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diff --git a/mesalib/src/glu/sgi/libnurbs/internals/monoTriangulationBackend.cc b/mesalib/src/glu/sgi/libnurbs/internals/monoTriangulationBackend.cc
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+++ b/mesalib/src/glu/sgi/libnurbs/internals/monoTriangulationBackend.cc
@@ -0,0 +1,397 @@
+/*
+** 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.
+**
+*/
+/*
+*/
+
+#include "monoTriangulation.h"
+#include "polyUtil.h"
+#include "backend.h"
+#include "arc.h"
+
+void reflexChain::outputFan(Real v[2], Backend* backend)
+{
+ Int i;
+ /*
+ TrimVertex trimVert;
+ */
+ backend->bgntfan();
+
+ /*
+ trimVert.param[0]=v[0];
+ trimVert.param[1]=v[1];
+ backend->tmeshvert(&trimVert);
+ */
+ backend->tmeshvert(v[0], v[1]);
+
+ if(isIncreasing) {
+ for(i=0; i<index_queue; i++)
+ {
+ /*
+ trimVert.param[0]=queue[i][0];
+ trimVert.param[1]=queue[i][1];
+ backend->tmeshvert(&trimVert);
+ */
+ backend->tmeshvert(queue[i][0], queue[i][1]);
+ }
+ }
+ else {
+ for(i=index_queue-1; i>=0; i--)
+ {
+ /*
+ trimVert.param[0]=queue[i][0];
+ trimVert.param[1]=queue[i][1];
+ backend->tmeshvert(&trimVert);
+ */
+ backend->tmeshvert(queue[i][0], queue[i][1]);
+ }
+ }
+ backend->endtfan();
+}
+
+void reflexChain::processNewVertex(Real v[2], Backend* backend)
+{
+ Int i,j,k;
+ Int isReflex;
+ /*TrimVertex trimVert;*/
+ /*if there are at most one vertex in the queue, then simply insert
+ */
+ if(index_queue <=1){
+ insert(v);
+ return;
+ }
+
+ /*there are at least two vertices in the queue*/
+ j=index_queue-1;
+
+ for(i=j; i>=1; i--) {
+ if(isIncreasing) {
+ isReflex = (area(queue[i-1], queue[i], v) <= 0.0);
+ }
+ else /*decreasing*/{
+ isReflex = (area(v, queue[i], queue[i-1]) <= 0.0);
+ }
+ if(isReflex) {
+ break;
+ }
+ }
+
+ /*
+ *if i<j then vertices: i+1--j are convex
+ * output triangle fan:
+ * v, and queue[i], i+1, ..., j
+ */
+ if(i<j)
+ {
+ backend->bgntfan();
+ /*
+ trimVert.param[0]=v[0];
+ trimVert.param[1]=v[1];
+ backend->tmeshvert(& trimVert);
+ */
+ backend->tmeshvert(v[0], v[1]);
+
+ if(isIncreasing) {
+ for(k=i; k<=j; k++)
+ {
+ /*
+ trimVert.param[0]=queue[k][0];
+ trimVert.param[1]=queue[k][1];
+ backend->tmeshvert(& trimVert);
+ */
+ backend->tmeshvert(queue[k][0], queue[k][1]);
+ }
+ }
+ else {
+ for(k=j; k>=i; k--)
+ {
+ /*
+ trimVert.param[0]=queue[k][0];
+ trimVert.param[1]=queue[k][1];
+ backend->tmeshvert(& trimVert);
+ */
+ backend->tmeshvert(queue[k][0], queue[k][1]);
+ }
+ }
+
+ backend->endtfan();
+ }
+
+ /*delete vertices i+1--j from the queue*/
+ index_queue = i+1;
+ /*finally insert v at the end of the queue*/
+ insert(v);
+
+}
+
+
+void monoTriangulationRec(Real* topVertex, Real* botVertex,
+ vertexArray* inc_chain, Int inc_current,
+ vertexArray* dec_chain, Int dec_current,
+ Backend* backend)
+{
+ assert( inc_chain != NULL && dec_chain != NULL);
+ assert( ! (inc_current>=inc_chain->getNumElements() &&
+ dec_current>=dec_chain->getNumElements()));
+ Int inc_nVertices;
+ Int dec_nVertices;
+ Real** inc_array ;
+ Real** dec_array ;
+ Int i;
+ assert( ! ( (inc_chain==NULL) && (dec_chain==NULL)));
+
+ if(inc_current>=inc_chain->getNumElements()) /*no more vertices on inc_chain*/
+ {
+
+ dec_array = dec_chain->getArray();
+ dec_nVertices = dec_chain->getNumElements();
+ reflexChain rChain(20,0);
+ /*put the top vertex into the reflex chain*/
+ rChain.processNewVertex(topVertex, backend);
+ /*process all the vertices on the dec_chain*/
+ for(i=dec_current; i<dec_nVertices; i++){
+ rChain.processNewVertex(dec_array[i], backend);
+ }
+ /*process the bottom vertex*/
+ rChain.processNewVertex(botVertex, backend);
+
+ }
+ else if(dec_current>= dec_chain->getNumElements()) /*no more vertices on dec_chain*/
+ {
+ inc_array = inc_chain->getArray();
+ inc_nVertices= inc_chain->getNumElements();
+ reflexChain rChain(20,1);
+ /*put the top vertex into the reflex chain*/
+ rChain.processNewVertex(topVertex, backend);
+ /*process all the vertices on the inc_chain*/
+ for(i=inc_current; i<inc_nVertices; i++){
+ rChain.processNewVertex(inc_array[i], backend);
+ }
+ /*process the bottom vertex*/
+ rChain.processNewVertex(botVertex, backend);
+ }
+ else /*neither chain is empty*/
+ {
+ inc_array = inc_chain -> getArray();
+ dec_array = dec_chain -> getArray();
+ inc_nVertices= inc_chain->getNumElements();
+ dec_nVertices= dec_chain->getNumElements();
+ /*if top of inc_chain is 'lower' than top of dec_chain, process all the
+ *vertices on the dec_chain which are higher than top of inc_chain
+ */
+ if(compV2InY(inc_array[inc_current], dec_array[dec_current]) <= 0)
+ {
+
+ reflexChain rChain(20, 0);
+ rChain.processNewVertex(topVertex, backend);
+ for(i=dec_current; i<dec_nVertices; i++)
+ {
+ if(compV2InY(inc_array[inc_current], dec_array[i]) <= 0)
+ rChain.processNewVertex(dec_array[i], backend);
+ else
+ break;
+ }
+ rChain.outputFan(inc_array[inc_current], backend);
+ monoTriangulationRec(dec_array[i-1], botVertex,
+ inc_chain, inc_current,
+ dec_chain, i,
+ backend);
+ }
+ else /*compV2InY(inc_array[inc_current], dec_array[dec_current]) > 0*/
+ {
+
+ reflexChain rChain(20, 1);
+ rChain.processNewVertex(topVertex, backend);
+ for(i=inc_current; i<inc_nVertices; i++)
+ {
+ if(compV2InY(inc_array[i], dec_array[dec_current]) >0)
+ rChain.processNewVertex(inc_array[i], backend);
+ else
+ break;
+ }
+ rChain.outputFan(dec_array[dec_current], backend);
+ monoTriangulationRec(inc_array[i-1], botVertex,
+ inc_chain, i,
+ dec_chain, dec_current,
+ backend);
+ }
+ }/*end case neither is empty*/
+}
+
+
+void monoTriangulationFunBackend(Arc_ptr loop, Int (*compFun)(Real*, Real*), Backend* backend)
+{
+ Int i;
+ /*find the top vertex, bottom vertex, inccreasing chain, and decreasing chain,
+ *then call monoTriangulationRec
+ */
+ Arc_ptr tempV;
+ Arc_ptr topV;
+ Arc_ptr botV;
+ topV = botV = loop;
+ for(tempV = loop->next; tempV != loop; tempV = tempV->next)
+ {
+ if(compFun(topV->tail(), tempV->tail())<0) {
+ topV = tempV;
+ }
+ if(compFun(botV->tail(), tempV->tail())>0) {
+ botV = tempV;
+ }
+ }
+
+ /*creat increase and decrease chains*/
+ vertexArray inc_chain(20); /*this is a dynamic array*/
+ for(i=1; i<=topV->pwlArc->npts-2; i++) { /*the first vertex is the top vertex which doesn't belong to inc_chain*/
+ inc_chain.appendVertex(topV->pwlArc->pts[i].param);
+ }
+ for(tempV = topV->next; tempV != botV; tempV = tempV->next)
+ {
+ for(i=0; i<=tempV->pwlArc->npts-2; i++){
+ inc_chain.appendVertex(tempV->pwlArc->pts[i].param);
+ }
+ }
+
+ vertexArray dec_chain(20);
+ for(tempV = topV->prev; tempV != botV; tempV = tempV->prev)
+ {
+ for(i=tempV->pwlArc->npts-2; i>=0; i--){
+ dec_chain.appendVertex(tempV->pwlArc->pts[i].param);
+ }
+ }
+ for(i=botV->pwlArc->npts-2; i>=1; i--){
+ dec_chain.appendVertex(tempV->pwlArc->pts[i].param);
+ }
+
+ monoTriangulationRecFunBackend(topV->tail(), botV->tail(), &inc_chain, 0, &dec_chain, 0, compFun, backend);
+
+}
+
+/*if compFun == compV2InY, top to bottom: V-monotone
+ *if compFun == compV2InX, right to left: U-monotone
+ */
+void monoTriangulationRecFunBackend(Real* topVertex, Real* botVertex,
+ vertexArray* inc_chain, Int inc_current,
+ vertexArray* dec_chain, Int dec_current,
+ Int (*compFun)(Real*, Real*),
+ Backend* backend)
+{
+ assert( inc_chain != NULL && dec_chain != NULL);
+ assert( ! (inc_current>=inc_chain->getNumElements() &&
+ dec_current>=dec_chain->getNumElements()));
+ Int inc_nVertices;
+ Int dec_nVertices;
+ Real** inc_array ;
+ Real** dec_array ;
+ Int i;
+ assert( ! ( (inc_chain==NULL) && (dec_chain==NULL)));
+
+ if(inc_current>=inc_chain->getNumElements()) /*no more vertices on inc_chain*/
+ {
+
+ dec_array = dec_chain->getArray();
+ dec_nVertices = dec_chain->getNumElements();
+ reflexChain rChain(20,0);
+ /*put the top vertex into the reflex chain*/
+ rChain.processNewVertex(topVertex, backend);
+ /*process all the vertices on the dec_chain*/
+ for(i=dec_current; i<dec_nVertices; i++){
+ rChain.processNewVertex(dec_array[i], backend);
+ }
+ /*process the bottom vertex*/
+ rChain.processNewVertex(botVertex, backend);
+
+ }
+ else if(dec_current>= dec_chain->getNumElements()) /*no more vertices on dec_chain*/
+ {
+ inc_array = inc_chain->getArray();
+ inc_nVertices= inc_chain->getNumElements();
+ reflexChain rChain(20,1);
+ /*put the top vertex into the reflex chain*/
+ rChain.processNewVertex(topVertex, backend);
+ /*process all the vertices on the inc_chain*/
+ for(i=inc_current; i<inc_nVertices; i++){
+ rChain.processNewVertex(inc_array[i], backend);
+ }
+ /*process the bottom vertex*/
+ rChain.processNewVertex(botVertex, backend);
+ }
+ else /*neither chain is empty*/
+ {
+ inc_array = inc_chain -> getArray();
+ dec_array = dec_chain -> getArray();
+ inc_nVertices= inc_chain->getNumElements();
+ dec_nVertices= dec_chain->getNumElements();
+ /*if top of inc_chain is 'lower' than top of dec_chain, process all the
+ *vertices on the dec_chain which are higher than top of inc_chain
+ */
+ if(compFun(inc_array[inc_current], dec_array[dec_current]) <= 0)
+ {
+
+ reflexChain rChain(20, 0);
+ rChain.processNewVertex(topVertex, backend);
+ for(i=dec_current; i<dec_nVertices; i++)
+ {
+ if(compFun(inc_array[inc_current], dec_array[i]) <= 0)
+ rChain.processNewVertex(dec_array[i], backend);
+ else
+ break;
+ }
+ rChain.outputFan(inc_array[inc_current], backend);
+ monoTriangulationRecFunBackend(dec_array[i-1], botVertex,
+ inc_chain, inc_current,
+ dec_chain, i,
+ compFun,
+ backend);
+ }
+ else /*compFun(inc_array[inc_current], dec_array[dec_current]) > 0*/
+ {
+
+ reflexChain rChain(20, 1);
+ rChain.processNewVertex(topVertex, backend);
+ for(i=inc_current; i<inc_nVertices; i++)
+ {
+ if(compFun(inc_array[i], dec_array[dec_current]) >0)
+ rChain.processNewVertex(inc_array[i], backend);
+ else
+ break;
+ }
+ rChain.outputFan(dec_array[dec_current], backend);
+ monoTriangulationRecFunBackend(inc_array[i-1], botVertex,
+ inc_chain, i,
+ dec_chain, dec_current,
+ compFun,
+ backend);
+ }
+ }/*end case neither is empty*/
+}
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