }
-  
-  def reset {
     bCross = null
     tCross = null
   }
@@ -73,10 +61,10 @@ class TrapezoidalMap {
     trapezoids(2) = new Trapezoid(s.p, s.q, s, t.bottom)
     trapezoids(3) = new Trapezoid(s.q, t.rightPoint, t.top, t.bottom)
     
-    trapezoids(0).update(t.upperLeft, t.lowerLeft, trapezoids(1), trapezoids(2))
+    trapezoids(0).updateLeft(t.upperLeft, t.lowerLeft)
-    trapezoids(1).update(trapezoids(0), null, trapezoids(3), null)
+    trapezoids(1).updateLeftRight(trapezoids(0), null, trapezoids(3), null)
-    trapezoids(2).update(null, trapezoids(0), null, trapezoids(3))
+    trapezoids(2).updateLeftRight(null, trapezoids(0), null, trapezoids(3))
-    trapezoids(3).update(trapezoids(1), trapezoids(2), t.upperRight, t.lowerRight)
+    trapezoids(3).updateRight(t.upperRight, t.lowerRight)
     
     trapezoids
   }
@@ -92,9 +80,9 @@ class TrapezoidalMap {
     trapezoids(1) = new Trapezoid(s.p, rp, t.top, s)
     trapezoids(2) = new Trapezoid(s.p, rp, s, t.bottom)
    
-    trapezoids(0).update(t.upperLeft, t.lowerLeft, trapezoids(1), trapezoids(2))
+    trapezoids(0).updateLeft(t.upperLeft, t.lowerLeft)
-    trapezoids(1).update(trapezoids(0), null, t.upperRight, null)
+    trapezoids(1).updateLeftRight(trapezoids(0), null, t.upperRight, null)
-    trapezoids(2).update(null, trapezoids(0), null, t.lowerRight)
+    trapezoids(2).updateLeftRight(null, trapezoids(0), null, t.lowerRight)
     
     bCross = t.bottom
     tCross = t.top
@@ -122,7 +110,7 @@ class TrapezoidalMap {
       if(t.upperRight != null) t.upperRight.upperLeft = trapezoids(0)
       trapezoids(0).rightPoint = rp
     } else {
-      trapezoids(0).update(t.upperLeft, s.above, t.upperRight, null)
+      trapezoids(0).updateLeftRight(t.upperLeft, s.above, t.upperRight, null)
     }
     
     if(bottomCross) {
@@ -130,7 +118,7 @@ class TrapezoidalMap {
       if(t.lowerRight != null) t.lowerRight.lowerLeft = trapezoids(1)
       trapezoids(1).rightPoint = rp
     } else {
-      trapezoids(1).update(s.below, t.lowerLeft, null, t.lowerRight)
+      trapezoids(1).updateLeftRight(s.below, t.lowerLeft, null, t.lowerRight)
     }
     
     bCross = t.bottom
@@ -156,20 +144,18 @@ class TrapezoidalMap {
     trapezoids(2) = new Trapezoid(s.q, t.rightPoint, t.top, t.bottom)
     
     if(topCross) {
-      trapezoids(0).upperRight = trapezoids(2)
       trapezoids(0).rightPoint = s.q
     } else {
-      trapezoids(0).update(t.upperLeft, s.above, trapezoids(2), null)
+      trapezoids(0).updateLeft(t.upperLeft, s.above)
     }
     
     if(bottomCross) {
-      trapezoids(1).lowerRight = trapezoids(2)
       trapezoids(1).rightPoint = s.q
     } else {
-      trapezoids(1).update(s.below, t.lowerLeft, null, trapezoids(2))
+      trapezoids(1).updateLeft(s.below, t.lowerLeft)
     }
     
-    trapezoids(2).update(trapezoids(0), trapezoids(1), t.upperRight, t.lowerRight)
+    trapezoids(2).updateLeftRight(trapezoids(0), trapezoids(1), t.upperRight, t.lowerRight)
     
     s.above = trapezoids(0)
     s.below = trapezoids(1)

src/org/poly2tri/Triangulator.scala

@@ -51,20 +51,21 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
   def process {
     
     val t1 = System.nanoTime
-    var i = 0
     
+    var i = 0
     while(i < segmentList.size) {
       
       val s = segmentList(i)
+      
       var traps = queryGraph.followSegment(s)
       
       // Remove trapezoids from trapezoidal Map
       var j = 0
       while(j < traps.size) {
-        trapezoidalMap.remove(traps(j))
+        trapezoidalMap.map -= traps(j)
         j += 1
       }
-      
+     
       j = 0
       while(j < traps.size) {
         val t = traps(j)
@@ -88,17 +89,19 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
           tList = trapezoidalMap.case4(t, s)
           queryGraph.case4(t.sink, s, tList)
         }
+        
         // Add new trapezoids to map
         var k = 0
         while(k < tList.size) {
-          trapezoidalMap.add(tList(k))
+          trapezoidalMap.map += tList(k)
           k += 1
         }
         j += 1
       }
       
-      trapezoidalMap.reset
+      trapezoidalMap.clear
       i += 1
+    
     }
     
     coreTime = System.nanoTime - t1
@@ -117,15 +120,6 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
     // Generate the triangles
     createMountains 
     
-    // Extract all the triangles into a single list
-    for(i <- 0 until xMonoPoly.size) {
-      var j = 0
-      while(j < xMonoPoly(i).triangles.size) {
-    	triangles += xMonoPoly(i).triangles(j)
-        j += 1
-      }
-    }
-    
     //println("# triangles = " + triangles.size)
   }
   
@@ -150,29 +144,47 @@ class Triangulator(segments: ArrayBuffer[Segment]) {
   
   // Build a list of x-monotone mountains
   private def createMountains {
+    
     var i = 0
     while(i < segmentList.size) {
+      
       val s = segmentList(i)
-      if(s.np > 0) {
+      
+      if(s.mPoints.size > 0) {
+        
          val mountain = new MonotoneMountain
          var k: List[Point] = null
-         val tmp = new Array[Point](s.np)
+    
-         for(i <- 0 until s.np) tmp(i) = s.mPoints(i)
+         // Sorting is a perfromance hit. Literature says this can be accomplised in
-         if(s.np < 10) 
+         // linear time, although I don't see a way around using traditional methods
+         // when using a randomized incremental algorithm
+         if(s.mPoints.size < 10) 
            // Insertion sort is one of the fastest algorithms for sorting arrays containing 
            // fewer than ten elements, or for lists that are already mostly sorted.
-           k = Util.insertionSort(tmp.toList, {(x1, x2) => x1 <= x2} )
+           k = Util.insertSort(s.mPoints).toList
          else 
-           k = Util.msort((p1: Point, p2: Point) => p1 < p2)(tmp.toList)
+           k = Util.msort((p1: Point, p2: Point) => p1 < p2)(s.mPoints.toList)
+         
          val points = s.p :: k ::: List(s.q)
+         
          var j = 0
          while(j < points.size) {
            mountain += points(j)
            j += 1
          }
+         
+         // Triangulate monotone mountain
          val t1 = System.nanoTime
          mountain.triangulate
          coreTime += System.nanoTime - t1
+         
+         // Extract the triangles into a single list
+         j = 0
+         while(j < mountain.triangles.size) {
+    	   triangles += mountain.triangles(j)
+           j += 1
+         }
+         
          xMonoPoly += mountain
       }
       i += 1

src/org/poly2tri/Util.scala

@@ -17,29 +17,20 @@ object Util {
       else merge(msort(less)(xs take n), msort(less)(xs drop n))
   }
   
-  def insertionSort(values : List[Point], matcher : (Float, Float) => Boolean) : List[Point] = {
+  def insertSort(list:ArrayBuffer[Point]) = {     
-       def iSort(values : List[Point]) : List[Point] = {
+    var j = 1
-           val result = values match {
+    while(j < list.size){   
-               case List() => List()
+	   val key = list(j)
-               case value :: valuesTail => insert(value, iSort(valuesTail))
+	   var i = j-1
-           }
+	   while(i>=0 && list(i).x > key.x){
-           result
+	     list(i+1) = list(i)
-       }
+	     i=i-1
-       def insert(value : Point, values : List[Point]) : List[Point] = {
+	   }
-           val result = values match {
+	   list(i+1)=key
-               // if list is empty return new list with single element in it
+	   j=j+1
-               case List() => List(value)
+	 }
-               // otherwise insert into list in order, recursively
+	 list
-               case x :: xTail =>
+  }
-                   if (matcher(value.x, x.x)) 
-                       value :: values
-                   else 
-                       x :: insert(value, xTail)
-           }
-           result
-       }
-       iSort(values)
-   }
 }
 
 /** The object <code>Random</code> offers a default implementation

src/org/poly2tri/YNode.scala

@@ -33,20 +33,15 @@ package org.poly2tri
 class YNode(segment: Segment, lChild: Node, rChild: Node) extends Node(lChild, rChild) {
 
   override def locate(s: Segment): Sink = {
-    //println(s.p.y)
-    //println(Math.round(segment.slope * s.p.x + segment.b))
     if (segment > s.p) {
       // Move down the graph
       return right.locate(s)
     } else if (segment < s.p) {
-      //println("*****")
-      //println(s.p.y)
-      //println(Math.round(segment.slope * s.p.x + segment.b))
       // Move up the graph
       return left.locate(s)
     } else {
       // s and segment share the same endpoint, p
-      if (Math.round(s.slope) < Math.round(segment.slope)) {
+      if (s.slope < segment.slope) {
         // Move down the graph
         return right.locate(s)
       } else {