Added MesaLib-7.6

1 files changed, 1300 insertions, 0 deletions

diff --git a/mesalib/src/glu/sgi/libnurbs/internals/slicer.cc b/mesalib/src/glu/sgi/libnurbs/internals/slicer.cc
new file mode 100644
index 000000000..27d2a650d
--- /dev/null
+++ b/mesalib/src/glu/sgi/libnurbs/internals/slicer.cc
@@ -0,0 +1,1300 @@
+/*
+** 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.
+**
+** 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.
+*/
+
+/*
+ * slicer.c++
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include "glimports.h"
+#include "mystdio.h"
+#include "myassert.h"
+#include "bufpool.h"
+#include "slicer.h"
+#include "backend.h"
+#include "arc.h"
+#include "gridtrimvertex.h"
+#include "simplemath.h"
+#include "trimvertex.h"
+#include "varray.h"
+
+#include "polyUtil.h" //for area()
+
+//static int count=0;
+
+/*USE_OPTTT is initiated in trimvertex.h*/
+
+#ifdef USE_OPTTT
+	#include <GL/gl.h>
+#endif
+
+//#define USE_READ_FLAG //whether to use new or old tesselator
+                          //if defined, it reads "flagFile", 
+                          // if the number is 1, then use new tess
+                          // otherwise, use the old tess.
+                         //if not defined, then use new tess.
+#ifdef USE_READ_FLAG
+static Int read_flag(char* name);
+Int newtess_flag = read_flag("flagFile");
+#endif
+
+//#define COUNT_TRIANGLES
+#ifdef COUNT_TRIANGLES
+Int num_triangles = 0;
+Int num_quads = 0;
+#endif
+
+#define max(a,b) ((a>b)? a:b)
+#define ZERO 0.00001 /*determing whether a loop is a rectngle or not*/
+#define equalRect(a,b) ((glu_abs(a-b) <= ZERO)? 1:0) //only used in tessellating a rectangle
+
+#if 0 // UNUSED
+static Int is_Convex(Arc_ptr loop)
+{
+  if(area(loop->tail(), loop->head(), loop->next->head()) <0 )
+    return 0;
+  for(Arc_ptr jarc = loop->next; jarc != loop; jarc = jarc->next)
+    {
+      if(area(jarc->tail(), jarc->head(), jarc->next->head()) < 0)
+	return 0;
+    }
+  return 1;
+}
+#endif
+
+/******triangulate a monotone polygon**************/
+#include "monoTriangulation.h"
+#if 0 // UNUSED
+static int is_U_monotone(Arc_ptr loop)
+{
+  int n_changes=0;
+  int prev_sign;
+  int cur_sign;
+  Arc_ptr temp;
+
+  cur_sign = compV2InX(loop->head(), loop->tail());
+
+  n_changes  = (compV2InX(loop->prev->head(), loop->prev->tail())
+		!= cur_sign);
+
+  for(temp=loop->next; temp != loop; temp = temp->next)
+    {
+      prev_sign = cur_sign;
+      cur_sign = compV2InX(temp->head(), temp->tail());
+      if(cur_sign != prev_sign)
+       {
+#ifdef DEBUG
+	 printf("***change signe\n");
+#endif
+	 n_changes++;
+       }
+    }
+  if(n_changes == 2) return 1;
+  else
+    return 0;
+}
+#endif
+
+inline int compInY(REAL a[2], REAL b[2])
+{
+  if(a[1] < b[1])
+    return -1;
+  else if (a[1] > b[1])
+    return 1;
+  else if(a[0] > b[0])
+    return 1;
+  else return -1;
+}
+
+void monoTriangulationLoop(Arc_ptr loop, Backend& backend, primStream* pStream)
+{
+  int i;
+  //find the top, bottom, increasing and decreasing chain
+  //then call monoTrianulation
+  Arc_ptr jarc, temp;
+  Arc_ptr top;
+  Arc_ptr bot;
+  top = bot = loop;
+  if(compInY(loop->tail(), loop->prev->tail()) < 0)
+    {
+      //first find bot
+      for(temp = loop->next; temp != loop; temp = temp->next)
+	{
+	  if(compInY(temp->tail(), temp->prev->tail()) > 0)
+	    break;
+	}
+      bot = temp->prev;
+      //then find top
+      for(temp=loop->prev; temp != loop; temp = temp->prev)
+	{
+	  if(compInY(temp->tail(), temp->prev->tail()) > 0)
+	    break;
+	}
+      top = temp;
+    }
+  else //loop > loop->prev
+    {
+      for(temp=loop->next; temp != loop; temp = temp->next)
+	{
+	  if(compInY(temp->tail(), temp->prev->tail()) < 0)
+	    break;
+	}
+      top = temp->prev;
+      for(temp=loop->prev; temp != loop; temp = temp->prev)
+	{
+	  if(compInY(temp->tail(), temp->prev->tail()) < 0)
+	    break;
+	}
+      bot = temp;
+    }
+  //creat increase and decrease chains
+  vertexArray inc_chain(50); //this is a dynamci array
+  for(i=1; i<=top->pwlArc->npts-2; i++) 
+    {
+      //the first vertex is the top which doesn't below to inc_chain
+      inc_chain.appendVertex(top->pwlArc->pts[i].param);
+    }
+  for(jarc=top->next; jarc != bot; jarc = jarc->next)
+    {
+      for(i=0; i<=jarc->pwlArc->npts-2; i++)
+	{
+	  inc_chain.appendVertex(jarc->pwlArc->pts[i].param);
+	}
+      
+    }
+  vertexArray dec_chain(50);
+  for(jarc = top->prev; jarc != bot; jarc = jarc->prev)
+    {
+      for(i=jarc->pwlArc->npts-2; i>=0; i--)
+	{
+	  dec_chain.appendVertex(jarc->pwlArc->pts[i].param);
+	}
+    }
+  for(i=bot->pwlArc->npts-2; i>=1; i--)
+    {
+      dec_chain.appendVertex(jarc->pwlArc->pts[i].param);
+    }	  
+
+  monoTriangulationRec(top->tail(), bot->tail(), &inc_chain, 0,
+		       &dec_chain, 0, &backend);
+
+}
+
+/********tesselate a rectanlge (OPTIMIZATION**************/
+static void triangulateRectGen(Arc_ptr loop, int n_ulines, int n_vlines, Backend& backend);
+
+static Int is_rect(Arc_ptr loop)
+{
+  Int nlines =1;
+  for(Arc_ptr jarc = loop->next; jarc != loop; jarc = jarc->next)
+    {
+      nlines++;
+      if(nlines == 5)
+	break;
+    }
+  if(nlines != 4)
+    return 0;
+
+
+/*
+printf("here1\n");
+printf("loop->tail=(%f,%f)\n", loop->tail()[0], loop->tail()[1]);
+printf("loop->head=(%f,%f)\n", loop->head()[0], loop->head()[1]);
+printf("loop->next->tail=(%f,%f)\n", loop->next->tail()[0], loop->next->tail()[1]);
+printf("loop->next->head=(%f,%f)\n", loop->next->head()[0], loop->next->head()[1]);
+if(fglu_abs(loop->tail()[0] - loop->head()[0])<0.000001)
+	printf("equal 1\n");
+if(loop->next->tail()[1] == loop->next->head()[1])
+	printf("equal 2\n");
+*/
+
+  if( (glu_abs(loop->tail()[0] - loop->head()[0])<=ZERO) && 
+      (glu_abs(loop->next->tail()[1] - loop->next->head()[1])<=ZERO) &&
+      (glu_abs(loop->prev->tail()[1] - loop->prev->head()[1])<=ZERO) &&
+      (glu_abs(loop->prev->prev->tail()[0] - loop->prev->prev->head()[0])<=ZERO)
+     )
+    return 1;
+  else if
+    ( (glu_abs(loop->tail()[1] - loop->head()[1]) <= ZERO) && 
+      (glu_abs(loop->next->tail()[0] - loop->next->head()[0]) <= ZERO) &&
+      (glu_abs(loop->prev->tail()[0] - loop->prev->head()[0]) <= ZERO) &&
+      (glu_abs(loop->prev->prev->tail()[1] - loop->prev->prev->head()[1]) <= ZERO)
+     )
+      return 1;
+  else
+    return 0;
+}
+
+
+//a line with the same u for opt
+#ifdef USE_OPTTT
+static void evalLineNOGE_BU(TrimVertex *verts, int n, Backend& backend)
+{
+  int i;
+  backend.preEvaluateBU(verts[0].param[0]);
+  for(i=0; i<n; i++)
+    backend.tmeshvertNOGE_BU(&verts[i]);
+}
+#endif
+
+//a line with the same v for opt
+#ifdef USE_OPTTT
+static void evalLineNOGE_BV(TrimVertex *verts, int n, Backend& backend)
+{
+  int i;
+  backend.preEvaluateBV(verts[0].param[1]);
+
+  for(i=0; i<n; i++)
+    backend.tmeshvertNOGE_BV(&verts[i]);
+}
+#endif
+
+#ifdef USE_OPTTT
+static void evalLineNOGE(TrimVertex *verts, int n, Backend& backend)
+{
+
+  if(verts[0].param[0] == verts[n-1].param[0]) //all u;s are equal
+    evalLineNOGE_BU(verts, n, backend);
+  else if(verts[0].param[1] == verts[n-1].param[1]) //all v's are equal
+    evalLineNOGE_BV(verts, n, backend);
+  else
+    {
+      int i;
+      for(i=0; i<n; i++)
+	backend.tmeshvertNOGE(&verts[i]);
+    }
+}
+#endif
+
+inline void  OPT_OUTVERT(TrimVertex& vv, Backend& backend) 
+{
+
+#ifdef USE_OPTTT
+  glNormal3fv(vv.cache_normal);                         
+  glVertex3fv(vv.cache_point);
+#else
+
+  backend.tmeshvert(&vv);
+
+#endif
+
+}
+
+static void triangulateRectAux(PwlArc* top, PwlArc* bot, PwlArc* left, PwlArc* right, Backend& backend);
+
+static void triangulateRect(Arc_ptr loop, Backend& backend, int TB_or_LR, int ulinear, int vlinear)
+{
+  //we know the loop is a rectangle, but not sure which is top
+  Arc_ptr top, bot, left, right;
+  if(loop->tail()[1] == loop->head()[1])
+    {
+      if(loop->tail()[1] > loop->prev->prev->tail()[1])
+	{
+
+	top = loop;
+	}
+      else{
+
+	top = loop->prev->prev;
+	}
+    }
+  else 
+    {
+      if(loop->tail()[0] > loop->prev->prev->tail()[0])
+	{
+	  //loop is the right arc
+
+	  top = loop->next;
+	}
+      else
+	{
+
+	  top = loop->prev;
+	}
+    }
+  left = top->next;
+  bot  = left->next;
+  right= bot->next;
+
+  //if u, v are both nonlinear, then if the
+  //boundary is tessellated dense, we also
+  //sample the inside to get a better tesslletant.
+  if( (!ulinear) && (!vlinear))
+    {
+      int nu = top->pwlArc->npts;
+      if(nu < bot->pwlArc->npts)
+	nu = bot->pwlArc->npts;
+      int nv = left->pwlArc->npts;
+      if(nv < right->pwlArc->npts)
+	nv = right->pwlArc->npts;
+/*
+      if(nu > 2 && nv > 2)
+	{
+	  triangulateRectGen(top, nu-2,  nv-2, backend);
+	  return;
+	}
+*/
+    }
+
+  if(TB_or_LR == 1)
+    triangulateRectAux(top->pwlArc, bot->pwlArc, left->pwlArc, right->pwlArc, backend);
+  else if(TB_or_LR == -1)
+    triangulateRectAux(left->pwlArc, right->pwlArc, bot->pwlArc, top->pwlArc, backend);    
+  else
+    {
+      Int maxPointsTB = top->pwlArc->npts + bot->pwlArc->npts;
+      Int maxPointsLR = left->pwlArc->npts + right->pwlArc->npts;
+      
+      if(maxPointsTB < maxPointsLR)
+	triangulateRectAux(left->pwlArc, right->pwlArc, bot->pwlArc, top->pwlArc, backend);    
+      else
+	triangulateRectAux(top->pwlArc, bot->pwlArc, left->pwlArc, right->pwlArc, backend);
+    }
+}
+
+static void triangulateRectAux(PwlArc* top, PwlArc* bot, PwlArc* left, PwlArc* right, Backend& backend)
+{ //if(maxPointsTB >= maxPointsLR)
+    {
+
+      Int d, topd_left, topd_right, botd_left, botd_right, i,j;
+      d = left->npts /2;
+
+#ifdef USE_OPTTT
+      evalLineNOGE(top->pts, top->npts, backend);
+      evalLineNOGE(bot->pts, bot->npts, backend);
+      evalLineNOGE(left->pts, left->npts, backend);
+      evalLineNOGE(right->pts, right->npts, backend);
+#endif
+
+      if(top->npts == 2) {
+	backend.bgntfan();
+	OPT_OUTVERT(top->pts[0], backend);//the root
+	for(i=0; i<left->npts; i++){
+	  OPT_OUTVERT(left->pts[i], backend);
+	}
+	for(i=1; i<= bot->npts-2; i++){
+	  OPT_OUTVERT(bot->pts[i], backend);
+	}
+	backend.endtfan();
+	
+	backend.bgntfan();
+	OPT_OUTVERT(bot->pts[bot->npts-2], backend);
+	for(i=0; i<right->npts; i++){
+	  OPT_OUTVERT(right->pts[i], backend);
+	}
+	backend.endtfan();
+      }
+      else if(bot->npts == 2) {
+	backend.bgntfan();
+	OPT_OUTVERT(bot->pts[0], backend);//the root
+	for(i=0; i<right->npts; i++){
+	  OPT_OUTVERT(right->pts[i], backend);
+	}
+	for(i=1; i<= top->npts-2; i++){
+	  OPT_OUTVERT(top->pts[i], backend);
+	}
+	backend.endtfan();
+	
+	backend.bgntfan();
+	OPT_OUTVERT(top->pts[top->npts-2], backend);
+	for(i=0; i<left->npts; i++){
+	  OPT_OUTVERT(left->pts[i], backend);
+	}
+	backend.endtfan();
+      }
+      else { //both top and bot have >=3 points
+	
+	backend.bgntfan();
+	
+	OPT_OUTVERT(top->pts[top->npts-2], backend);
+	
+	for(i=0; i<=d; i++)
+	  {
+	    OPT_OUTVERT(left->pts[i], backend);	  
+	  }
+	backend.endtfan();
+	
+	backend.bgntfan();
+	
+	OPT_OUTVERT(bot->pts[1], backend);
+	
+	OPT_OUTVERT(top->pts[top->npts-2], backend);
+	
+	for(i=d; i< left->npts; i++)
+	  {      
+	    OPT_OUTVERT(left->pts[i], backend);      
+	  }
+	backend.endtfan();
+
+	d = right->npts/2;
+	//output only when d<right->npts-1 and
+	//
+	if(d<right->npts-1)
+	  {	
+	    backend.bgntfan();
+	    //      backend.tmeshvert(& top->pts[1]);
+	    OPT_OUTVERT(top->pts[1], backend);
+	    for(i=d; i< right->npts; i++)
+	      {
+		//	  backend.tmeshvert(& right->pts[i]);
+		
+		OPT_OUTVERT(right->pts[i], backend);
+		
+	      }
+	    backend.endtfan();
+	  }
+	
+	backend.bgntfan();
+	//      backend.tmeshvert(& bot->pts[bot->npts-2]);
+	OPT_OUTVERT( bot->pts[bot->npts-2], backend);
+	for(i=0; i<=d; i++)
+	  {
+	    //	  backend.tmeshvert(& right->pts[i]);
+	    OPT_OUTVERT(right->pts[i], backend);
+	    
+	  }
+	
+	//      backend.tmeshvert(& top->pts[1]);
+	OPT_OUTVERT(top->pts[1], backend);      
+	
+	backend.endtfan();
+
+
+	topd_left = top->npts-2;
+	topd_right = 1; //topd_left>= topd_right
+
+	botd_left = 1;
+	botd_right = bot->npts-2; //botd_left<= bot_dright
+
+	
+	if(top->npts < bot->npts)
+	  {
+	    int delta=bot->npts - top->npts;
+	    int u = delta/2;
+	    botd_left = 1+ u;
+	    botd_right = bot->npts-2-( delta-u);	    
+	
+	    if(botd_left >1)
+	      {
+		backend.bgntfan();
+		//	  backend.tmeshvert(& top->pts[top->npts-2]);
+		OPT_OUTVERT(top->pts[top->npts-2], backend);
+		for(i=1; i<= botd_left; i++)
+		  {
+		    //	      backend.tmeshvert(& bot->pts[i]);
+		    OPT_OUTVERT(bot->pts[i] , backend);
+		  }
+		backend.endtfan();
+	      }
+	    if(botd_right < bot->npts-2)
+	      {
+		backend.bgntfan();
+		OPT_OUTVERT(top->pts[1], backend);
+		for(i=botd_right; i<= bot->npts-2; i++)
+		  OPT_OUTVERT(bot->pts[i], backend);
+		backend.endtfan();
+	      }
+	  }
+	else if(top->npts> bot->npts)
+	  {
+	    int delta=top->npts-bot->npts;
+	    int u = delta/2;
+	    topd_left = top->npts-2 - u;
+	    topd_right = 1+delta-u;
+	    
+	    if(topd_left < top->npts-2)
+	      {
+		backend.bgntfan();
+		//	  backend.tmeshvert(& bot->pts[1]);
+		OPT_OUTVERT(bot->pts[1], backend);
+		for(i=topd_left; i<= top->npts-2; i++)
+		  {
+		    //	      backend.tmeshvert(& top->pts[i]);
+		    OPT_OUTVERT(top->pts[i], backend);
+		  }
+		backend.endtfan();
+	      }
+	    if(topd_right > 1)
+	      {
+		backend.bgntfan();
+		OPT_OUTVERT(bot->pts[bot->npts-2], backend);
+		for(i=1; i<= topd_right; i++)
+		  OPT_OUTVERT(top->pts[i], backend);
+		backend.endtfan();
+	      }
+	  }
+	
+	if(topd_left <= topd_right) 
+	  return;
+
+	backend.bgnqstrip();
+	for(j=botd_left, i=topd_left; i>=topd_right; i--,j++)
+	  {
+	    //	  backend.tmeshvert(& top->pts[i]);
+	    //	  backend.tmeshvert(& bot->pts[j]);
+	    OPT_OUTVERT(top->pts[i], backend);
+	    OPT_OUTVERT(bot->pts[j], backend);
+	  }
+	backend.endqstrip();
+	
+      }
+    }
+}
+
+  
+static void triangulateRectCenter(int n_ulines, REAL* u_val, 
+				  int n_vlines, REAL* v_val,
+				  Backend& backend)
+{
+
+  // XXX this code was patched by Diego Santa Cruz <Diego.SantaCruz@epfl.ch>
+  // to fix a problem in which glMapGrid2f() was called with bad parameters.
+  // This has beens submitted to SGI but not integrated as of May 1, 2001.
+  if(n_ulines>1 && n_vlines>1) {
+    backend.surfgrid(u_val[0], u_val[n_ulines-1], n_ulines-1, 
+                     v_val[n_vlines-1], v_val[0], n_vlines-1);
+    backend.surfmesh(0,0,n_ulines-1,n_vlines-1);
+  }
+
+  return;
+
+  /*
+  for(i=0; i<n_vlines-1; i++)
+    {
+
+      backend.bgnqstrip();
+      for(j=0; j<n_ulines; j++)
+	{
+	  trimVert.param[0] = u_val[j];
+	  trimVert.param[1] = v_val[i+1];
+	  backend.tmeshvert(& trimVert);	  
+
+	  trimVert.param[1] = v_val[i];
+	  backend.tmeshvert(& trimVert);	  
+	}
+      backend.endqstrip();
+
+    }
+    */
+}
+
+//it works for top, bot, left ad right, you need ot select correct arguments
+static void triangulateRectTopGen(Arc_ptr arc, int n_ulines, REAL* u_val, Real v, int dir, int is_u, Backend& backend)
+{
+
+  if(is_u)
+    {
+      int i,k;
+      REAL* upper_val = (REAL*) malloc(sizeof(REAL) * arc->pwlArc->npts);
+      assert(upper_val);
+      if(dir)
+	{
+	  for(k=0,i=arc->pwlArc->npts-1; i>=0; i--,k++)
+	    {
+	      upper_val[k] = arc->pwlArc->pts[i].param[0];
+	    }	
+	  backend.evalUStrip(arc->pwlArc->npts, arc->pwlArc->pts[0].param[1],
+			     upper_val,
+			     n_ulines, v, u_val);
+	}
+      else
+	{
+	  for(k=0,i=0;  i<arc->pwlArc->npts; i++,k++)
+	    {
+	      upper_val[k] = arc->pwlArc->pts[i].param[0];
+
+	    }		  
+
+	  backend.evalUStrip(
+			     n_ulines, v, u_val,
+			     arc->pwlArc->npts, arc->pwlArc->pts[0].param[1], upper_val
+			     );	 
+	}
+
+      free(upper_val);
+      return;
+    }
+  else //is_v
+    {
+      int i,k;
+      REAL* left_val = (REAL*) malloc(sizeof(REAL) * arc->pwlArc->npts);
+      assert(left_val);   
+      if(dir)
+	{
+	  for(k=0,i=arc->pwlArc->npts-1; i>=0; i--,k++)
+	    {
+	      left_val[k] = arc->pwlArc->pts[i].param[1];
+	    }
+	  backend.evalVStrip(arc->pwlArc->npts, arc->pwlArc->pts[0].param[0],
+			     left_val,
+			     n_ulines, v, u_val);
+	}
+      else 
+	{
+	  for(k=0,i=0;  i<arc->pwlArc->npts; i++,k++)
+	    {
+	      left_val[k] = arc->pwlArc->pts[i].param[1];
+	    }
+	   backend.evalVStrip(
+			     n_ulines, v, u_val,
+			     arc->pwlArc->npts, arc->pwlArc->pts[0].param[0], left_val
+			     );	
+	}
+      free(left_val);
+      return;
+    }
+	
+  //the following is a different version of the above code. If you comment
+  //the above code, the following code will still work. The reason to leave
+  //the folliwng code here is purely for testing purpose.
+  /*
+  int i,j;
+  PwlArc* parc = arc->pwlArc;
+  int d1 = parc->npts-1;
+  int d2 = 0;
+  TrimVertex trimVert;
+  trimVert.nuid = 0;//????
+  REAL* temp_u_val = u_val;
+  if(dir ==0) //have to reverse u_val
+    {
+      temp_u_val = (REAL*) malloc(sizeof(REAL) * n_ulines);
+      assert(temp_u_val);
+      for(i=0; i<n_ulines; i++)
+	temp_u_val[i] = u_val[n_ulines-1-i];
+    }
+  u_val = temp_u_val;
+
+  if(parc->npts > n_ulines)
+    {
+      d1 = n_ulines-1;
+
+      backend.bgntfan();
+      if(is_u){
+	trimVert.param[0] = u_val[0];
+	trimVert.param[1] = v;
+      }
+      else
+	{
+	trimVert.param[1] = u_val[0];
+	trimVert.param[0] = v;
+      }
+	  
+      backend.tmeshvert(& trimVert);
+      for(i=d1; i< parc->npts; i++)
+	backend.tmeshvert(& parc->pts[i]);
+      backend.endtfan();
+
+
+    }
+  else if(parc->npts < n_ulines)
+    {
+      d2 = n_ulines-parc->npts;
+
+
+      backend.bgntfan();
+      backend.tmeshvert(& parc->pts[parc->npts-1]);
+      for(i=0; i<= d2; i++)
+	{
+	  if(is_u){
+	    trimVert.param[0] = u_val[i];
+	    trimVert.param[1] = v;
+	  }
+	  else
+	    {
+	      trimVert.param[1] = u_val[i];
+	      trimVert.param[0] = v;
+	    }
+	  backend.tmeshvert(&trimVert);
+	}
+      backend.endtfan();
+
+    }
+  if(d1>0){
+
+
+    backend.bgnqstrip();
+    for(i=d1, j=d2; i>=0; i--, j++)
+      {
+	backend.tmeshvert(& parc->pts[i]);
+
+	if(is_u){
+	  trimVert.param[0] = u_val[j];
+	  trimVert.param[1] = v;
+	}
+	else{
+	  trimVert.param[1] = u_val[j];
+	  trimVert.param[0] = v;
+	}
+	backend.tmeshvert(&trimVert);
+
+
+	
+      }
+    backend.endqstrip();
+
+
+  }
+  if(dir == 0)  //temp_u_val was mallocated
+    free(temp_u_val);
+ */
+}
+
+//n_ulines is the number of ulines inside, and n_vlines is the number of vlines
+//inside, different from meanings elsewhere!!!
+static void triangulateRectGen(Arc_ptr loop, int n_ulines, int n_vlines, Backend& backend)
+{
+
+  int i;
+  //we know the loop is a rectangle, but not sure which is top
+  Arc_ptr top, bot, left, right;
+
+  if(equalRect(loop->tail()[1] ,  loop->head()[1]))
+    {
+
+      if(loop->tail()[1] > loop->prev->prev->tail()[1])
+	{
+
+	top = loop;
+	}
+      else{
+
+	top = loop->prev->prev;
+	}
+    }
+  else 
+    {
+      if(loop->tail()[0] > loop->prev->prev->tail()[0])
+	{
+	  //loop is the right arc
+
+	  top = loop->next;
+	}
+      else
+	{
+
+	  top = loop->prev;
+	}
+    }
+
+  left = top->next;
+  bot  = left->next;
+  right= bot->next;
+
+#ifdef COUNT_TRIANGLES
+  num_triangles += loop->pwlArc->npts + 
+                 left->pwlArc->npts + 
+                 bot->pwlArc->npts + 
+		  right->pwlArc->npts 
+		      + 2*n_ulines + 2*n_vlines 
+			-8;
+  num_quads += (n_ulines-1)*(n_vlines-1);
+#endif
+/*
+  backend.surfgrid(left->tail()[0], right->tail()[0], n_ulines+1, 
+		   top->tail()[1], bot->tail()[1], n_vlines+1);
+//  if(n_ulines>1 && n_vlines>1)
+    backend.surfmesh(0,0,n_ulines+1,n_vlines+1);
+return;
+*/
+  REAL* u_val=(REAL*) malloc(sizeof(REAL)*n_ulines);
+  assert(u_val);
+  REAL* v_val=(REAL*)malloc(sizeof(REAL) * n_vlines);
+  assert(v_val);
+  REAL u_stepsize = (right->tail()[0] - left->tail()[0])/( (REAL) n_ulines+1);
+  REAL v_stepsize = (top->tail()[1] - bot->tail()[1])/( (REAL) n_vlines+1);
+  Real temp=left->tail()[0]+u_stepsize;
+  for(i=0; i<n_ulines; i++)
+    {
+      u_val[i] = temp;
+      temp += u_stepsize;
+    }
+  temp = bot->tail()[1] + v_stepsize;
+  for(i=0; i<n_vlines; i++)
+    {
+      v_val[i] = temp;
+      temp += v_stepsize;
+    }
+
+  triangulateRectTopGen(top, n_ulines, u_val, v_val[n_vlines-1], 1,1, backend);
+  triangulateRectTopGen(bot, n_ulines, u_val, v_val[0], 0, 1, backend);
+  triangulateRectTopGen(left, n_vlines, v_val, u_val[0], 1, 0, backend);
+  triangulateRectTopGen(right, n_vlines, v_val, u_val[n_ulines-1], 0,0, backend);
+
+
+
+
+  //triangulate the center
+  triangulateRectCenter(n_ulines, u_val, n_vlines, v_val, backend);
+
+  free(u_val);
+  free(v_val);
+  
+}
+
+
+  
+
+/**********for reading newtess_flag from a file**********/
+#ifdef USE_READ_FLAG
+static Int read_flag(char* name)
+{
+  Int ret;
+  FILE* fp = fopen(name, "r");
+  if(fp == NULL)
+    {
+      fprintf(stderr, "can't open file %s\n", name);
+      exit(1);
+    }
+  fscanf(fp, "%i", &ret);
+  fclose(fp);
+  return ret;
+}
+#endif  
+
+/***********nextgen tess****************/
+#include "sampleMonoPoly.h"
+directedLine* arcToDLine(Arc_ptr arc)
+{
+  int i;
+  Real vert[2];
+  directedLine* ret;
+  sampledLine* sline = new sampledLine(arc->pwlArc->npts);
+  for(i=0; i<arc->pwlArc->npts; i++)
+    {
+      vert[0] = arc->pwlArc->pts[i].param[0];
+      vert[1] = arc->pwlArc->pts[i].param[1];
+      sline->setPoint(i, vert);
+    }
+  ret = new directedLine(INCREASING, sline);
+  return ret;
+}
+ 
+/*an pwlArc may not be a straight line*/
+directedLine* arcToMultDLines(directedLine* original, Arc_ptr arc)
+{
+  directedLine* ret = original;
+  int is_linear = 0;
+  if(arc->pwlArc->npts == 2 )
+    is_linear = 1;
+  else if(area(arc->pwlArc->pts[0].param, arc->pwlArc->pts[1].param, arc->pwlArc->pts[arc->pwlArc->npts-1].param) == 0.0)
+    is_linear = 1;
+  
+  if(is_linear)
+    {
+      directedLine *dline = arcToDLine(arc);
+      if(ret == NULL)
+	ret = dline;
+      else
+	ret->insert(dline);
+      return ret;
+    }
+  else /*not linear*/
+    {
+      for(Int i=0; i<arc->pwlArc->npts-1; i++)
+	{
+	  Real vert[2][2];
+	  vert[0][0] = arc->pwlArc->pts[i].param[0];
+	  vert[0][1] = arc->pwlArc->pts[i].param[1];
+	  vert[1][0] = arc->pwlArc->pts[i+1].param[0];
+	  vert[1][1] = arc->pwlArc->pts[i+1].param[1];
+	  
+	  sampledLine *sline = new sampledLine(2, vert);
+	  directedLine *dline = new directedLine(INCREASING, sline);
+	  if(ret == NULL)
+	    ret = dline;
+	  else
+	    ret->insert(dline);
+	}
+      return ret;
+    }
+}
+  
+     
+	
+directedLine* arcLoopToDLineLoop(Arc_ptr loop)
+{
+  directedLine* ret;
+
+  if(loop == NULL)
+    return NULL;
+  ret = arcToMultDLines(NULL, loop);
+//ret->printSingle();
+  for(Arc_ptr temp = loop->next; temp != loop; temp = temp->next){
+    ret = arcToMultDLines(ret, temp);
+//ret->printSingle();
+  }
+
+  return ret;
+}
+
+/*
+void Slicer::evalRBArray(rectBlockArray* rbArray, gridWrap* grid)
+{
+  TrimVertex *trimVert = (TrimVertex*)malloc(sizeof(TrimVertex));
+  trimVert -> nuid = 0;//????
+
+  Real* u_values = grid->get_u_values();
+  Real* v_values = grid->get_v_values();
+
+  Int i,j,k,l;
+
+  for(l=0; l<rbArray->get_n_elements(); l++)
+    {
+      rectBlock* block = rbArray->get_element(l);
+      for(k=0, i=block->get_upGridLineIndex(); i>block->get_lowGridLineIndex(); i--, k++)
+	{
+
+	  backend.bgnqstrip();
+	  for(j=block->get_leftIndices()[k+1]; j<= block->get_rightIndices()[k+1]; j++)
+	    {
+	      trimVert->param[0] = u_values[j];
+	      trimVert->param[1] = v_values[i];
+	      backend.tmeshvert(trimVert);
+
+	      trimVert->param[1] = v_values[i-1];
+	      backend.tmeshvert(trimVert);
+
+	    }
+	  backend.endqstrip();
+
+	}
+    }
+  
+  free(trimVert);
+}
+*/
+
+void Slicer::evalRBArray(rectBlockArray* rbArray, gridWrap* grid)
+{
+  Int i,j,k;
+  
+  Int n_vlines=grid->get_n_vlines();
+  //the reason to switch the position of v_max and v_min is because of the
+  //the orientation problem. glEvalMesh generates quad_strip clockwise, but
+  //we need counter-clockwise.
+  backend.surfgrid(grid->get_u_min(), grid->get_u_max(), grid->get_n_ulines()-1,
+		   grid->get_v_max(), grid->get_v_min(), n_vlines-1);
+
+
+  for(j=0; j<rbArray->get_n_elements(); j++)
+    {
+      rectBlock* block = rbArray->get_element(j);
+      Int low = block->get_lowGridLineIndex();
+      Int high = block->get_upGridLineIndex();
+
+      for(k=0, i=high; i>low; i--, k++)
+	{
+	  backend.surfmesh(block->get_leftIndices()[k+1], n_vlines-1-i, block->get_rightIndices()[k+1]-block->get_leftIndices()[k+1], 1);
+	}
+    }
+}
+
+
+void Slicer::evalStream(primStream* pStream)
+{
+  Int i,j,k;
+  k=0;
+/*  TrimVertex X;*/
+  TrimVertex *trimVert =/*&X*/  (TrimVertex*)malloc(sizeof(TrimVertex));
+  trimVert -> nuid = 0;//???
+  Real* vertices = pStream->get_vertices(); //for efficiency
+  for(i=0; i<pStream->get_n_prims(); i++)
+    {
+
+     //ith primitive  has #vertices = lengths[i], type=types[i]
+      switch(pStream->get_type(i)){
+      case PRIMITIVE_STREAM_FAN:
+
+	backend.bgntfan();
+
+	for(j=0; j<pStream->get_length(i); j++)
+	  {	    
+	    trimVert->param[0] = vertices[k];
+	    trimVert->param[1] = vertices[k+1];
+	    backend.tmeshvert(trimVert);	   
+	    
+//	    backend.tmeshvert(vertices[k], vertices[k+1]);
+	    k += 2;
+	  }
+	backend.endtfan();
+	break;
+	
+      default:
+	fprintf(stderr, "evalStream: not implemented yet\n");
+	exit(1);
+
+      }
+    }
+  free(trimVert);
+}
+	   
+	   
+	    
+
+void Slicer::slice_new(Arc_ptr loop)
+{
+//count++;
+//if(count == 78) count=1;
+//printf("count=%i\n", count);
+//if( ! (4<= count && count <=4)) return;
+
+
+  Int num_ulines;
+  Int num_vlines;
+  Real uMin, uMax, vMin, vMax;
+  Real mydu, mydv;
+  uMin = uMax = loop->tail()[0];
+  vMin = vMax = loop->tail()[1];
+  mydu = (du>0)? du: -du;
+  mydv = (dv>0)? dv: -dv;
+
+  for(Arc_ptr jarc=loop->next; jarc != loop; jarc = jarc->next)
+   {
+
+     if(jarc->tail()[0] < uMin)
+       uMin = jarc->tail()[0];
+     if(jarc->tail()[0] > uMax)
+       uMax = jarc->tail()[0];
+     if(jarc->tail()[1] < vMin)
+       vMin = jarc->tail()[1];
+     if(jarc->tail()[1] > vMax)
+       vMax = jarc->tail()[1];
+   }
+
+  if (uMax == uMin)
+    return; // prevent divide-by-zero.  Jon Perry.  17 June 2002
+
+  if(mydu > uMax - uMin)
+    num_ulines = 2;
+  else
+    {
+      num_ulines = 3 + (Int) ((uMax-uMin)/mydu);
+    }
+  if(mydv>=vMax-vMin)
+    num_vlines = 2;
+  else
+    {
+      num_vlines = 2+(Int)((vMax-vMin)/mydv);
+    }
+
+  Int isRect = is_rect(loop);
+
+  if(isRect && (num_ulines<=2 || num_vlines<=2))
+    {
+      if(vlinear)
+	triangulateRect(loop, backend, 1, ulinear, vlinear);
+      else if(ulinear)
+	triangulateRect(loop, backend, -1, ulinear, vlinear);	
+      else
+	triangulateRect(loop, backend, 0, ulinear, vlinear);		
+    }
+
+   else if(isRect)
+    {
+      triangulateRectGen(loop, num_ulines-2, num_vlines-2, backend); 
+    }
+  else if( (num_ulines<=2 || num_vlines <=2) && ulinear)
+    {
+      monoTriangulationFunBackend(loop, compV2InY, &backend);
+    }
+  else if( (!ulinear) && (!vlinear) && (num_ulines == 2) && (num_vlines > 2))
+    {
+      monoTriangulationFunBackend(loop, compV2InY, &backend);
+    }
+  else 
+    {
+      directedLine* poly = arcLoopToDLineLoop(loop);
+
+      gridWrap grid(num_ulines, num_vlines, uMin, uMax, vMin, vMax);
+      primStream pStream(20, 20);
+      rectBlockArray rbArray(20);
+
+      sampleMonoPoly(poly, &grid, ulinear, vlinear, &pStream, &rbArray);
+
+      evalStream(&pStream);
+
+      evalRBArray(&rbArray, &grid);
+      
+#ifdef COUNT_TRIANGLES
+      num_triangles += pStream.num_triangles();
+      num_quads += rbArray.num_quads();
+#endif
+      poly->deleteSinglePolygonWithSline();      
+    }
+  
+#ifdef COUNT_TRIANGLES
+  printf("num_triangles=%i\n", num_triangles);
+  printf("num_quads = %i\n", num_quads);
+#endif
+}
+
+void Slicer::slice(Arc_ptr loop)
+{
+#ifdef USE_READ_FLAG
+  if(read_flag("flagFile"))
+    slice_new(loop);
+  else
+    slice_old(loop);
+
+#else
+    slice_new(loop);
+#endif
+
+}
+
+  
+
+Slicer::Slicer( Backend &b ) 
+	: CoveAndTiler( b ), Mesher( b ), backend( b )
+{
+    ulinear = 0;
+    vlinear = 0;
+}
+
+Slicer::~Slicer()
+{
+}
+
+void
+Slicer::setisolines( int x )
+{
+    isolines = x;
+}
+
+void
+Slicer::setstriptessellation( REAL x, REAL y )
+{
+    assert(x > 0 && y > 0);
+    du = x;
+    dv = y;
+    setDu( du );
+}
+
+void
+Slicer::slice_old( Arc_ptr loop )
+{
+    loop->markverts();
+
+    Arc_ptr extrema[4];
+    loop->getextrema( extrema );
+
+    unsigned int npts = loop->numpts();
+    TrimRegion::init( npts, extrema[0] );
+
+    Mesher::init( npts );
+
+    long ulines = uarray.init( du, extrema[1], extrema[3] );
+//printf("ulines = %i\n", ulines);
+    Varray varray;
+    long vlines = varray.init( dv, extrema[0], extrema[2] );
+//printf("vlines = %i\n", vlines);
+    long botv = 0;
+    long topv;
+    TrimRegion::init( varray.varray[botv] );
+    getGridExtent( &extrema[0]->pwlArc->pts[0], &extrema[0]->pwlArc->pts[0] );
+
+    for( long quad=0; quad<varray.numquads; quad++ ) {
+	backend.surfgrid( uarray.uarray[0], 
+		       uarray.uarray[ulines-1], 
+	 	       ulines-1, 
+		       varray.vval[quad], 
+		       varray.vval[quad+1], 
+		       varray.voffset[quad+1] - varray.voffset[quad] );
+
+	for( long i=varray.voffset[quad]+1; i <= varray.voffset[quad+1]; i++ ) {
+    	    topv = botv++;
+    	    advance( topv - varray.voffset[quad], 
+		     botv - varray.voffset[quad], 
+		     varray.varray[botv] );
+	    if( i == vlines )
+		getPts( extrema[2] );
+	    else
+		getPts( backend );
+	    getGridExtent();
+            if( isolines ) {
+	        outline();
+	    } else {
+		if( canTile() ) 
+		    coveAndTile();
+		else
+		    mesh();
+	    }
+        }
+   }
+}
+
+
+void
+Slicer::outline( void )
+{
+    GridTrimVertex upper, lower;
+    Hull::init( );
+
+    backend.bgnoutline();
+    while( (nextupper( &upper )) ) {
+	if( upper.isGridVert() )
+	    backend.linevert( upper.g );
+	else
+	    backend.linevert( upper.t );
+    }
+    backend.endoutline();
+
+    backend.bgnoutline();
+    while( (nextlower( &lower )) ) {
+	if( lower.isGridVert() )
+	    backend.linevert( lower.g );
+	else
+	    backend.linevert( lower.t );
+    }
+    backend.endoutline();
+}
+
+
+void
+Slicer::outline( Arc_ptr jarc )
+{
+    jarc->markverts();
+
+    if( jarc->pwlArc->npts >= 2 ) {
+	backend.bgnoutline();
+	for( int j = jarc->pwlArc->npts-1; j >= 0; j--  )
+	    backend.linevert( &(jarc->pwlArc->pts[j]) );
+	backend.endoutline();
+    }
+}
+
+