package org.papervision3d.core.math.util
  {
          import org.papervision3d.core.geom.renderables.Triangle3D;
          import org.papervision3d.core.geom.renderables.Vertex3D;
          import org.papervision3d.core.math.Plane3D;
          
          public class @ax-student-ar-org-papervision3d-core-math-util-ClassificationUtil
          {
                  public static const FRONT:uint = 0;
                  public static const BACK:uint = 1;
                  public static const COINCIDING:uint = 2;
                  public static const STRADDLE:uint = 3;
                  
                  public function @ax-student-ar-org-papervision3d-core-math-util-ClassificationUtil()
                  {
                          
                  }
                  
                  public static function classifyPoint( point:Vertex3D, plane:Plane3D, e:Number = 0.01 ):uint
                  {
                          var distance:Number = plane.vertDistance( point );
                          if(distance < -e){
                                  return BACK;
                          }else if(distance > e){
                                  return FRONT;
                          }else{ 
                                  return COINCIDING;
                          }
                  }
                  
                  protected static var point:Vertex3D;
                  public static function classifyPoints( points:Array, plane:Plane3D, e:Number = 0.01 ):uint
                  {
                          var numpos:uint = 0;
                          var numneg:uint = 0;
                          for each(point in points )
                          {
                                  var side:uint = classifyPoint(point, plane, e);
                                  if( side == FRONT ){
                                          numpos++;
                                  }else if( side == BACK ){
                                          numneg++;
                                  }
                          }
                          if( numpos > 0 && numneg == 0 ){
                                  return FRONT;
                          }else if( numpos == 0 && numneg > 0 ){
                                  return BACK;
                          }else if( numpos > 0 && numneg > 0 ){
                                  return STRADDLE;
                          }else{
                                  return COINCIDING;
                          }
                  }
                  
                  public static function classifyTriangle(triangle:Triangle3D, plane:Plane3D, e:Number=0.01 ):uint
                  {                        
                          if(!triangle){
                                  return null;
                          }
                          return classifyPoints(triangle.vertices, plane, e);//[triangle.v0, triangle.v1, triangle.v2], plane, e);
                  }
                  
          }
  }