refactored Triangle

src/org/poly2tri/Poly2Tri.scala

@@ -58,7 +58,7 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
   var segments: ArrayBuffer[Segment] = null
   
   val earClip = new EarClip
-  var earClipResults: Array[Triangle] = null
+  var earClipResults: Array[poly2tri.earClip.Triangle] = null
   
   var polyX: ArrayBuffer[Float] = null
   var polyY: ArrayBuffer[Float] = null
@@ -376,9 +376,9 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
       
     	// Earclip
 	    
-	    earClipResults = new Array[Triangle](maxTriangles)
+	    earClipResults = new Array[poly2tri.earClip.Triangle](maxTriangles)
      
-	    for(i <- 0 until earClipResults.size) earClipResults(i) = new Triangle
+	    for(i <- 0 until earClipResults.size) earClipResults(i) = new poly2tri.earClip.Triangle
 	    val xVerts = polyX.toArray.reverse
 	    val yVerts = polyY.toArray.reverse
 	   
@@ -397,8 +397,8 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
     val polyX = Array(400f, 500f, 520f, 460f, 580f, 480f, 360f, 360f, 300f, 200f, 120f, 200f, 340f, 208f, 180f, 300f)
     val polyY = Array(472f, 392f, 272f, 232f, 212f, 152f, 172f, 52f, 112f, 32f, 92f, 72f, 272f, 212f, 352f, 312f)
     
-    val earClipResults = new Array[Triangle](14)
+    val earClipResults = new Array[poly2tri.earClip.Triangle](14)
-    for(i <- 0 until earClipResults.size) earClipResults(i) = new Triangle
+    for(i <- 0 until earClipResults.size) earClipResults(i) = new poly2tri.earClip.Triangle
     val t1 = System.nanoTime
     earClip.triangulatePolygon(polyX, polyY, polyX.size, earClipResults)
     val t2 = System.nanoTime
@@ -410,8 +410,8 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
     val polyX = Array(200f, 300f, 400f, 500f, 600f, 600f, 500f, 400f, 300f, 200f, 110f, 110f)
     val polyY = Array(110f, 200f, 110f, 200f, 110f, 200f, 300f, 200f, 300f, 200f, 300f, 200f)
     
-    val earClipResults = new Array[Triangle](14)
+    val earClipResults = new Array[poly2tri.earClip.Triangle](14)
-    for(i <- 0 until earClipResults.size) earClipResults(i) = new Triangle
+    for(i <- 0 until earClipResults.size) earClipResults(i) = new poly2tri.earClip.Triangle
     val t1 = System.nanoTime
     earClip.triangulatePolygon(polyX, polyY, polyX.size, earClipResults)
     val t2 = System.nanoTime
@@ -434,8 +434,8 @@ class Poly2TriDemo extends BasicGame("Poly2Tri") {
     val polyX = Array(350f, 379f, 469f, 397f, 423f, 350f, 277f, 303f, 231f, 321f)
     val polyY = Array(75f, 161f, 161f, 215f, 301f, 250f, 301f,215f, 161f, 161f)
     
-    val earClipResults = new Array[Triangle](14)
+    val earClipResults = new Array[poly2tri.earClip.Triangle](14)
-    for(i <- 0 until earClipResults.size) earClipResults(i) = new Triangle
+    for(i <- 0 until earClipResults.size) earClipResults(i) = new poly2tri.earClip.Triangle
     val t1 = System.nanoTime
     earClip.triangulatePolygon(polyX, polyY, polyX.size, earClipResults)
     val t2 = System.nanoTime

src/org/poly2tri/cdt/CDT.scala

@@ -32,7 +32,7 @@ package org.poly2tri.cdt
 
 import scala.collection.mutable.ArrayBuffer
 
-import shapes.{Segment, Point}
+import shapes.{Segment, Point, Triangle}
 import utils.Util
 
 /**
@@ -42,10 +42,15 @@ import utils.Util
  */
 class CDT(segments: ArrayBuffer[Segment]) {
 
+  // The initial triangle
+  var initialTriangle: Triangle = null
   // The point list
   val points = init
   // The triangle mesh
-  val mesh = new Mesh
+  val mesh = new Mesh(initialTriangle)
+  
+  // Used to compute inital triangle
+  private val ALPHA = 0.3f
   
   // Sweep points; build mesh
   sweep
@@ -55,8 +60,8 @@ class CDT(segments: ArrayBuffer[Segment]) {
   // Initialize and sort point list
   private def init: List[Point] = {
     
-    var xmax, xmin = 0f
+    var xmax, xmin = segments(0).p.x
-    var ymax, ymin = 0f
+    var ymax, ymin = segments(0).p.y
     val pts = new ArrayBuffer[Point]
     
     for(i <- 0 until segments.size) { 
@@ -74,18 +79,28 @@ class CDT(segments: ArrayBuffer[Segment]) {
       if(p.y < ymin) ymin = p.x
       if(q.y < ymin) ymin = q.x
       
-      
       pts += shearTransform(p)
       pts += shearTransform(q)
     }
     
+    var points: List[Point] = null
+    
     if(pts.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.
-     Util.insertSort((p1: Point, p2: Point) => p1 > p2)(pts).toList
+     points = Util.insertSort((p1: Point, p2: Point) => p1 > p2)(pts).toList
     else
      // Merge sort: O(n log n)
-     Util.msort((p1: Point, p2: Point) => p1 > p2)(pts.toList)
+     points = Util.msort((p1: Point, p2: Point) => p1 > p2)(pts.toList)
+     
+    val deltaX = ALPHA * (xmax - xmin)
+    val deltaY = ALPHA * (ymax - ymin)
+    
+    val p1 = Point(xmin - deltaX, ymin - deltaY)
+    val p2 = Point(xmax - deltaX, ymin - deltaY)
+    
+    initialTriangle = new Triangle(Array(p2, points(0), p1), null)
+    points
   }
  
   // Implement sweep-line paradigm

src/org/poly2tri/cdt/Mesh.scala

@@ -34,8 +34,8 @@ import scala.collection.mutable.HashSet
 
 import shapes.Point
 
-class Mesh {
+class Mesh(initialTriangle: Triangle) {
 
-  val map = HashSet.empty[Triangle]
+  val map = HashSet(initialTriangle)
   
 }

src/org/poly2tri/cdt/Triangle.scala

@@ -1,40 +0,0 @@
-/* Poly2Tri
- * Copyright (c) 2009, Mason Green
- * http://code.google.com/p/poly2tri/
- *
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- *
- * * Redistributions of source code must retain the above copyright notice,
- *   this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright notice,
- *   this list of conditions and the following disclaimer in the documentation
- *   and/or other materials provided with the distribution.
- * * Neither the name of Poly2Tri nor the names of its contributors may be
- *   used to endorse or promote products derived from this software without specific
- *   prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-package org.poly2tri.cdt
-
-import shapes.Point
-
-// Triangle-based data structures have better performance than quad-edge structures
-// See: Shewchuk, "Triangle: Engineering a 2D Quality Mesh Generator and Delaunay Triangulator"
-//      "Triangulations in CGAL"
-class Triangle(points: Array[Point], neighbors: Array[Triangle]) {
-
-}

src/org/poly2tri/earClip/EarClip.scala

@@ -25,7 +25,7 @@
  */
 package org.poly2tri.earClip
 
-import shapes.{Point, Triangle}
+import shapes.Point
 
 class EarClip {
 
@@ -313,3 +313,56 @@ class Poly(var x: Array[Float], var y: Array[Float], var nVertices: Int) {
 		areaIsSet = false
 	}
 }
+
+class Triangle(var x1: Float, var y1: Float, var x2: Float, var y2: Float, var x3: Float, var y3: Float) {
+    
+	def this() = this(0,0,0,0,0,0)
+ 
+    val x = new Array[Float](3)
+    val y = new Array[Float](3)
+    
+    // Automatically fixes orientation to ccw
+
+	  val dx1 = x2-x1
+	  val dx2 = x3-x1
+	  val dy1 = y2-y1
+	  val dy2 = y3-y1
+	  val cross = dx1*dy2-dx2*dy1
+	  val ccw = (cross>0)
+	  if (ccw){
+	    x(0) = x1; x(1) = x2; x(2) = x3;
+	    y(0) = y1; y(1) = y2; y(2) = y3;
+	  } else{
+	    x(0) = x1; x(1) = x3; x(2) = x2;
+	    y(0) = y1; y(1) = y3; y(2) = y2;
+	  }
+
+    def set(t: Triangle) {
+    	x(0) = t.x(0)
+    	x(1) = t.x(1)
+    	x(2) = t.x(2)
+    	y(0) = t.y(0)
+    	y(1) = t.y(1)
+    	y(2) = t.y(2)
+    }
+
+    
+    def containsPoint(_x: Float, _y: Float): Boolean = {
+      
+      val vx2 = _x-x(0); val vy2 = _y-y(0);
+      val vx1 = x(1)-x(0); val vy1 = y(1)-y(0);
+      val vx0 = x(2)-x(0); val vy0 = y(2)-y(0);
+      
+      val dot00 = vx0*vx0+vy0*vy0;
+      val dot01 = vx0*vx1+vy0*vy1;
+      val dot02 = vx0*vx2+vy0*vy2;
+      val dot11 = vx1*vx1+vy1*vy1;
+      val dot12 = vx1*vx2+vy1*vy2;
+      val invDenom = 1.0f / (dot00*dot11 - dot01*dot01);
+      val u = (dot11*dot02 - dot01*dot12)*invDenom;
+      val v = (dot00*dot12 - dot01*dot02)*invDenom;
+      
+      return ((u>=0)&&(v>=0)&&(u+v<=1));    
+    }
+    
+ }

src/org/poly2tri/shapes/Triangle.scala

@@ -1,54 +1,43 @@
+/* Poly2Tri
+ * Copyright (c) 2009, Mason Green
+ * http://code.google.com/p/poly2tri/
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ * * Neither the name of Poly2Tri nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without specific
+ *   prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
 package org.poly2tri.shapes
 
-class Triangle(var x1: Float, var y1: Float, var x2: Float, var y2: Float, var x3: Float, var y3: Float) {
+import shapes.Point
 
-	def this() = this(0,0,0,0,0,0)
+// 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"
+class Triangle(points: Array[Point], neighbors: Array[Triangle]) {
 
-    val x = new Array[Float](3)
+  // Flags to determine if an edge is the final Delauney edge
-    val y = new Array[Float](3)
+  val edges = new Array[Boolean](3)
-    
-    // Automatically fixes orientation to ccw
-
-	  val dx1 = x2-x1
-	  val dx2 = x3-x1
-	  val dy1 = y2-y1
-	  val dy2 = y3-y1
-	  val cross = dx1*dy2-dx2*dy1
-	  val ccw = (cross>0)
-	  if (ccw){
-	    x(0) = x1; x(1) = x2; x(2) = x3;
-	    y(0) = y1; y(1) = y2; y(2) = y3;
-	  } else{
-	    x(0) = x1; x(1) = x3; x(2) = x2;
-	    y(0) = y1; y(1) = y3; y(2) = y2;
-	  }
-
-    def set(t: Triangle) {
-    	x(0) = t.x(0)
-    	x(1) = t.x(1)
-    	x(2) = t.x(2)
-    	y(0) = t.y(0)
-    	y(1) = t.y(1)
-    	y(2) = t.y(2)
-    }
-
-    
-    def containsPoint(_x: Float, _y: Float): Boolean = {
-      
-      val vx2 = _x-x(0); val vy2 = _y-y(0);
-      val vx1 = x(1)-x(0); val vy1 = y(1)-y(0);
-      val vx0 = x(2)-x(0); val vy0 = y(2)-y(0);
-      
-      val dot00 = vx0*vx0+vy0*vy0;
-      val dot01 = vx0*vx1+vy0*vy1;
-      val dot02 = vx0*vx2+vy0*vy2;
-      val dot11 = vx1*vx1+vy1*vy1;
-      val dot12 = vx1*vx2+vy1*vy2;
-      val invDenom = 1.0f / (dot00*dot11 - dot01*dot01);
-      val u = (dot11*dot02 - dot01*dot12)*invDenom;
-      val v = (dot00*dot12 - dot01*dot02)*invDenom;
-      
-      return ((u>=0)&&(v>=0)&&(u+v<=1));    
-    }
   
 }