/* $Id: nurbs.c,v 1.2 1999/11/11 03:21:43 kendallb Exp $ */

/*
 * Mesa 3-D graphics library
 * Version:  3.1
 * Copyright (C) 1995-1999  Brian Paul
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


/*
 * $Log: nurbs.c,v $
 * Revision 1.2  1999/11/11 03:21:43  kendallb
 *
 *  . Updated GL/gl.h with GLCALLACKP and GLAPIENTRYP macros for compatibility
 *    with the IBM VisualAge C++ compiler. Eventually some more code will be
 *    needed in the headers to enable the reversal of (__stdcall*) to (*__stdcall)
 *    for the IBM compilers, however we currently build using our own header files
 *    that already handle this.
 *
 *  . Changed instances of (GLCALLBACK*) to GLCALLBACKP for compatibility
 *    with the IBM VisualAge C++ compiler in src-glu.
 *
 *  . Misc cleanups for warnings generated with Watcom C++ in src-glu. Compiles
 *    with 0 warnings now.
 *
 *  . tess_hash.c: line 244 - Why is this function stubbed out? I removed the
 *    code with a #if 0 to avoid a compiler warning, but it looks dangerous.
 *
 * Revision 1.1.1.1  1999/08/19 00:55:42  jtg
 * Imported sources
 *
 * Revision 1.14  1999/01/03 03:23:15  brianp
 * now using GLAPIENTRY and GLCALLBACK keywords (Ted Jump)
 *
 * Revision 1.13  1998/06/01 01:07:49  brianp
 * small update for Next/OpenStep from Alexander Mai
 *
 * Revision 1.12  1998/03/15 18:14:30  brianp
 * fixed a compiler cast warning
 *
 * Revision 1.11  1998/02/07 14:29:11  brianp
 * fixed casting problem in gluNurbsCallback, again
 *
 * Revision 1.10  1998/02/04 00:21:20  brianp
 * fixed cygnus compilation problem (Stephane Rehel)
 *
 * Revision 1.9  1998/01/16 03:35:26  brianp
 * fixed Windows compilation warnings (Theodore Jump)
 *
 * Revision 1.8  1997/09/17 01:51:48  brianp
 * changed glu*Callback() functions to match prototype in glu.h
 *
 * Revision 1.7  1997/07/24 01:28:44  brianp
 * changed precompiled header symbol from PCH to PC_HEADER
 *
 * Revision 1.6  1997/07/24 01:26:31  brianp
 * added CALLBACK keyword to gluNurbsCallback()
 *
 * Revision 1.5  1997/05/28 02:29:38  brianp
 * added support for precompiled headers (PCH), inserted APIENTRY keyword
 *
 * Revision 1.4  1997/05/27 03:17:22  brianp
 * minor clean-up
 *
 * Revision 1.3  1997/05/27 03:00:16  brianp
 * incorporated Bogdan's new NURBS code
 *
 * Revision 1.2  1996/09/27 23:11:23  brianp
 * ifdef'd out unimplemented trimmed nurbs code
 *
 * Revision 1.1  1996/09/27 01:19:39  brianp
 * Initial revision
 *
 */


/*
 * NURBS implementation written by Bogdan Sikorski (bogdan@cira.it)
 * See README2 for more info.
 */

#ifdef PC_HEADER
#include "all.h"
#else
#include <stdio.h>
#include <stdlib.h>
#include "gluP.h"
#include "nurbs.h"
#endif


void
call_user_error( GLUnurbsObj *nobj, GLenum error )
{
    nobj->error=error;
    if(nobj->error_callback != NULL) {
        (*(nobj->error_callback))(error);
    }
    else {
       printf("NURBS error %d %s\n", error, (char *) gluErrorString(error) );
    }
}



GLUnurbsObj * GLAPIENTRY gluNewNurbsRenderer( void )
{
   GLUnurbsObj *n;
   GLfloat tmp_viewport[4];
   GLint i,j;

   n = (GLUnurbsObj *) malloc( sizeof(GLUnurbsObj) );
   if (n) {
      /* init */
      n->culling=GL_FALSE;
      n->nurbs_type=GLU_NURBS_NONE;
      n->error=GLU_NO_ERROR;
      n->error_callback=NULL;
      n->auto_load_matrix=GL_TRUE;
      n->sampling_tolerance=50.0;
      n->parametric_tolerance=0.5;
      n->u_step = n->v_step = 100;
      n->sampling_method = GLU_PATH_LENGTH;
      n->display_mode=GLU_FILL;
      /* in case the user doesn't supply the sampling matrices */
      /* set projection and modelview to identity */
      for(i=0;i<4;i++)
          for(j=0;j<4;j++)
              if(i==j)
              {
                n->sampling_matrices.model[i*4+j]=1.0;
                n->sampling_matrices.proj[i*4+j]=1.0;
            }
            else
              {
                n->sampling_matrices.model[i*4+j]=0.0;
                n->sampling_matrices.proj[i*4+j]=0.0;
            }
      /* and set the viewport sampling matrix to current ciewport */
      glGetFloatv(GL_VIEWPORT,tmp_viewport);
      for(i=0;i<4;i++)
          n->sampling_matrices.viewport[i]=tmp_viewport[i];
      n->trim=NULL;
   }
   return n;
}



void GLAPIENTRY gluDeleteNurbsRenderer( GLUnurbsObj *nobj )
{
   if (nobj) {
      free( nobj );
   }
}



void GLAPIENTRY gluLoadSamplingMatrices( GLUnurbsObj *nobj,
                  const GLfloat modelMatrix[16],
                  const GLfloat projMatrix[16],
                  const GLint viewport[4] )
{
    GLint    i;

    for(i=0;i<16;i++)
    {
        nobj->sampling_matrices.model[i]=modelMatrix[i];
        nobj->sampling_matrices.proj[i]=projMatrix[i];
    }
    for(i=0;i<4;i++)
        nobj->sampling_matrices.viewport[i]=viewport[i];
}


void GLAPIENTRY gluNurbsProperty( GLUnurbsObj *nobj, GLenum property, GLfloat value )
{
   GLenum val;

   switch (property) {
      case GLU_SAMPLING_TOLERANCE:
           if(value <= 0.0)
           {
               call_user_error(nobj,GLU_INVALID_VALUE);
               return;
         }
         nobj->sampling_tolerance=value;
         break;
      case GLU_PARAMETRIC_TOLERANCE:
           if(value <= 0.0)
           {
               call_user_error(nobj,GLU_INVALID_VALUE);
               return;
         }
         nobj->parametric_tolerance=value;
         break;
      case GLU_U_STEP:
           if(value <= 0.0)
           {
               call_user_error(nobj,GLU_INVALID_VALUE);
               return;
         }
         nobj->u_step=(GLint)value;
         break;
      case GLU_V_STEP:
           if(value <= 0.0)
           {
               call_user_error(nobj,GLU_INVALID_VALUE);
               return;
         }
         nobj->v_step=(GLint)value;
         break;
      case GLU_SAMPLING_METHOD:
		 val = (GLenum)value;
         if(val!=GLU_PATH_LENGTH && val!=GLU_PARAMETRIC_ERROR && val!=GLU_DOMAIN_DISTANCE)
         {
             call_user_error(nobj,GLU_INVALID_ENUM);
             return;
         }
		 nobj->sampling_method=val;
         break;
      case GLU_DISPLAY_MODE:
         val=(GLenum)value;
         if(val!=GLU_FILL && val!=GLU_OUTLINE_POLYGON && val!=GLU_OUTLINE_PATCH)
         {
             call_user_error(nobj,GLU_INVALID_ENUM);
             return;
         }
         if(nobj->nurbs_type==GLU_NURBS_CURVE)
         {
             call_user_error(nobj,GLU_NURBS_ERROR26);
             return;
         }
         nobj->display_mode=val;
if(val==GLU_OUTLINE_PATCH)
    fprintf(stderr,"NURBS, for the moment, can display only in POLYGON mode\n");
         break;
      case GLU_CULLING:
         val=(GLenum)value;
         if(val!=GL_TRUE && val!=GL_FALSE)
         {
             call_user_error(nobj,GLU_INVALID_ENUM);
             return;
         }
         nobj->culling = (GLboolean) value;
         break;
      case GLU_AUTO_LOAD_MATRIX:
         val=(GLenum)value;
         if(val!=GL_TRUE && val!=GL_FALSE)
         {
             call_user_error(nobj,GLU_INVALID_ENUM);
             return;
         }
         nobj->auto_load_matrix = (GLboolean) value;
         break;
      default:
         call_user_error(nobj,GLU_NURBS_ERROR26);
   }
}


void GLAPIENTRY gluGetNurbsProperty( GLUnurbsObj *nobj, GLenum property, GLfloat *value )
{
   switch (property) {
      case GLU_SAMPLING_TOLERANCE:
         *value = nobj->sampling_tolerance;
         break;
      case GLU_DISPLAY_MODE:
         *value = (GLfloat) (GLint) nobj->display_mode;
         break;
      case GLU_CULLING:
         *value = nobj->culling ? 1.0 : 0.0;
         break;
      case GLU_AUTO_LOAD_MATRIX:
         *value = nobj->auto_load_matrix ? 1.0 : 0.0;
         break;
      default:
         call_user_error(nobj,GLU_INVALID_ENUM);
   }
}



void GLAPIENTRY gluBeginCurve( GLUnurbsObj *nobj )
{
    if(nobj->nurbs_type==GLU_NURBS_CURVE)
    {
        call_user_error(nobj,GLU_NURBS_ERROR6);
        return;
    }
    nobj->nurbs_type=GLU_NURBS_CURVE;
    nobj->curve.geom.type=GLU_INVALID_ENUM;
    nobj->curve.color.type=GLU_INVALID_ENUM;
    nobj->curve.texture.type=GLU_INVALID_ENUM;
    nobj->curve.normal.type=GLU_INVALID_ENUM;
}


void GLAPIENTRY gluEndCurve( GLUnurbsObj * nobj )
{
    if(nobj->nurbs_type==GLU_NURBS_NONE)
    {
        call_user_error(nobj,GLU_NURBS_ERROR7);
        return;
    }
    if(nobj->curve.geom.type==GLU_INVALID_ENUM)
    {
        call_user_error(nobj,GLU_NURBS_ERROR8);
        nobj->nurbs_type=GLU_NURBS_NONE;
        return;
    }
    glPushAttrib( (GLbitfield) (GL_EVAL_BIT | GL_ENABLE_BIT) );
    glDisable(GL_MAP1_VERTEX_3);
    glDisable(GL_MAP1_VERTEX_4);
    glDisable(GL_MAP1_INDEX);
    glDisable(GL_MAP1_COLOR_4);
    glDisable(GL_MAP1_NORMAL);
    glDisable(GL_MAP1_TEXTURE_COORD_1);
    glDisable(GL_MAP1_TEXTURE_COORD_2);
    glDisable(GL_MAP1_TEXTURE_COORD_3);
    glDisable(GL_MAP1_TEXTURE_COORD_4);
    glDisable(GL_MAP2_VERTEX_3);
    glDisable(GL_MAP2_VERTEX_4);
    glDisable(GL_MAP2_INDEX);
    glDisable(GL_MAP2_COLOR_4);
    glDisable(GL_MAP2_NORMAL);
    glDisable(GL_MAP2_TEXTURE_COORD_1);
    glDisable(GL_MAP2_TEXTURE_COORD_2);
    glDisable(GL_MAP2_TEXTURE_COORD_3);
    glDisable(GL_MAP2_TEXTURE_COORD_4);
    do_nurbs_curve(nobj);
    glPopAttrib();
    nobj->nurbs_type=GLU_NURBS_NONE;
}


void GLAPIENTRY gluNurbsCurve( GLUnurbsObj *nobj, GLint nknots, GLfloat *knot,
            GLint stride, GLfloat *ctlarray, GLint order, GLenum type )
{
    if(nobj->nurbs_type==GLU_NURBS_TRIM)
    {
#if 0
/* TODO: NOT IMPLEMENTED YET */
        nurbs_trim *ptr1;
        trim_list *ptr2;

        if(type!=GLU_MAP1_TRIM_2 && type!=GLU_MAP1_TRIM_3)
        {
            call_user_error(nobj,GLU_NURBS_ERROR14);
            return;
        }
        for(ptr1=nobj->trim;ptr1->next;ptr1=ptr1->next);
        if(ptr1->trim_loop)
        {
            for(ptr2=ptr1->trim_loop;ptr2->next;ptr2=ptr2->next);
            if((ptr2->next=(trim_list *)malloc(sizeof(trim_list)))==NULL)
            {
                call_user_error(nobj,GLU_OUT_OF_MEMORY);
                return;
            }
            ptr2=ptr2->next;
        }
        else
        {
            if((ptr2=(trim_list *)malloc(sizeof(trim_list)))==NULL)
            {
                call_user_error(nobj,GLU_OUT_OF_MEMORY);
                return;
            }
            ptr1->trim_loop=ptr2;
        }
        ptr2->trim_type=GLU_TRIM_NURBS;
        ptr2->curve.nurbs_curve.knot_count=nknots;
        ptr2->curve.nurbs_curve.knot=knot;
        ptr2->curve.nurbs_curve.stride=stride;
        ptr2->curve.nurbs_curve.ctrlarray=ctlarray;
        ptr2->curve.nurbs_curve.order=order;
        ptr2->curve.nurbs_curve.dim= (type==GLU_MAP1_TRIM_2 ? 2 : 3 );
        ptr2->curve.nurbs_curve.type=type;
        ptr2->next=NULL;
#endif
    }
    else
    {
        if(type==GLU_MAP1_TRIM_2 || type==GLU_MAP1_TRIM_3)
        {
            call_user_error(nobj,GLU_NURBS_ERROR22);
            return;
        }
        if(nobj->nurbs_type!=GLU_NURBS_CURVE)
        {
            call_user_error(nobj,GLU_NURBS_ERROR10);
            return;
        }
        switch(type)
        {
            case GL_MAP1_VERTEX_3:
            case GL_MAP1_VERTEX_4:
                if(nobj->curve.geom.type!=GLU_INVALID_ENUM)
                {
                    call_user_error(nobj,GLU_NURBS_ERROR8);
                    return;
                }
                nobj->curve.geom.type=type;
                nobj->curve.geom.knot_count=nknots;
                nobj->curve.geom.knot=knot;
                nobj->curve.geom.stride=stride;
                nobj->curve.geom.ctrlarray=ctlarray;
                nobj->curve.geom.order=order;
                break;
            case GL_MAP1_INDEX:
            case GL_MAP1_COLOR_4:
                nobj->curve.color.type=type;
                nobj->curve.color.knot_count=nknots;
                nobj->curve.color.knot=knot;
                nobj->curve.color.stride=stride;
                nobj->curve.color.ctrlarray=ctlarray;
                nobj->curve.color.order=order;
                break;
            case GL_MAP1_NORMAL:
                nobj->curve.normal.type=type;
                nobj->curve.normal.knot_count=nknots;
                nobj->curve.normal.knot=knot;
                nobj->curve.normal.stride=stride;
                nobj->curve.normal.ctrlarray=ctlarray;
                nobj->curve.normal.order=order;
                break;
            case GL_MAP1_TEXTURE_COORD_1:
            case GL_MAP1_TEXTURE_COORD_2:
            case GL_MAP1_TEXTURE_COORD_3:
            case GL_MAP1_TEXTURE_COORD_4:
                nobj->curve.texture.type=type;
                nobj->curve.texture.knot_count=nknots;
                nobj->curve.texture.knot=knot;
                nobj->curve.texture.stride=stride;
                nobj->curve.texture.ctrlarray=ctlarray;
                nobj->curve.texture.order=order;
                break;
            default:
                 call_user_error(nobj,GLU_INVALID_ENUM);
        }
    }
}


void GLAPIENTRY gluBeginSurface( GLUnurbsObj *nobj )
{
    switch(nobj->nurbs_type)
    {
        case GLU_NURBS_NONE:
            nobj->nurbs_type=GLU_NURBS_SURFACE;
            nobj->surface.geom.type=GLU_INVALID_ENUM;
            nobj->surface.color.type=GLU_INVALID_ENUM;
            nobj->surface.texture.type=GLU_INVALID_ENUM;
            nobj->surface.normal.type=GLU_INVALID_ENUM;
            break;
        case GLU_NURBS_TRIM:
            call_user_error(nobj,GLU_NURBS_ERROR16);
            break;
        case GLU_NURBS_SURFACE:
        case GLU_NURBS_NO_TRIM:
        case GLU_NURBS_TRIM_DONE:
            call_user_error(nobj,GLU_NURBS_ERROR27);
            break;
        case GLU_NURBS_CURVE:
            call_user_error(nobj,GLU_NURBS_ERROR6);
            break;
    }
}


void GLAPIENTRY gluEndSurface( GLUnurbsObj * nobj )
{
    switch(nobj->nurbs_type)
    {
        case GLU_NURBS_NONE:
            call_user_error(nobj,GLU_NURBS_ERROR13);
            break;
        case GLU_NURBS_TRIM:
            call_user_error(nobj,GLU_NURBS_ERROR12);
            break;
        case GLU_NURBS_TRIM_DONE:
/*            if(nobj->trim->trim_loop==NULL)
            {
                call_user_error(nobj,GLU_NURBS_ERROR18);
                return;
            }*/
            /* no break - fallthrough */
        case GLU_NURBS_NO_TRIM:
            glPushAttrib( (GLbitfield)
				(GL_EVAL_BIT | GL_ENABLE_BIT | GL_POLYGON_BIT) );
            glDisable(GL_MAP2_VERTEX_3);
            glDisable(GL_MAP2_VERTEX_4);
            glDisable(GL_MAP2_INDEX);
            glDisable(GL_MAP2_COLOR_4);
            glDisable(GL_MAP2_NORMAL);
            glDisable(GL_MAP2_TEXTURE_COORD_1);
            glDisable(GL_MAP2_TEXTURE_COORD_2);
            glDisable(GL_MAP2_TEXTURE_COORD_3);
            glDisable(GL_MAP2_TEXTURE_COORD_4);
/*            glDisable(GL_MAP1_VERTEX_3);
            glDisable(GL_MAP1_VERTEX_4);
            glDisable(GL_MAP1_INDEX);
            glDisable(GL_MAP1_COLOR_4);
            glDisable(GL_MAP1_NORMAL);
            glDisable(GL_MAP1_TEXTURE_COORD_1);
            glDisable(GL_MAP1_TEXTURE_COORD_2);
            glDisable(GL_MAP1_TEXTURE_COORD_3);
            glDisable(GL_MAP1_TEXTURE_COORD_4);*/
            do_nurbs_surface(nobj);
            glPopAttrib();
            break;
        default:
            call_user_error(nobj,GLU_NURBS_ERROR8);
    }
    nobj->nurbs_type=GLU_NURBS_NONE;
}


void GLAPIENTRY gluNurbsSurface( GLUnurbsObj *nobj,
              GLint sknot_count, GLfloat *sknot,
              GLint tknot_count, GLfloat *tknot,
              GLint s_stride, GLint t_stride,
              GLfloat *ctrlarray,
              GLint sorder, GLint torder,
              GLenum type )
{
    if(nobj->nurbs_type==GLU_NURBS_NO_TRIM || nobj->nurbs_type==GLU_NURBS_TRIM ||
        nobj->nurbs_type==GLU_NURBS_TRIM_DONE)
    {
        if(type==GL_MAP2_VERTEX_3 || type==GL_MAP2_VERTEX_4)
        {
            call_user_error(nobj,GLU_NURBS_ERROR8);
            return;
        }
    }
    else
    if(nobj->nurbs_type!=GLU_NURBS_SURFACE)
    {
        call_user_error(nobj,GLU_NURBS_ERROR11);
        return;
    }
    switch(type)
    {
        case GL_MAP2_VERTEX_3:
        case GL_MAP2_VERTEX_4:
            nobj->surface.geom.sknot_count=sknot_count;
            nobj->surface.geom.sknot=sknot;
            nobj->surface.geom.tknot_count=tknot_count;
            nobj->surface.geom.tknot=tknot;
            nobj->surface.geom.s_stride=s_stride;
            nobj->surface.geom.t_stride=t_stride;
            nobj->surface.geom.ctrlarray=ctrlarray;
            nobj->surface.geom.sorder=sorder;
            nobj->surface.geom.torder=torder;
            nobj->surface.geom.type=type;
            nobj->nurbs_type=GLU_NURBS_NO_TRIM;
            break;
        case GL_MAP2_INDEX:
        case GL_MAP2_COLOR_4:
            nobj->surface.color.sknot_count=sknot_count;
            nobj->surface.color.sknot=sknot;
            nobj->surface.color.tknot_count=tknot_count;
            nobj->surface.color.tknot=tknot;
            nobj->surface.color.s_stride=s_stride;
            nobj->surface.color.t_stride=t_stride;
            nobj->surface.color.ctrlarray=ctrlarray;
            nobj->surface.color.sorder=sorder;
            nobj->surface.color.torder=torder;
            nobj->surface.color.type=type;
            break;
        case GL_MAP2_NORMAL:
            nobj->surface.normal.sknot_count=sknot_count;
            nobj->surface.normal.sknot=sknot;
            nobj->surface.normal.tknot_count=tknot_count;
            nobj->surface.normal.tknot=tknot;
            nobj->surface.normal.s_stride=s_stride;
            nobj->surface.normal.t_stride=t_stride;
            nobj->surface.normal.ctrlarray=ctrlarray;
            nobj->surface.normal.sorder=sorder;
            nobj->surface.normal.torder=torder;
            nobj->surface.normal.type=type;
            break;
        case GL_MAP2_TEXTURE_COORD_1:
        case GL_MAP2_TEXTURE_COORD_2:
        case GL_MAP2_TEXTURE_COORD_3:
        case GL_MAP2_TEXTURE_COORD_4:
            nobj->surface.texture.sknot_count=sknot_count;
            nobj->surface.texture.sknot=sknot;
            nobj->surface.texture.tknot_count=tknot_count;
            nobj->surface.texture.tknot=tknot;
            nobj->surface.texture.s_stride=s_stride;
            nobj->surface.texture.t_stride=t_stride;
            nobj->surface.texture.ctrlarray=ctrlarray;
            nobj->surface.texture.sorder=sorder;
            nobj->surface.texture.torder=torder;
            nobj->surface.texture.type=type;
            break;
        default:
             call_user_error(nobj,GLU_INVALID_ENUM);
    }
}


void GLAPIENTRY
gluNurbsCallback( GLUnurbsObj *nobj, GLenum which, void (GLCALLBACKP fn)())
{
#if defined(__CYGWIN32__) || defined(OPENSTEP)
    nobj->error_callback = (void(*)(GLenum))fn;
#else
	nobj->error_callback = (void(GLCALLBACKP)(GLenum))fn;
#endif

    if(which!=GLU_ERROR)
        call_user_error(nobj,GLU_INVALID_ENUM);
}

void GLAPIENTRY
gluBeginTrim( GLUnurbsObj *nobj )
{
#if 0
    nurbs_trim *ptr;
#endif

    if(nobj->nurbs_type!=GLU_NURBS_TRIM_DONE)
        if(nobj->nurbs_type!=GLU_NURBS_NO_TRIM)
        {
            call_user_error(nobj,GLU_NURBS_ERROR15);
            return;
        }
    nobj->nurbs_type=GLU_NURBS_TRIM;
fprintf(stderr,"NURBS - trimming not supported yet\n");
#if 0
    if((ptr=(nurbs_trim *)malloc(sizeof(nurbs_trim)))==NULL)
    {
        call_user_error(nobj,GLU_OUT_OF_MEMORY);
        return;
    }
    if(nobj->trim)
    {
        nurbs_trim *tmp_ptr;

        for(tmp_ptr=nobj->trim;tmp_ptr->next;tmp_ptr=tmp_ptr->next);
        tmp_ptr->next=ptr;
    }
    else
        nobj->trim=ptr;
    ptr->trim_loop=NULL;
    ptr->segments=NULL;
    ptr->next=NULL;
#endif
}

void GLAPIENTRY
gluPwlCurve( GLUnurbsObj *nobj, GLint count, GLfloat *array, GLint stride,
    GLenum type)
{
#if 0
    nurbs_trim *ptr1;
    trim_list *ptr2;
#endif
    if(nobj->nurbs_type==GLU_NURBS_CURVE)
    {
        call_user_error(nobj,GLU_NURBS_ERROR9);
        return;
    }
    if(nobj->nurbs_type==GLU_NURBS_NONE)
    {
        call_user_error(nobj,GLU_NURBS_ERROR19);
        return;
    }
    if(type!=GLU_MAP1_TRIM_2 && type!=GLU_MAP1_TRIM_3)
    {
        call_user_error(nobj,GLU_NURBS_ERROR14);
        return;
    }
#if 0
    for(ptr1=nobj->trim;ptr1->next;ptr1=ptr1->next);
    if(ptr1->trim_loop)
    {
        for(ptr2=ptr1->trim_loop;ptr2->next;ptr2=ptr2->next);
        if((ptr2->next=(trim_list *)malloc(sizeof(trim_list)))==NULL)
        {
            call_user_error(nobj,GLU_OUT_OF_MEMORY);
            return;
        }
        ptr2=ptr2->next;
    }
    else
    {
        if((ptr2=(trim_list *)malloc(sizeof(trim_list)))==NULL)
        {
            call_user_error(nobj,GLU_OUT_OF_MEMORY);
            return;
        }
        ptr1->trim_loop=ptr2;
    }
    ptr2->trim_type=GLU_TRIM_PWL;
    ptr2->curve.pwl_curve.pt_count=count;
    ptr2->curve.pwl_curve.ctrlarray=array;
    ptr2->curve.pwl_curve.stride=stride;
    ptr2->curve.pwl_curve.dim= (type==GLU_MAP1_TRIM_2 ? 2 : 3 );
    ptr2->curve.pwl_curve.type=type;
    ptr2->next=NULL;
#endif
}

void GLAPIENTRY
gluEndTrim( GLUnurbsObj *nobj )
{
    if(nobj->nurbs_type!=GLU_NURBS_TRIM)
    {
        call_user_error(nobj,GLU_NURBS_ERROR17);
        return;
    }
    nobj->nurbs_type=GLU_NURBS_TRIM_DONE;
}