Integration of Tomas Hrasky's port of basic GLU NURBS functionality

from C++ to Java, plus example applications, done as part of his
Bachelor of Science degree at the University of Hradec Králové,
Faculty of Informatics and Management.

Current state of code is documented in
src/classes/com/sun/opengl/impl/nurbs/README.txt.

Example applications require Java 1.5 and are not currently built by
default. Specify -Djogl.nurbs=1 during jogl-demos build with a 1.5
javac on the PATH to build them. Dependent jars are copied to build
output directory.

Deleted old partially-complete GLU NURBS port.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@1389 232f8b59-042b-4e1e-8c03-345bb8c30851

1 files changed, 0 insertions, 1791 deletions

diff --git a/src/classes/com/sun/opengl/impl/nurbs/internals/Subdivider.java b/src/classes/com/sun/opengl/impl/nurbs/internals/Subdivider.java
deleted file mode 100644
index 85b569e25..000000000
--- a/src/classes/com/sun/opengl/impl/nurbs/internals/Subdivider.java
+++ /dev/null
@@ -1,1791 +0,0 @@
-/*
-** License Applicability. Except to the extent portions of this file are
-** made subject to an alternative license as permitted in the SGI Free
-** Software License B, Version 1.1 (the "License"), the contents of this
-** file are subject only to the provisions of the License. You may not use
-** this file except in compliance with the License. You may obtain a copy
-** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
-** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
-**
-** http://oss.sgi.com/projects/FreeB
-**
-** Note that, as provided in the License, the Software is distributed on an
-** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
-** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
-** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
-** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
-**
-** NOTE:  The Original Code (as defined below) has been licensed to Sun
-** Microsystems, Inc. ("Sun") under the SGI Free Software License B
-** (Version 1.1), shown above ("SGI License").   Pursuant to Section
-** 3.2(3) of the SGI License, Sun is distributing the Covered Code to
-** you under an alternative license ("Alternative License").  This
-** Alternative License includes all of the provisions of the SGI License
-** except that Section 2.2 and 11 are omitted.  Any differences between
-** the Alternative License and the SGI License are offered solely by Sun
-** and not by SGI.
-**
-** Original Code. The Original Code is: OpenGL Sample Implementation,
-** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
-** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
-** Copyright in any portions created by third parties is as indicated
-** elsewhere herein. All Rights Reserved.
-**
-** Additional Notice Provisions: The application programming interfaces
-** established by SGI in conjunction with the Original Code are The
-** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
-** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
-** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
-** Window System(R) (Version 1.3), released October 19, 1998. This software
-** was created using the OpenGL(R) version 1.2.1 Sample Implementation
-** published by SGI, but has not been independently verified as being
-** compliant with the OpenGL(R) version 1.2.1 Specification.
-*/
-
-public class Subdivider {
-
-  /**
-   * Constructs a subdivider.
-   */
-  public Subdivider(RenderHints hints, Backend b) {
-    renderhints = hints;
-    arctessellator = new ArcTesselator();
-    backend = b;
-    slicer = new Slicer(b);
-  }
-
-  /**
-   * Resets all state after possible error condition.
-   */
-  public void clear() {
-    // FIXME: looks like nothing to do given that we have no object pools
-  }
-  public void beginTrims() {}
-  public void beginLoop() {
-    pjarc = 0;
-  }
-
-  /**
-   * Adds a bezier arc to a trim loop and to a bin.
-   */
-  public void addArc(float[] cpts, Quilt quilt, long _nuid) {
-    BezierArc bezierArc = new BezierArc();
-    Arc jarc = new Arc(Arc.SIDE_NONE, _nuid);
-    jarc.bezierArc = bezierArc;
-    bezierArc.order = quilt.qspec.order;
-    bezierArc.stride = quilt.qspec.stride;
-    bezierArc.mapdesc = quilt.mapdesc;
-    bezierArc.cpts = cpts;
-    initialbin.addarc( jarc );
-    pjarc = jarc.append( pjarc );
-  }
-
-  /**
-   * Adds a pwl arc to a trim loop and to a bin.
-   */
-  public void addArc(int npts, TrimVertex[] pts, long _nuid) {
-    Arc jarc = new Arc( Arc.SIDE_NONE, _nuid );
-    jarc.pwlArc = new PwlArc( npts, pts );        
-    initialbin.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-  }
-  public void endLoop() {}
-  public void endTrims() {}
-
-  public void beginQuilts() {
-    qlist = null;
-  }
-  public void addQuilt( Quilt quilt ) {
-    quilt.next = qlist;
-    qlist = quilt;
-  }
-  public void endQuilts() {}
-
-  /**
-   * Main curve rendering entry point
-   */
-  public void drawCurves() {
-    float[] from = new float[1];
-    float[] to   = new float[1];
-    Flist bpts = new Flist();
-    qlist.getRange( from, to, bpts );
-
-    renderhints.init( );
-
-    backend.bgncurv();
-    float[] pta = new float[0];
-    float[] ptb = new float[1];
-    for( int i=bpts.start; i<bpts.end-1; i++ ) {
-      pta[0] = bpts.pts[i];
-      ptb[0] = bpts.pts[i+1];
-
-      qlist.downloadAll( pta, ptb, backend );
-
-      Curvelist curvelist = new Curvelist( qlist, pta, ptb );
-      samplingSplit( curvelist, renderhints.maxsubdivisions );
-    }
-    backend.endcurv();
-  }
-  public void drawSurfaces(long nuid) {
-    renderhints.init( );
-
-    if (qlist == null) {
-      //initialbin could be nonempty due to some errors
-      freejarcs(initialbin);
-      return;
-    }
-
-    for( Quilt q = qlist; q != null; q = q.next ) {
-      if( q.isCulled( ) == Defines.CULL_TRIVIAL_REJECT ) {
-        freejarcs( initialbin );
-        return;
-      }
-    }
-
-
-    float[] from = new float[2];
-    float[] to   = new float[2];
-    qlist.getRange( from, to, spbrkpts, tpbrkpts );
-    //perform optimization only when the samplng method is 
-    //DOMAIN_DISTANCE and the display methdo is either 
-    //fill or outline_polygon.
-    bool optimize = (is_domain_distance_sampling && (renderhints.display_method != N_OUTLINE_PATCH));
-
-    if( ! initialbin.isnonempty() ) {
-      if(! optimize )
-        {  
-          makeBorderTrim( from, to );
-        }
-    } else {
-      float[] rate = new float[2];
-      qlist.findRates( spbrkpts, tpbrkpts, rate );
-
-      if( decompose( initialbin, Math.min(rate[0], rate[1]) ) ) 
-        throw new NurbsException( 31 );
-    }
-
-    backend.bgnsurf( renderhints.wiretris, renderhints.wirequads, nuid );
-
-    if( (!initialbin.isnonempty())  && optimize )
-      {
-        int i,j;
-        int num_u_steps;
-        int num_v_steps;
-        for(i=spbrkpts.start; i<spbrkpts.end-1; i++){
-          for(j=tpbrkpts.start; j<tpbrkpts.end-1; j++){
-            float[] pta = new float[2];
-            float[] ptb = new float[2];
-            pta[0] = spbrkpts.pts[i];
-            ptb[0] = spbrkpts.pts[i+1];
-            pta[1] = tpbrkpts.pts[j];
-            ptb[1] = tpbrkpts.pts[j+1];
-            qlist.downloadAll(pta, ptb, backend);
-     
-            num_u_steps = (int) (domain_distance_u_rate * (ptb[0]-pta[0]));
-            num_v_steps = (int) (domain_distance_v_rate * (ptb[1]-pta[1]));
-
-            if(num_u_steps <= 0) num_u_steps = 1;
-            if(num_v_steps <= 0) num_v_steps = 1;
-
-            backend.surfgrid(pta[0], ptb[0], num_u_steps, 
-                             ptb[1], pta[1], num_v_steps);
-            backend.surfmesh(0,0,num_u_steps,num_v_steps);
-
-            continue;
-          }
-        }
-      }
-    else
-      subdivideInS( initialbin );
-
-    backend.endsurf();
-  }
-
-  public int ccwTurn_sl(Arc j1, Arc j2 ) {
-    int v1i             = j1.pwlArc.npts-1;
-    int v1lasti         = 0;
-    int v2i             = 0;
-    int v2lasti         = j2.pwlArc.npts-1;
-    int v1nexti         = v1i-1;
-    int v2nexti         = v2i+1;
-    TrimVertex v1       = j1.pwlArc.pts[v1i];
-    TrimVertex v1last   = j1.pwlArc.pts[v1lasti];
-    TrimVertex v2       = j2.pwlArc.pts[v2i];
-    TrimVertex v2last   = j2.pwlArc.pts[v2lasti];
-    TrimVertex v1next   = j1.pwlArc.pts[v1nexti];
-    TrimVertex v2next   = j2.pwlArc.pts[v2nexti];
-    int sgn;
-
-    assert( v1 != v1last );
-    assert( v2 != v2last );
-
-    // the arcs lie on the line (0 == v1.param[0])
-    if( v1.param[0] == v1next.param[0] && v2.param[0] == v2next.param[0] )
-      return 0;
-
-    if( v2next.param[0] > v2.param[0] || v1next.param[0] > v1.param[0] ) 
-      throw new NurbsException(28);
-
-    if( v1.param[1] < v2.param[1] )
-      return 1;
-    else if( v1.param[1] > v2.param[1] )
-      return 0;
-
-    while( true ) {
-      if( v1next.param[0] > v2next.param[0] ) {
-        assert( v1.param[0] >= v1next.param[0] );
-        assert( v2.param[0] >= v1next.param[0] );
-        switch( bbox( v2next, v2, v1next, 1 ) ) {
-        case -1:
-          return 1;
-        case 0:
-          sgn = ccw( v1next, v2, v2next );
-          if( sgn != -1 ) 
-            return sgn;
-          else {
-            v1i = v1nexti--;
-            v1 = j1.pwlArc.pts[v1i];
-            v1next = j1.pwlArc.pts[v1nexti];
-            if( v1 == v1last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 0;
-        }
-      } else if( v1next.param[0] < v2next.param[0] ) {
-        assert( v1.param[0] >= v2next.param[0] );
-        assert( v2.param[0] >= v2next.param[0] );
-        switch( bbox( v1next, v1, v2next, 1 ) ) {
-        case -1:
-          return 0;
-        case 0:
-          sgn = ccw( v1next, v1, v2next );
-          if( sgn != -1 ) 
-            return sgn;
-          else {
-            v2i = v2nexti++;
-            v2 = j2.pwlArc.pts[v2i];
-            v2next = j2.pwlArc.pts[v2nexti];
-            if( v2 == v2last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 1;
-        }
-      } else {
-        if( v1next.param[1] < v2next.param[1] )
-          return 1;
-        else if( v1next.param[1] > v2next.param[1] )
-          return 0;
-        else {
-          v2i = v2nexti++;
-          v2 = j2.pwlArc.pts[v2i];
-          v2next = j2.pwlArc.pts[v2nexti];
-          if( v2 == v2last ) {
-            return 0; // ill-conditioned, guess answer
-          }
-        }
-      }
-    }
-  }
-
-  public int ccwTurn_sr(Arc j1, Arc j2 ) {
-    // dir = 1
-    int v1i             = j1.pwlArc.npts-1;
-    int v1lasti         = 0;
-    int v2i             = 0;
-    int v2lasti         = j2.pwlArc.npts-1;
-    int v1nexti         = v1i-1;
-    int v2nexti         = v2i+1;
-    TrimVertex v1       = j1.pwlArc.pts[v1i];
-    TrimVertex v1last   = j1.pwlArc.pts[v1lasti];
-    TrimVertex v2       = j2.pwlArc.pts[v2i];
-    TrimVertex v2last   = j2.pwlArc.pts[v2lasti];
-    TrimVertex v1next   = j1.pwlArc.pts[v1nexti];
-    TrimVertex v2next   = j2.pwlArc.pts[v2nexti];
-    int sgn;
-
-    assert( v1 != v1last );
-    assert( v2 != v2last );
-
-    // the arcs lie on the line (0 == v1.param[0])
-    if( v1.param[0] == v1next.param[0] && v2.param[0] == v2next.param[0] )
-      return 0;
-
-    if( v2next.param[0] < v2.param[0] || v1next.param[0] < v1.param[0] )
-      throw new NurbsException(28);
-
-    if( v1.param[1] < v2.param[1] )
-      return 0;
-    else if( v1.param[1] > v2.param[1] )
-      return 1;
-
-    while( true ) {
-      if( v1next.param[0] < v2next.param[0] ) {
-        assert( v1.param[0] <= v1next.param[0] );
-        assert( v2.param[0] <= v1next.param[0] );
-        switch( bbox( v2, v2next, v1next, 1 ) ) {
-        case -1:
-          return 0;
-        case 0:
-          sgn = ccw( v1next, v2, v2next );
-          if( sgn != -1 ) {
-            return sgn;
-          } else {
-            v1i = v1nexti--;
-            v1 = j1.pwlArc.pts[v1i];
-            v1next = j1.pwlArc.pts[v1nexti];
-            if( v1 == v1last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 1;
-        }
-      } else if( v1next.param[0] > v2next.param[0] ) {
-        assert( v1.param[0] <= v2next.param[0] );
-        assert( v2.param[0] <= v2next.param[0] );
-        switch( bbox( v1, v1next, v2next, 1 ) ) {
-        case -1:
-          return 1;
-        case 0:
-          sgn = ccw( v1next, v1, v2next );
-          if( sgn != -1 ) { 
-            return sgn;
-          } else {
-            v2i = v2nexti++;
-            v2 = j2.pwlArc.pts[v2i];
-            v2next = j2.pwlArc.pts[v2nexti];
-            if( v2 == v2last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 0;
-        }
-      } else {
-        if( v1next.param[1] < v2next.param[1] )
-          return 0;
-        else if( v1next.param[1] > v2next.param[1] )
-          return 1;
-        else {
-          v2i = v2nexti++;
-          v2 = j2.pwlArc.pts[v2i];
-          v2next = j2.pwlArc.pts[v2nexti];
-          if( v2 == v2last ) {
-            return 0; // ill-conditioned, guess answer
-          }
-        }
-      }
-    }
-  }
-
-  public int ccwTurn_tl(Arc j1, Arc j2 ) {
-    int v1i             = j1.pwlArc.npts-1;
-    int v1lasti         = 0;
-    int v2i             = 0;
-    int v2lasti         = j2.pwlArc.npts-1;
-    int v1nexti         = v1i-1;
-    int v2nexti         = v2i+1;
-    TrimVertex v1       = j1.pwlArc.pts[v1i];
-    TrimVertex v1last   = j1.pwlArc.pts[v1lasti];
-    TrimVertex v2       = j2.pwlArc.pts[v2i];
-    TrimVertex v2last   = j2.pwlArc.pts[v2lasti];
-    TrimVertex v1next   = j1.pwlArc.pts[v1nexti];
-    TrimVertex v2next   = j2.pwlArc.pts[v2nexti];
-    int sgn;
-
-    assert( v1 != v1last );
-    assert( v2 != v2last );
-
-    // the arcs lie on the line (1 == v1.param[1])
-    if( v1.param[1] == v1next.param[1] && v2.param[1] == v2next.param[1] )
-      return 0;
-
-    if( v2next.param[1] > v2.param[1] || v1next.param[1] > v1.param[1] ) 
-      throw new NurbsException(28 );
-
-    if( v1.param[0] < v2.param[0] )
-      return 0;
-    else if( v1.param[0] > v2.param[0] )
-      return 1;
-
-    while( true ) {
-      if( v1next.param[1] > v2next.param[1] ) {
-        assert( v1.param[1] >= v1next.param[1] );
-        assert( v2.param[1] >= v1next.param[1] );
-        switch( bbox( v2next, v2, v1next, 0 ) ) {
-        case -1:
-          return 0;
-        case 0:
-          sgn = ccw( v1next, v2, v2next );
-          if( sgn != -1 ) 
-            return sgn;
-          else {
-            v1i = v1nexti--;
-            v1 = j1.pwlArc.pts[v1i];
-            v1next = j1.pwlArc.pts[v1nexti];
-            if( v1 == v1last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 1;
-        }
-      } else if( v1next.param[1] < v2next.param[1] ) {
-        switch( bbox( v1next, v1, v2next, 0 ) ) {
-        case -1:
-          return 1;
-        case 0:
-          sgn = ccw( v1next, v1, v2next );
-          if( sgn != -1 ) 
-            return sgn;
-          else {
-            v2i = v2nexti++;
-            v2 = j2.pwlArc.pts[v2i];
-            v2next = j2.pwlArc.pts[v2nexti];
-            if( v2 == v2last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 0;
-        }
-      } else {
-        if( v1next.param[0] < v2next.param[0] )
-          return 0;
-        else if( v1next.param[0] > v2next.param[0] )
-          return 1;
-        else {
-          v2i = v2nexti++;
-          v2 = j2.pwlArc.pts[v2i];
-          v2next = j2.pwlArc.pts[v2nexti];
-          if( v2 == v2last ) {
-            return 0; // ill-conditioned, guess answer
-          }
-        }
-      }
-    }
-  }
-
-  public int ccwTurn_tr(Arc j1, Arc j2) {
-    int v1i             = j1.pwlArc.npts-1;
-    int v1lasti         = 0;
-    int v2i             = 0;
-    int v2lasti         = j2.pwlArc.npts-1;
-    int v1nexti         = v1i-1;
-    int v2nexti         = v2i+1;
-    TrimVertex v1       = j1.pwlArc.pts[v1i];
-    TrimVertex v1last   = j1.pwlArc.pts[v1lasti];
-    TrimVertex v2       = j2.pwlArc.pts[v2i];
-    TrimVertex v2last   = j2.pwlArc.pts[v2lasti];
-    TrimVertex v1next   = j1.pwlArc.pts[v1nexti];
-    TrimVertex v2next   = j2.pwlArc.pts[v2nexti];
-    int sgn;
-
-    assert( v1 != v1last );
-    assert( v2 != v2last );
-
-    // the arcs lie on the line (1 == v1.param[1])
-    if( v1.param[1] == v1next.param[1] && v2.param[1] == v2next.param[1] )
-      return 0;
-
-    if( v2next.param[1] < v2.param[1] || v1next.param[1] < v1.param[1] )
-      throw new NurbsException( 28 );
-
-    if( v1.param[0] < v2.param[0] )
-      return 1;
-    else if( v1.param[0] > v2.param[0] )
-      return 0;
-
-    while( 1 ) {
-      if( v1next.param[1] < v2next.param[1] ) {
-        assert( v1.param[1] <= v1next.param[1] );
-        assert( v2.param[1] <= v1next.param[1] );
-        switch( bbox( v2, v2next, v1next, 0 ) ) {
-        case -1:
-          return 1;
-        case 0:
-          sgn = ccw( v1next, v2, v2next );
-          if( sgn != -1 ) {
-            return sgn;
-          } else {
-            v1i = v1nexti--;
-            v1 = j1.pwlArc.pts[v1i];
-            v1next = j1.pwlArc.pts[v1nexti];
-            if( v1 == v1last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 0;
-        }
-      } else if( v1next.param[1] > v2next.param[1] ) {
-        assert( v1.param[1] <= v2next.param[1] );
-        assert( v2.param[1] <= v2next.param[1] );
-        switch( bbox( v1, v1next, v2next, 0 ) ) {
-        case -1:
-          return 0;
-        case 0:
-          sgn = ccw( v1next, v1, v2next );
-          if( sgn != -1 ) { 
-            return sgn;
-          } else {
-            v2i = v2nexti++;
-            v2 = j2.pwlArc.pts[v2i];
-            v2next = j2.pwlArc.pts[v2nexti];
-            if( v2 == v2last ) {
-              return 0; // ill-conditioned, guess answer
-            }
-          }
-          break;
-        case 1:
-          return 1;
-        }
-      } else {
-        if( v1next.param[0] < v2next.param[0] )
-          return 1;
-        else if( v1next.param[0] > v2next.param[0] )
-          return 0;
-        else {
-          v2i = v2nexti++;
-          v2 = j2.pwlArc.pts[v2i];
-          v2next = j2.pwlArc.pts[v2nexti];
-          if( v2 == v2last ) {
-            return 0; // ill-conditioned, guess answer
-          }
-        }
-      }
-    }
-  }
-
-  public void set_domain_distance_u_rate(float u_rate) {
-    domain_distance_u_rate = u_rate;
-  }
-
-  public void set_domain_distance_v_rate(float v_rate) {
-    domain_distance_v_rate = v_rate;
-  }
-
-  public void set_is_domain_distance_sampling(int flag) {
-    is_domain_distance_sampling = flag;
-  }
-
-  //----------------------------------------------------------------------
-  // Internals only below this point
-  //
-
-  /**
-   * Determine which side of a line a jarc lies (for debugging only)
-   */
-  private int arc_classify( Arc jarc, int param, float value )
-  {
-    float tdiff, hdiff;
-    if( param == 0 ) {
-      tdiff = jarc.tail()[0] - value;
-      hdiff = jarc.head()[0] - value;
-    } else {
-      tdiff = jarc.tail()[1] - value;
-      hdiff = jarc.head()[1] - value;
-    }
-
-    if( tdiff > 0.0 ) {
-      if( hdiff > 0.0 ) {
-        return 0x11;
-      } else if( hdiff == 0.0 ) {
-        return 0x12;
-      } else {
-        return 0x10;
-      }
-    } else if( tdiff == 0.0 ) {
-      if( hdiff > 0.0 ) {
-        return 0x21;
-      } else if( hdiff == 0.0 ) {
-        return 0x22;
-      } else {
-        return 0x20;
-      }
-    } else {
-      if( hdiff > 0.0 ) {
-        return 0x01;
-      } else if( hdiff == 0.0 ) {
-        return 0x02;
-      } else {
-        return 0;
-      }
-    }
-  }
-
-  private void classify_headonleft_s( Bin bin, Bin in, Bin out, float val ) {
-    /* tail on line, head at left */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 0, val ) == 0x20 );
-
-      j.setitail();
-
-      float diff = j.prev.tail()[0] - val;
-      if( diff > 0.0 ) {
-        out.addarc( j );
-      } else if( diff < 0.0 ) {
-        if( ccwTurn_sl( j.prev, j ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else {
-        if( j.prev.tail()[1] > j.prev.head()[1] )
-          in.addarc( j );
-        else
-          out.addarc( j );
-      }
-    }
-  }
-
-  private void classify_tailonleft_s( Bin bin, Bin in, Bin out, float val ) {
-    /* tail at left, head on line */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 1, val ) == 0x02 );
-      j.clearitail();
-
-      float diff = j.next.head()[1] - val;
-      if( diff > 0.0 ) {
-        in.addarc( j );
-      } else if( diff < 0.0 ) {
-        if( ccwTurn_tl( j, j.next ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else {
-        if (j.next.tail()[0] > j.next.head()[0] )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      }
-    }
-  }
-
-  private void classify_headonright_s( Bin bin, Bin in, Bin out, float val ) {
-    /* tail on line, head at right */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 0, val ) == 0x21 );
-    
-      j.setitail();
-
-      float diff = j.prev.tail()[0] - val;
-      if( diff > 0.0 ) { 
-        if( ccwTurn_sr( j.prev, j ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else if( diff < 0.0 ) {
-        out.addarc( j );
-      } else {
-        if( j.prev.tail()[1] > j.prev.head()[1] )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      }
-    }
-  }
-
-  private void classify_tailonright_s( Bin bin, Bin in, Bin out, float val ) {
-    /* tail at right, head on line */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 0, val ) == 0x12);
-	
-      j.clearitail();
-
-      float diff = j.next.head()[0] - val;
-      if( diff > 0.0 ) {
-        if( ccwTurn_sr( j, j.next ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else if( diff < 0.0 ) {
-        in.addarc( j );
-      } else {
-        if( j.next.tail()[1] > j.next.head()[1] ) 
-          out.addarc( j );
-        else
-          in.addarc( j );
-      }
-    }
-  }
-
-  private void classify_headonleft_t( Bin bin, Bin in, Bin out, float val ) {
-    /* tail on line, head at left */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 1, val ) == 0x20 );
-      j.setitail();
-
-      float diff = j.prev.tail()[1] - val;
-      if( diff > 0.0 ) {
-        out.addarc( j );
-      } else if( diff < 0.0 ) {
-        if( ccwTurn_tl( j.prev, j ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else {
-        if( j.prev.tail()[0] > j.prev.head()[0] )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      }
-    }
-  }
-
-  private void classify_tailonleft_t( Bin bin, Bin in, Bin out, float val ) {
-    /* tail at left, head on line */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 1, val ) == 0x02 );
-      j.clearitail();
-
-      float diff = j.next.head()[1] - val;
-      if( diff > 0.0 ) {
-        in.addarc( j );
-      } else if( diff < 0.0 ) {
-        if( ccwTurn_tl( j, j.next ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else {
-        if (j.next.tail()[0] > j.next.head()[0] )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      }
-    }
-  }
-
-  private void classify_headonright_t( Bin bin, Bin in, Bin out, float val ) {
-    /* tail on line, head at right */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 1, val ) == 0x21 );
-    
-      j.setitail();
-
-      float diff = j.prev.tail()[1] - val;
-      if( diff > 0.0 ) { 
-        if( ccwTurn_tr( j.prev, j ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else if( diff < 0.0 ) {
-        out.addarc( j );
-      } else {
-        if( j.prev.tail()[0] > j.prev.head()[0] )
-          in.addarc( j );
-        else
-          out.addarc( j );
-      }
-    }
-  }
-
-  private void classify_tailonright_t( Bin bin, Bin in, Bin out, float val ) {
-    /* tail at right, head on line */
-    Arc j;
-
-    while( (j = bin.removearc()) != null ) {
-      assert( arc_classify( j, 1, val ) == 0x12);
-	
-      j.clearitail();
-
-      float diff =  j.next.head()[1] - val;
-      if( diff > 0.0 ) {
-        if( ccwTurn_tr( j, j.next ) != 0 )
-          out.addarc( j );
-        else
-          in.addarc( j );
-      } else if( diff < 0.0 ) { 
-        in.addarc( j );
-      } else {
-        if( j.next.tail()[0] > j.next.head()[0] ) 
-          in.addarc( j );
-        else
-          out.addarc( j );
-      }
-    }
-  }
-
-  private int DIR_DOWN = 0;
-  private int DIR_SAME = 1;
-  private int DIR_UP   = 2;
-  private int DIR_NONE = 3;
-
-  private void tessellate( Arc_ptr, float );
-  private void monotonize( Arc_ptr , Bin & );
-  private int isMonotone( Arc_ptr  );
-  private int decompose( Bin &, float );
-
-
-  private Slicer slicer;
-  private ArcTessellator arctessellator;
-  //  private Pool arcpool;
-  //  private Pool bezierarcpool;
-  //  private Pool pwlarcpool;
-  //  private TrimVertexPool trimvertexpool;
-
-  private JumpBuffer* jumpbuffer;
-  private Renderhints& renderhints;
-  private Backend&  backend;
-
-  private Bin initialbin;
-  private Arc pjarc;
-  private int s_index;
-  private int t_index;
-  private Quilt *qlist;
-  private Flist spbrkpts;
-  private Flist tpbrkpts;
-  private Flist smbrkpts;
-  private Flist tmbrkpts;
-  private float stepsizes[4];
-  private int showDegenerate;
-  private int isArcTypeBezier;
-
-  // FIXME: NOT FINISHED
-  private void samplingSplit( Curvelist&, int );
-
-  private void subdivideInS( Bin source ) {
-    if( renderhints.display_method == N_OUTLINE_PARAM ) {
-      outline( source );
-      freejarcs( source );
-    } else {
-      setArcTypeBezier();
-      setNonDegenerate();
-      splitInS( source, spbrkpts.start, spbrkpts.end );
-    }
-  }
-
-  /**
-   * Splits a patch and a bin by an isoparametric line.
-   */
-  private void splitInS( Bin source, int start, int end ) {
-    if( source.isnonempty() ) {
-      if( start != end ) {
-        int  i = start + (end - start) / 2;
-        Bin left = new Bin();
-        Bin right = new Bin();
-        split( source, left, right, 0, spbrkpts.pts[i] );
-        splitInS( left, start, i );
-        splitInS( right, i+1, end );
-      } else {
-        if( start == spbrkpts.start || start == spbrkpts.end ) {
-          freejarcs( source );
-        } else if( renderhints.display_method == NurbsConsts.N_OUTLINE_PARAM_S ) {
-          outline( source );
-          freejarcs( source );
-        } else {
-          setArcTypeBezier();
-          setNonDegenerate();
-          s_index = start;
-          splitInT( source, tpbrkpts.start, tpbrkpts.end );
-        }
-      }
-    } 
-  }
-
-  /**
-   * Splits a patch and a bin by an isoparametric line.
-   */
-  private void splitInT( Bin source, int start, int end ) {
-    if( source.isnonempty() ) {
-      if( start != end ) {
-        int  i = start + (end - start) / 2;
-        Bin left = new Bin();
-        Bin right = new Bin();
-        split( source, left, right, 1, tpbrkpts.pts[i] );
-        splitInT( left, start, i );
-        splitInT( right, i+1, end );
-      } else {
-        if( start == tpbrkpts.start || start == tpbrkpts.end ) {
-          freejarcs( source );
-        } else if( renderhints.display_method == NurbsConsts.N_OUTLINE_PARAM_ST ) {
-          outline( source );
-          freejarcs( source );
-        } else {
-          t_index = start;
-          setArcTypeBezier();
-          setDegenerate();
-
-          float[] pta = new float[2];
-          float[] ptb = new float[2];
-          pta[0] = spbrkpts.pts[s_index-1];
-          pta[1] = tpbrkpts.pts[t_index-1];
-
-          ptb[0] = spbrkpts.pts[s_index];
-          ptb[1] = tpbrkpts.pts[t_index];
-          qlist.downloadAll( pta, ptb, backend );
-      
-          Patchlist patchlist = new Patchlist( qlist, pta, ptb );
-          /*
-            printf("-------samplingSplit-----\n");
-            source.show("samplingSplit source");
-          */
-          samplingSplit( source, patchlist, renderhints.maxsubdivisions, 0 );
-          setNonDegenerate();
-          setArcTypeBezier();
-        }
-      }
-    } 
-  }
-
-  /**
-   * Recursively subdivides patch, cull checks each subpatch  
-   */
-  private void samplingSplit( Bin source, Patchlist patchlist, int subdivisions, int param ) {
-    if( ! source.isnonempty() ) return;
-
-    if( patchlist.cullCheck() == Defines.CULL_TRIVIAL_REJECT ) {
-      freejarcs( source );
-      return;
-    }
-
-    patchlist.getstepsize();
-
-    if( renderhints.display_method == NurbsConsts.N_OUTLINE_PATCH ) {
-      tessellation( source, patchlist );
-      outline( source );
-      freejarcs( source );
-      return;
-    } 
-
-    //patchlist.clamp();
-
-    tessellation( source, patchlist );
-
-    if( patchlist.needsSamplingSubdivision() && (subdivisions > 0) ) {
-      if( ! patchlist.needsSubdivision( 0 ) )
-        param = 1;
-      else if( ! patchlist.needsSubdivision( 1 ) )
-        param = 0;
-      else
-        param = 1 - param;
-
-      Bin left = new Bin();
-      Bin right = new Bin();
-      float mid = ( patchlist.pspec[param].range[0] +
-                   patchlist.pspec[param].range[1] ) * 0.5;
-      split( source, left, right, param, mid );
-      Patchlist subpatchlist = new Patchlist( patchlist, param, mid );
-      samplingSplit( left, subpatchlist, subdivisions-1, param );
-      samplingSplit( right, patchlist, subdivisions-1, param );
-    } else {
-      setArcTypePwl();
-      setDegenerate();
-      nonSamplingSplit( source, patchlist, subdivisions, param );
-      setDegenerate();
-      setArcTypeBezier();
-    }
-  }
-
-  private void nonSamplingSplit( Bin source, Patchlist patchlist, int subdivisions, int param ) {
-    if( patchlist.needsNonSamplingSubdivision() && (subdivisions > 0) ) {
-      param = 1 - param;
-
-      Bin left = new Bin();
-      Bin right = new Bin();
-      float mid = ( patchlist.pspec[param].range[0] +
-                   patchlist.pspec[param].range[1] ) * 0.5;
-      split( source, left, right, param, mid );
-      Patchlist subpatchlist = new Patchlist( patchlist, param, mid );
-      if( left.isnonempty() )
-        if( subpatchlist.cullCheck() == Defines.CULL_TRIVIAL_REJECT ) 
-          freejarcs( left );
-        else
-          nonSamplingSplit( left, subpatchlist, subdivisions-1, param );
-      if( right.isnonempty() ) 
-        if( patchlist.cullCheck() == Defines.CULL_TRIVIAL_REJECT ) 
-          freejarcs( right );
-        else
-          nonSamplingSplit( right, patchlist, subdivisions-1, param );
-
-    } else {
-      // make bbox calls
-      patchlist.bbox();
-      backend.patch( patchlist.pspec[0].range[0], patchlist.pspec[0].range[1],
-                     patchlist.pspec[1].range[0], patchlist.pspec[1].range[1] );
-    
-      if( renderhints.display_method == NurbsConsts.N_OUTLINE_SUBDIV ) {
-        outline( source );
-        freejarcs( source );
-      } else {
-        setArcTypePwl();
-        setDegenerate();
-        findIrregularS( source );
-        monosplitInS( source, smbrkpts.start, smbrkpts.end );
-      }
-    }
-  }
-
-  /**
-   * Sets tessellation of interior and boundary of patch.
-   */
-  private void tessellation( Bin bin, Patchlist patchlist ) {
-    // tessellate unsampled trim curves
-    tessellate( bin, patchlist.pspec[1].sidestep[1], patchlist.pspec[0].sidestep[1],
-                patchlist.pspec[1].sidestep[0], patchlist.pspec[0].sidestep[0] );
-
-    // set interior sampling rates
-    slicer.setstriptessellation( patchlist.pspec[0].stepsize, patchlist.pspec[1].stepsize );
-
-    //added by zl: set the order which will be used in slicer.c++
-    slicer.set_ulinear( (patchlist.get_uorder() == 2));
-    slicer.set_vlinear( (patchlist.get_vorder() == 2));
-
-    // set boundary sampling rates
-    stepsizes[0] = patchlist.pspec[1].stepsize;
-    stepsizes[1] = patchlist.pspec[0].stepsize;
-    stepsizes[2] = patchlist.pspec[1].stepsize;
-    stepsizes[3] = patchlist.pspec[0].stepsize;
-  }
-
-  /**
-   * Splits a patch and a bin by an isoparametric line.
-   */
-  private void monosplitInS( Bin source, int start, int end ) {
-    if( source.isnonempty() ) {
-      if( start != end ) {
-        int  i = start + (end - start) / 2;
-        Bin left = new Bin();
-        Bin right = new Bin();
-        split( source, left, right, 0, smbrkpts.pts[i] );
-        monosplitInS( left, start, i );
-        monosplitInS( right, i+1, end );
-      } else {
-        if( renderhints.display_method == NurbsConsts.N_OUTLINE_SUBDIV_S ) {
-          outline( source );
-          freejarcs( source );
-        } else {
-          setArcTypePwl();
-          setDegenerate();
-          findIrregularT( source );
-          monosplitInT( source, tmbrkpts.start, tmbrkpts.end );
-        }
-      }
-    } 
-  }
-
-  /**
-   * Splits a patch and a bin by an isoparametric line.
-   */
-  private void monosplitInT( Bin source, int start, int end ) {
-    if( source.isnonempty() ) {
-      if( start != end ) {
-        int  i = start + (end - start) / 2;
-        Bin left = new Bin();
-        Bin right = new Bin();
-        split( source, left, right, 1, tmbrkpts.pts[i] );
-        monosplitInT( left, start, i );
-        monosplitInT( right, i+1, end );
-      } else {
-        if( renderhints.display_method == NurbsConsts.N_OUTLINE_SUBDIV_ST ) {
-          outline( source );
-          freejarcs( source );
-        } else {
-          /*
-            printf("*******render\n");
-            source.show("source\n");
-          */
-          render( source );
-          freejarcs( source );
-        }
-      }
-    } 
-  }
-
-  /**
-   * Renders the trimmed patch by outlining the boundary .
-   */
-  private void outline( Bin bin ) {
-    bin.markall();
-    for( Arc jarc=bin.firstarc(); jarc != null; jarc=bin.nextarc() ) {
-      if( jarc.ismarked() ) {
-        assert( jarc.check( ) );
-        Arc jarchead = jarc;
-        do {
-          slicer.outline( jarc );
-          jarc.clearmark();
-          jarc = jarc.prev;
-        } while (jarc != jarchead);
-      }
-    }
-  }
-
-  /**
-   * Frees all arcs in a bin.
-   */
-  private void freejarcs( Bin & ) {
-    bin.adopt();  /* XXX - should not be necessary */
-
-    Arc jarc;
-    while( (jarc = bin.removearc()) != null ) {
-      if( jarc.pwlArc != null ) jarc.pwlArc.deleteMe( ); jarc.pwlArc = null;
-      if( jarc.bezierArc != null) jarc.bezierArc.deleteMe( ); jarc.bezierArc = null;
-      jarc.deleteMe( );
-    }
-  }
-
-  /**
-   * Renders all monotone regions in a bin and frees the bin.
-   */
-  private void render( Bin bin ) {
-    bin.markall();
-
-    slicer.setisolines( ( renderhints.display_method == N_ISOLINE_S ) ? 1 : 0 );
-
-    for( Arc jarc=bin.firstarc(); jarc != null; jarc=bin.nextarc() ) {
-      if( jarc.ismarked() ) {
-        assert( jarc.check( ) != 0 );
-        Arc jarchead = jarc;
-        do {
-          jarc.clearmark();
-          jarc = jarc.next;
-        } while (jarc != jarchead);
-        slicer.slice( jarc );
-      }
-    }
-  }
-
-  private void split( Bin &, Bin &, Bin &, int, float );
-
-  /**
-   * Tessellates all Bezier arcs in a bin.
-   * <ol>
-   *   <li> only accepts linear Bezier arcs as input 
-   *   <li> the Bezier arcs are stored in the pwlArc structure
-   *   <li> only vertical or horizontal lines work
-   * </ol>
-   * should:
-   * <ol>
-   *   <li> represent Bezier arcs in BezierArc structure
-   *        (this requires a multitude of changes to the code)
-   *   <li> accept high degree Bezier arcs (hard)
-   *   <il> map the curve onto the surface to determine tessellation
-   *   <li> work for curves of arbitrary geometry
-   * </ol>
-   *----------------------------------------------------------------------------
-   */
-  private void tessellate( Bin bin, float rrate, float trate, float lrate, float brate ) {
-    for( Arc jarc=bin.firstarc(); jarc != null; jarc=bin.nextarc() ) {
-      if( jarc.isbezier( ) ) {
-        assert( jarc.pwlArc.npts == 2 );  
-        TrimVertex[] pts = jarc.pwlArc.pts;
-        float s1 = pts[0].param[0];
-        float t1 = pts[0].param[1];
-        float s2 = pts[1].param[0];
-        float t2 = pts[1].param[1];
-      
-        jarc.pwlArc.deleteMe( );
-        jarc.pwlArc = null;
-      
-        switch( jarc.getside() ) {
-        case Arc.SIDE_LEFT:
-          assert( s1 == s2 );
-          arctessellator.pwl_left( jarc, s1, t1, t2, lrate );
-          break;
-        case Arc.SIDE_RIGHT:
-          assert( s1 == s2 );
-          arctessellator.pwl_right( jarc, s1, t1, t2, rrate );
-          break;
-        case Arc.SIDE_TOP:
-          assert( t1 == t2 );
-          arctessellator.pwl_top( jarc, t1, s1, s2, trate );
-          break;
-        case Arc.SIDE_BOTTOM:
-          assert( t1 == t2 );
-          arctessellator.pwl_bottom( jarc, t1, s1, s2, brate );
-          break;
-        case Arc.SIDE_NONE:
-          throw new InternalError("Incorrect tesselation state");
-          break;
-        }
-        assert( ! jarc.isbezier() );
-        assert( jarc.check() != 0 );
-      }
-    }
-  }
-
-  private inline void setDegenerate( void ) { showDegenerate = 1; }
-  private inline void setNonDegenerate( void ) { showDegenerate = 0; }
-  private inline int showingDegenerate( void ) { return showDegenerate; }
-  private inline void setArcTypeBezier( void ) { isArcTypeBezier = 1; }
-  private inline void setArcTypePwl( void ) { isArcTypeBezier = 0; }
-  private inline int isBezierArcType( void ) { return isArcTypeBezier; }
-
-  /**
-   * If no user input trimming data, then create a trimming curve
-   * around the boundaries of the Quilt. The curve consists of four
-   * Jordan arcs, one for each side of the Quilt, connected, of
-   * course, head to tail.
-   */
-  private void makeBorderTrim( float[] from, float[] to ) {
-    float smin = from[0];
-    float smax = to[0];
-    float tmin = from[1];
-    float tmax = to[1];
-
-    pjarc = null;
-
-    Arc jarc = new Arc( Arc.SIDE_BOTTOM, 0 );
-    arctessellator.bezier( jarc, smin, smax, tmin, tmin );
-    initialbin.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-
-    jarc = new Arc( Arc.SIDE_RIGHT, 0 );
-    arctessellator.bezier( jarc, smax, smax, tmin, tmax );
-    initialbin.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-
-    jarc = new Arc( Arc.SIDE_TOP, 0 );
-    arctessellator.bezier( jarc, smax, smin, tmax, tmax );
-    initialbin.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-
-    jarc = new Arc( Arc.SIDE_LEFT, 0 );
-    arctessellator.bezier( jarc, smin, smin, tmax, tmin );
-    initialbin.addarc( jarc  );
-    jarc.append( pjarc );
-
-    assert( jarc.check() );
-  }
-
-  private void split( Bin &, int, const float *, int, int );
-  private void partition( Bin bin, Bin left, Bin intersections, Bin right, Bin unknown, int param, float value ) {
-    Bin  headonleft = new Bin();
-    Bin headonright = new Bin();
-    Bin tailonleft = new Bin();
-    Bin tailonright = new Bin();
-
-    for( Arc jarc = bin.removearc(); jarc != null; jarc = bin.removearc() ) {
-
-      float tdiff = jarc.tail()[param] - value;
-      float hdiff = jarc.head()[param] - value;
-
-      if( tdiff > 0.0 ) {
-        if( hdiff > 0.0 ) {
-          right.addarc( jarc  );
-        } else if( hdiff == 0.0 ) {
-          tailonright.addarc( jarc  );
-        } else {
-          Arc jtemp;
-          switch( arc_split(jarc, param, value, 0) ) {
-          case 2:
-            tailonright.addarc( jarc  );
-            headonleft.addarc( jarc.next  );
-            break;
-          case 31:
-            assert( jarc.head()[param] > value );
-            right.addarc( jarc  );
-            tailonright.addarc( jtemp = jarc.next  );
-            headonleft.addarc( jtemp.next  );
-            break;
-          case 32:
-            assert( jarc.head()[param] <= value );
-            tailonright .addarc( jarc  );
-            headonleft.addarc( jtemp = jarc.next  );
-            left.addarc( jtemp.next  );
-            break;
-          case 4:
-            right.addarc( jarc  );
-            tailonright.addarc( jtemp = jarc.next  );
-            headonleft.addarc( jtemp = jtemp.next  );
-            left.addarc( jtemp.next  );
-          }
-        }
-      } else if( tdiff == 0.0 ) {
-        if( hdiff > 0.0 ) {
-          headonright.addarc( jarc  );
-        } else if( hdiff == 0.0 ) {
-          unknown.addarc( jarc  );
-        } else {
-          headonleft.addarc( jarc  );
-        }
-      } else {
-        if( hdiff > 0.0 ) {
-          Arc jtemp;
-          switch( arc_split(jarc, param, value, 1) ) {
-          case 2:
-            tailonleft.addarc( jarc  );
-            headonright.addarc( jarc.next  );
-            break;
-          case 31:
-            assert( jarc.head()[param] < value );
-            left.addarc( jarc  );
-            tailonleft.addarc( jtemp = jarc.next  );
-            headonright.addarc( jtemp.next  );
-            break;
-          case 32:
-            assert( jarc.head()[param] >= value );
-            tailonleft.addarc( jarc  );
-            headonright.addarc( jtemp = jarc.next  );
-            right.addarc( jtemp.next  );
-            break;
-          case 4:
-            left.addarc( jarc  );
-            tailonleft.addarc( jtemp = jarc.next  );
-            headonright.addarc( jtemp = jtemp.next  );
-            right.addarc( jtemp.next  );
-          }
-        } else if( hdiff == 0.0 ) {
-          tailonleft.addarc( jarc  );
-        } else {
-          left.addarc( jarc  );
-        }
-      }
-    }
-    if( param == 0 ) {
-      classify_headonleft_s( headonleft, intersections, left, value );
-      classify_tailonleft_s( tailonleft, intersections, left, value );
-      classify_headonright_s( headonright, intersections, right, value );
-      classify_tailonright_s( tailonright, intersections, right, value );
-    } else {
-      classify_headonleft_t( headonleft, intersections, left, value );
-      classify_tailonleft_t( tailonleft, intersections, left, value );
-      classify_headonright_t( headonright, intersections, right, value );
-      classify_tailonright_t( tailonright, intersections, right, value );
-    }
-  }
-
-  /**
-   * Determine points of non-monotonicity in s direction.
-   */
-  private void findIrregularS( Bin bin ) {
-    assert( bin.firstarc() == null || bin.firstarc().check() );
-
-    smbrkpts.grow( bin.numarcs() );
-
-    for( Arc jarc=bin.firstarc(); jarc != null; jarc=bin.nextarc() ) {
-      float[] a = jarc.prev.tail();
-      float[] b = jarc.tail();
-      float[] c = jarc.head();
-
-      if( b[1] == a[1] && b[1] == c[1] ) continue;
-
-      //corrected code
-      if((b[1]<=a[1] && b[1] <= c[1]) ||
-         (b[1]>=a[1] && b[1] >= c[1]))
-        {
-          //each arc (jarc, jarc.prev, jarc.next) is a 
-          //monotone arc consisting of multiple line segements.
-          //it may happen that jarc.prev and jarc.next are the same,
-          //that is, jarc.prev and jarc form a closed loop.
-          //In such case, a and c will be the same.
-          if(a[0]==c[0] && a[1] == c[1])
-            {
-              if(jarc.pwlArc.npts >2)
-                {
-                  c = jarc.pwlArc.pts[jarc.pwlArc.npts-2].param;
-                }
-              else
-                {
-                  assert(jarc.prev.pwlArc.npts>2);
-                  a = jarc.prev.pwlArc.pts[jarc.prev.pwlArc.npts-2].param;
-                }
-        
-            }
-          if(area(a,b,c) < 0)
-            {
-              smbrkpts.add(b[0]);
-            }
-
-        }
-
-      /* old code, 
-         if( b[1] <= a[1] && b[1] <= c[1] ) {
-         if( ! ccwTurn_tr( jarc.prev, jarc ) )
-         smbrkpts.add( b[0] );
-         } else if( b[1] >= a[1] && b[1] >= c[1] ) {
-         if( ! ccwTurn_tl( jarc.prev, jarc ) )
-         smbrkpts.add( b[0] );
-         }
-      */
-
-    }
-
-    smbrkpts.filter();
-  }
-
-  /**
-   * Determines points of non-monotonicity in t direction where one
-   * arc is parallel to the s axis.
-   */
-  private void findIrregularT( Bin bin ) {
-    assert( bin.firstarc() == null || bin.firstarc().check() );
-
-    tmbrkpts.grow( bin.numarcs() );
-
-    for( Arc jarc=bin.firstarc(); jarc != null; jarc=bin.nextarc() ) {
-      float[] a = jarc.prev.tail();
-      float[] b = jarc.tail();
-      float[] c = jarc.head();
-
-      if( b[0] == a[0] && b[0] == c[0] ) continue;
-
-      if( b[0] <= a[0] && b[0] <= c[0] ) {
-        if( a[1] != b[1] && b[1] != c[1] ) continue; 
-        if( ccwTurn_sr( jarc.prev, jarc ) == 0)
-          tmbrkpts.add( b[1] );
-      } else if ( b[0] >= a[0] && b[0] >= c[0] ) {
-        if( a[1] != b[1] && b[1] != c[1] ) continue; 
-        if( ccwTurn_sl( jarc.prev, jarc ) == 0)
-          tmbrkpts.add( b[1] );
-      }
-    }
-    tmbrkpts.filter( );
-  }
-
-
-  private int bbox( TrimVertex a, TrimVertex b, TrimVertex c, int p ) {
-    return bbox( a.param[p], b.param[p], c.param[p],
-           a.param[1-p], b.param[1-p], c.param[1-p] );
-  }
-
-  private static int bbox( float sa, float sb, float sc, float ta, float tb, float tc ) {
-    assert( tc >= ta );
-    assert( tc <= tb );
-
-    if( sa < sb ) {
-      if( sc <= sa ) {
-        return -1;
-      } else if( sb <= sc ) {
-        return 1;
-      } else {
-        return 0;
-      }
-    } else if( sa > sb ) {
-      if( sc >= sa ) {
-        return 1;
-      } else if( sb >= sc ) {
-        return -1;
-      } else {
-        return 0;
-      }
-    } else {
-      if( sc > sa ) {
-        return 1;
-      } else if( sb > sc ) {
-        return -1;
-      } else {
-        return 0;
-      }
-    }
-  }
-  /**
-   * Determines how three points are oriented by computing their
-   * determinant.
-   *
-   * @return 1 if the vertices are ccw oriented, 0 if they are cw
-   * oriented, or -1 if the computation is ill-conditioned.
-   */
-  private static int ccw( TrimVertex a, TrimVertex b, TrimVertex c ) {
-    float d = TrimVertex.det3( a, b, c );
-    if( Math.abs(d) < 0.0001 ) return -1;
-    return (d < 0.0) ? 0 : 1;
-  }
-  private void join_s( Bin &, Bin &, Arc_ptr, Arc_ptr  );
-  private void join_t( Bin &, Bin &, Arc_ptr , Arc_ptr  );
-
-  private static void vert_interp( TrimVertex n, TrimVertex l, TrimVertex r, int p, float val ) {
-    assert( val > l.param[p]);
-    assert( val < r.param[p]);
-
-    n.nuid = l.nuid;
-
-    n.param[p] = val;
-    if( l.param[1-p] != r.param[1-p]  ) {
-      float ratio = (val - l.param[p]) / (r.param[p] - l.param[p]);
-      n.param[1-p] = l.param[1-p] + 
-        ratio * (r.param[1-p] - l.param[1-p]);
-    } else {
-      n.param[1-p] = l.param[1-p];
-    }
-  }
-
-  private static final int INTERSECT_VERTEX = 1;
-  private static final int INTERSECT_EDGE   = 2;
-
-  /**
-   * Finds intersection of pwlArc and isoparametric line.
-   */
-  private static int pwlarc_intersect( PwlArc pwlArc, int param, float value, int dir, int[] loc ) {
-    assert( pwlArc.npts > 0 );
-
-    if( dir != 0 ) {
-      TrimVertex[] v = pwlArc.pts;
-      int imin = 0; 
-      int imax = pwlArc.npts - 1;
-      assert( value > v[imin].param[param] );
-      assert( value < v[imax].param[param] );	
-      while( (imax - imin) > 1 ) {
-        int imid = (imax + imin)/2;
-        if( v[imid].param[param] > value )
-          imax = imid;
-        else if( v[imid].param[param] < value )
-          imin = imid;
-        else {
-          loc[1] = imid;
-          return INTERSECT_VERTEX;
-        }
-      }
-      loc[0] = imin;
-      loc[2] = imax;
-      return INTERSECT_EDGE;
-    } else {
-      TrimVertex[] v = pwlArc.pts;
-      int imax = 0; 
-      int imin = pwlArc.npts - 1;
-      assert( value > v[imin].param[param] );
-      assert( value < v[imax].param[param] );	
-      while( (imin - imax) > 1 ) {
-        int imid = (imax + imin)/2;
-        if( v[imid].param[param] > value )
-          imax = imid;
-        else if( v[imid].param[param] < value )
-          imin = imid;
-        else {
-          loc[1] = imid;
-          return INTERSECT_VERTEX;
-        }
-      }
-      loc[0] = imin;
-      loc[2] = imax;
-      return INTERSECT_EDGE;
-    }
-  }
-
-  private int arc_split( Arc jarc , int param, float value, int dir ) {
-    int maxvertex = jarc.pwlArc.npts;
-    Arc jarc1, jarc2, jarc3;
-    TrimVertex v = jarc.pwlArc.pts;
-
-    int[] loc = new int[3];
-    switch( pwlarc_intersect( jarc.pwlArc, param, value, dir, loc ) ) {
-
-      // When the parameter value lands on a vertex, life is sweet
-    case INTERSECT_VERTEX: {
-      jarc1 = new Arc( jarc, new PwlArc( maxvertex-loc[1], /* &v[loc[1]] */ v, loc[1] ) );
-      jarc.pwlArc.npts = loc[1] + 1;
-      jarc1.next = jarc.next;
-      jarc1.next.prev = jarc1;
-      jarc.next = jarc1;
-      jarc1.prev = jarc;
-      assert(jarc.check());
-      return 2;
-    }
-
-      // When the parameter value intersects an edge, we have to
-      // interpolate a new vertex.  There are special cases
-      // if the new vertex is adjacent to one or both of the
-      // endpoints of the arc.
-    case INTERSECT_EDGE: {
-      int i, j;
-      if( dir == 0 ) {
-        i = loc[0];
-        j = loc[2];
-      } else {
-        i = loc[2];
-        j = loc[0];
-      }
-
-      // The split is between vertices at index j and i, in that
-      // order (j < i)
-      
-      // JEB:  This code is my idea of how to do the split without
-      // increasing the number of links.  I'm doing this so that
-      // the is_rect routine can recognize rectangles created by
-      // subdivision.  In exchange for simplifying the curve list,
-      // however, it costs in allocated space and vertex copies.
-      
-      TrimVertex[] newjunk = TrimVertex.allocate(maxvertex -i+1 /*-j*/);
-      int k;
-      for(k=0; k<maxvertex-i; k++)
-        {
-          newjunk[k+1] = v[i+k];
-          newjunk[k+1].nuid = jarc.nuid;
-        }
-      
-      TrimVertex[] vcopy = TrimVertex.allocate(maxvertex);
-      for(k=0; k<maxvertex; k++)
-        {
-          vcopy[k].param[0] = v[k].param[0];
-          vcopy[k].param[1] = v[k].param[1];
-        }
-      jarc.pwlArc.pts=vcopy;
-
-      v[i].nuid = jarc.nuid;
-      v[j].nuid = jarc.nuid;
-      vert_interp( newjunk[0], v[loc[0]], v[loc[2]], param, value );
-
-      if( showingDegenerate() )
-        backend.triangle( v[i], newjunk[0], v[j] );
-
-      vcopy[j+1].param[0]=newjunk[0].param[0];
-      vcopy[j+1].param[1]=newjunk[0].param[1];
-
-
-      jarc1 = new Arc( jarc,
-                       new PwlArc(maxvertex-i+1 , newjunk ) );
-
-      jarc.pwlArc.npts = j+2;
-      jarc1.next = jarc.next;
-      jarc1.next.prev = jarc1;
-      jarc.next = jarc1;
-      jarc1.prev = jarc;
-      assert(jarc.check());
-
-      return 2;
-
-      /***
-      // JEB: This is the original version:
-
-      TrimVertex[] newjunk = TrimVertex.allocate(3);
-      v[i].nuid = jarc.nuid;
-      v[j].nuid = jarc.nuid;
-      newjunk[0] = v[j];
-      newjunk[2] = v[i];
-      vert_interp( &newjunk[1], &v[loc[0]], &v[loc[2]], param, value );
-
-      if( showingDegenerate() )
-        backend.triangle( &newjunk[2], &newjunk[1], &newjunk[0] );
-
-      // New vertex adjacent to both endpoints
-      if (maxvertex == 2) {
-        jarc1 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( 2, newjunk+1 ) );
-        jarc.pwlArc.npts = 2;
-        jarc.pwlArc.pts = newjunk;
-        jarc1.next = jarc.next;
-        jarc1.next.prev = jarc1;
-        jarc.next = jarc1;
-        jarc1.prev = jarc;
-        assert(jarc.check() != 0);
-
-        return 2;
-
-        // New vertex adjacent to ending point of arc
-      } else if (maxvertex - j == 2) {
-        jarc1 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( 2, newjunk ) );
-        jarc2 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( 2, newjunk+1 ) );
-        jarc.pwlArc.npts = maxvertex-1;
-        jarc2.next = jarc.next;
-        jarc2.next.prev = jarc2;
-        jarc.next = jarc1;
-        jarc1.prev = jarc;
-        jarc1.next = jarc2;
-        jarc2.prev = jarc1;
-        assert(jarc.check() != 0);
-        return 31;
-
-        // New vertex adjacent to starting point of arc
-      } else if (i == 1) {
-        jarc1 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( 2, newjunk+1 ) );
-        jarc2 = new(arcpool) Arc( jarc, 
-                                  new(pwlarcpool) PwlArc( maxvertex-1, &jarc.pwlArc.pts[1] ) );
-        jarc.pwlArc.npts = 2;
-        jarc.pwlArc.pts = newjunk;
-        jarc2.next = jarc.next;
-        jarc2.next.prev = jarc2;
-        jarc.next = jarc1;
-        jarc1.prev = jarc;
-        jarc1.next = jarc2;
-        jarc2.prev = jarc1;
-        assert(jarc.check() != 0);
-        return 32;
-
-        // It's somewhere in the middle
-      } else {
-        jarc1 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( 2, newjunk ) );
-        jarc2 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( 2, newjunk+1 ) );
-        jarc3 = new(arcpool) Arc( jarc, new(pwlarcpool) PwlArc( maxvertex-i, v+i ) );
-        jarc.pwlArc.npts = j + 1;
-        jarc3.next = jarc.next;
-        jarc3.next.prev = jarc3;
-        jarc.next = jarc1;
-        jarc1.prev = jarc;
-        jarc1.next = jarc2;
-        jarc2.prev = jarc1;
-        jarc2.next = jarc3;
-        jarc3.prev = jarc2;
-        assert(jarc.check() != 0);
-        return 4;
-      }
-      ***/
-    }
-    default:
-      return -1; //picked -1 since it's not used
-    }
-  }
-
-  private void check_s( Arc_ptr , Arc_ptr  );
-  private void check_t( Arc_ptr , Arc_ptr  );
-  private inline void link( Arc_ptr , Arc_ptr , Arc_ptr , Arc_ptr  );
-  private inline void simple_link( Arc_ptr , Arc_ptr  );
-
-  private Bin makePatchBoundary( const float[] from, const float[] to ) {
-    Bin ret = new Bin();
-    float smin = from[0];
-    float smax = to[0];
-    float tmin = from[1];
-    float tmax = to[1];
-
-    pjarc = 0;
-
-    Arc jarc = new Arc( arc_bottom, 0 );
-    arctessellator.bezier( jarc, smin, smax, tmin, tmin );
-    ret.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-
-    jarc = new(arcpool) Arc( arc_right, 0 );
-    arctessellator.bezier( jarc, smax, smax, tmin, tmax );
-    ret.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-
-    jarc = new(arcpool) Arc( arc_top, 0 );
-    arctessellator.bezier( jarc, smax, smin, tmax, tmax );
-    ret.addarc( jarc  );
-    pjarc = jarc.append( pjarc );
-
-    jarc = new(arcpool) Arc( arc_left, 0 );
-    arctessellator.bezier( jarc, smin, smin, tmax, tmin );
-    ret.addarc( jarc  );
-    jarc.append( pjarc );
-
-    assert( jarc.check() != 0 );
-    return ret;
-  }
-
-   /*in domain distance method, the tessellation is controled by two numbers:
-    *GLU_U_STEP: number of u-segments per unit u length of domain
-    *GLU_V_STEP: number of v-segments per unit v length of domain
-    *These two numbers are normally stored in mapdesc.maxs(t)rate.
-    *I (ZL) put these two numbers here so that I can optimize the untrimmed 
-    *case in the case of domain distance sampling.
-    *These two numbers are set by set_domain_distance_u_rate() and ..._v_..().
-    */
-  private float domain_distance_u_rate;
-  private float domain_distance_v_rate;
-  private int is_domain_distance_sampling;
-  
-}