summaryrefslogtreecommitdiff
path: root/src/glu/mesa/nurbsutl.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/glu/mesa/nurbsutl.c')
-rw-r--r--src/glu/mesa/nurbsutl.c1403
1 files changed, 1403 insertions, 0 deletions
diff --git a/src/glu/mesa/nurbsutl.c b/src/glu/mesa/nurbsutl.c
new file mode 100644
index 0000000000..f0f166cb64
--- /dev/null
+++ b/src/glu/mesa/nurbsutl.c
@@ -0,0 +1,1403 @@
+/* $Id: nurbsutl.c,v 1.1 1999/08/19 00:55:42 jtg Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 2.4
+ * Copyright (C) 1995-1997 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: nurbsutl.c,v $
+ * Revision 1.1 1999/08/19 00:55:42 jtg
+ * Initial revision
+ *
+ * Revision 1.8 1999/06/08 00:44:51 brianp
+ * OpenStep updates (pete@ohm.york.ac.uk)
+ *
+ * Revision 1.7 1998/07/26 02:07:59 brianp
+ * updated for Windows compilation per Ted Jump
+ *
+ * Revision 1.6 1997/10/29 02:02:20 brianp
+ * various MS Windows compiler changes (David Bucciarelli, v20 3dfx driver)
+ *
+ * Revision 1.5 1997/07/24 01:28:44 brianp
+ * changed precompiled header symbol from PCH to PC_HEADER
+ *
+ * Revision 1.4 1997/05/28 02:29:38 brianp
+ * added support for precompiled headers (PCH), inserted APIENTRY keyword
+ *
+ * Revision 1.3 1997/05/27 03:19:54 brianp
+ * minor clean-up
+ *
+ * Revision 1.2 1997/05/27 03:00:16 brianp
+ * incorporated Bogdan's new 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 <math.h>
+#include <stdlib.h>
+#include "gluP.h"
+#include "nurbs.h"
+#endif
+
+
+GLenum
+test_knot(GLint nknots, GLfloat *knot, GLint order)
+{
+ GLsizei i;
+ GLint knot_mult;
+ GLfloat tmp_knot;
+
+ tmp_knot=knot[0];
+ knot_mult=1;
+ for(i=1;i<nknots;i++)
+ {
+ if(knot[i] < tmp_knot)
+ return GLU_NURBS_ERROR4;
+ if(fabs(tmp_knot-knot[i]) > EPSILON)
+ {
+ if(knot_mult>order)
+ return GLU_NURBS_ERROR5;
+ knot_mult=1;
+ tmp_knot=knot[i];
+ }
+ else
+ ++knot_mult;
+ }
+ return GLU_NO_ERROR;
+}
+
+static int
+/* qsort function */
+#if defined(WIN32) && !defined(OPENSTEP)
+__cdecl
+#endif
+knot_sort(const void *a, const void *b)
+{
+ GLfloat x,y;
+
+ x=*((GLfloat *)a);
+ y=*((GLfloat *)b);
+ if(fabs(x-y) < EPSILON)
+ return 0;
+ if(x > y)
+ return 1;
+ return -1;
+}
+
+/* insert into dest knot all values within the valid range from src knot */
+/* that do not appear in dest */
+void
+collect_unified_knot(knot_str_type *dest, knot_str_type *src,
+ GLfloat maximal_min_knot, GLfloat minimal_max_knot)
+{
+ GLfloat *src_knot,*dest_knot;
+ GLint src_t_min,src_t_max,dest_t_min,dest_t_max;
+ GLint src_nknots,dest_nknots;
+ GLint i,j,k,new_cnt;
+ GLboolean not_found_flag;
+
+ src_knot=src->unified_knot;
+ dest_knot=dest->unified_knot;
+ src_t_min=src->t_min;
+ src_t_max=src->t_max;
+ dest_t_min=dest->t_min;
+ dest_t_max=dest->t_max;
+ src_nknots=src->unified_nknots;
+ dest_nknots=dest->unified_nknots;
+
+ k=new_cnt=dest_nknots;
+ for(i=src_t_min;i<=src_t_max;i++)
+ if(src_knot[i] - maximal_min_knot > -EPSILON &&
+ src_knot[i] - minimal_max_knot < EPSILON)
+ {
+ not_found_flag=GL_TRUE;
+ for(j=dest_t_min;j<=dest_t_max;j++)
+ if(fabs(dest_knot[j]-src_knot[i]) < EPSILON)
+ {
+ not_found_flag=GL_FALSE;
+ break;
+ }
+ if(not_found_flag)
+ {
+ /* knot from src is not in dest - add this knot to dest */
+ dest_knot[k++]=src_knot[i];
+ ++new_cnt;
+ ++(dest->t_max); /* the valid range widens */
+ ++(dest->delta_nknots); /* increment the extra knot value counter */
+ }
+ }
+ dest->unified_nknots=new_cnt;
+ qsort((void *)dest_knot,(size_t)new_cnt,(size_t)sizeof(GLfloat),
+ &knot_sort);
+}
+
+/* basing on the new common knot range for all attributes set */
+/* t_min and t_max values for each knot - they will be used later on */
+/* by explode_knot() and calc_new_ctrl_pts */
+static void
+set_new_t_min_t_max(knot_str_type *geom_knot, knot_str_type *color_knot,
+ knot_str_type *normal_knot, knot_str_type *texture_knot,
+ GLfloat maximal_min_knot, GLfloat minimal_max_knot)
+{
+ GLuint t_min,t_max,cnt;
+
+ if(minimal_max_knot-maximal_min_knot < EPSILON)
+ {
+ /* knot common range empty */
+ geom_knot->t_min=geom_knot->t_max=0;
+ color_knot->t_min=color_knot->t_max=0;
+ normal_knot->t_min=normal_knot->t_max=0;
+ texture_knot->t_min=texture_knot->t_max=0;
+ }
+ else
+ {
+ if(geom_knot->unified_knot!=NULL)
+ {
+ cnt=geom_knot->unified_nknots;
+ for(t_min=0;t_min<cnt;t_min++)
+ if(fabs((geom_knot->unified_knot)[t_min] - maximal_min_knot) <
+ EPSILON)
+ break;
+ for(t_max=cnt-1;t_max;t_max--)
+ if(fabs((geom_knot->unified_knot)[t_max] - minimal_max_knot) <
+ EPSILON)
+ break;
+ }
+ else
+ if(geom_knot->nknots)
+ {
+ cnt=geom_knot->nknots;
+ for(t_min=0;t_min<cnt;t_min++)
+ if(fabs((geom_knot->knot)[t_min] - maximal_min_knot) < EPSILON)
+ break;
+ for(t_max=cnt-1;t_max;t_max--)
+ if(fabs((geom_knot->knot)[t_max] - minimal_max_knot) < EPSILON)
+ break;
+ }
+ geom_knot->t_min=t_min;
+ geom_knot->t_max=t_max;
+ if(color_knot->unified_knot!=NULL)
+ {
+ cnt=color_knot->unified_nknots;
+ for(t_min=0;t_min<cnt;t_min++)
+ if(fabs((color_knot->unified_knot)[t_min] - maximal_min_knot) <
+ EPSILON)
+ break;
+ for(t_max=cnt-1;t_max;t_max--)
+ if(fabs((color_knot->unified_knot)[t_max] - minimal_max_knot) <
+ EPSILON)
+ break;
+ color_knot->t_min=t_min;
+ color_knot->t_max=t_max;
+ }
+ if(normal_knot->unified_knot!=NULL)
+ {
+ cnt=normal_knot->unified_nknots;
+ for(t_min=0;t_min<cnt;t_min++)
+ if(fabs((normal_knot->unified_knot)[t_min] - maximal_min_knot) <
+ EPSILON)
+ break;
+ for(t_max=cnt-1;t_max;t_max--)
+ if(fabs((normal_knot->unified_knot)[t_max] - minimal_max_knot) <
+ EPSILON)
+ break;
+ normal_knot->t_min=t_min;
+ normal_knot->t_max=t_max;
+ }
+ if(texture_knot->unified_knot!=NULL)
+ {
+ cnt=texture_knot->unified_nknots;
+ for(t_min=0;t_min<cnt;t_min++)
+ if(fabs((texture_knot->unified_knot)[t_min] - maximal_min_knot)
+ < EPSILON)
+ break;
+ for(t_max=cnt-1;t_max;t_max--)
+ if(fabs((texture_knot->unified_knot)[t_max] - minimal_max_knot)
+ < EPSILON)
+ break;
+ texture_knot->t_min=t_min;
+ texture_knot->t_max=t_max;
+ }
+ }
+}
+
+/* modify all knot valid ranges in such a way that all have the same */
+/* range, common to all knots */
+/* do this by knot insertion */
+GLenum
+select_knot_working_range(GLUnurbsObj *nobj,knot_str_type *geom_knot,
+ knot_str_type *color_knot, knot_str_type *normal_knot,
+ knot_str_type *texture_knot)
+{
+ GLint max_nknots;
+ GLfloat maximal_min_knot,minimal_max_knot;
+ GLint i;
+
+ /* find the maximum modified knot length */
+ max_nknots=geom_knot->nknots;
+ if(color_knot->unified_knot)
+ max_nknots+=color_knot->nknots;
+ if(normal_knot->unified_knot)
+ max_nknots+=normal_knot->nknots;
+ if(texture_knot->unified_knot)
+ max_nknots+=texture_knot->nknots;
+ maximal_min_knot=(geom_knot->knot)[geom_knot->t_min];
+ minimal_max_knot=(geom_knot->knot)[geom_knot->t_max];
+ /* any attirb data ? */
+ if(max_nknots!=geom_knot->nknots)
+ {
+ /* allocate space for the unified knots */
+ if((geom_knot->unified_knot=
+ (GLfloat *)malloc(sizeof(GLfloat)*max_nknots))==NULL)
+ {
+ call_user_error(nobj,GLU_OUT_OF_MEMORY);
+ return GLU_ERROR;
+ }
+ /* copy the original knot to the unified one */
+ geom_knot->unified_nknots=geom_knot->nknots;
+ for(i=0;i<geom_knot->nknots;i++)
+ (geom_knot->unified_knot)[i]=(geom_knot->knot)[i];
+ if(color_knot->unified_knot)
+ {
+ if((color_knot->knot)[color_knot->t_min] - maximal_min_knot >
+ EPSILON)
+ maximal_min_knot=(color_knot->knot)[color_knot->t_min];
+ if(minimal_max_knot - (color_knot->knot)[color_knot->t_max] >
+ EPSILON)
+ minimal_max_knot=(color_knot->knot)[color_knot->t_max];
+ if((color_knot->unified_knot=
+ (GLfloat *)malloc(sizeof(GLfloat)*max_nknots))==NULL)
+ {
+ free(geom_knot->unified_knot);
+ call_user_error(nobj,GLU_OUT_OF_MEMORY);
+ return GLU_ERROR;
+ }
+ /* copy the original knot to the unified one */
+ color_knot->unified_nknots=color_knot->nknots;
+ for(i=0;i<color_knot->nknots;i++)
+ (color_knot->unified_knot)[i]=(color_knot->knot)[i];
+ }
+ if(normal_knot->unified_knot)
+ {
+ if((normal_knot->knot)[normal_knot->t_min] - maximal_min_knot >
+ EPSILON)
+ maximal_min_knot=(normal_knot->knot)[normal_knot->t_min];
+ if(minimal_max_knot - (normal_knot->knot)[normal_knot->t_max] >
+ EPSILON)
+ minimal_max_knot=(normal_knot->knot)[normal_knot->t_max];
+ if((normal_knot->unified_knot=
+ (GLfloat *)malloc(sizeof(GLfloat)*max_nknots))==NULL)
+ {
+ free(geom_knot->unified_knot);
+ free(color_knot->unified_knot);
+ call_user_error(nobj,GLU_OUT_OF_MEMORY);
+ return GLU_ERROR;
+ }
+ /* copy the original knot to the unified one */
+ normal_knot->unified_nknots=normal_knot->nknots;
+ for(i=0;i<normal_knot->nknots;i++)
+ (normal_knot->unified_knot)[i]=(normal_knot->knot)[i];
+ }
+ if(texture_knot->unified_knot)
+ {
+ if((texture_knot->knot)[texture_knot->t_min] - maximal_min_knot >
+ EPSILON)
+ maximal_min_knot=(texture_knot->knot)[texture_knot->t_min];
+ if(minimal_max_knot - (texture_knot->knot)[texture_knot->t_max] >
+ EPSILON)
+ minimal_max_knot=(texture_knot->knot)[texture_knot->t_max];
+ if((texture_knot->unified_knot=
+ (GLfloat *)malloc(sizeof(GLfloat)*max_nknots))==NULL)
+ {
+ free(geom_knot->unified_knot);
+ free(color_knot->unified_knot);
+ free(normal_knot->unified_knot);
+ call_user_error(nobj,GLU_OUT_OF_MEMORY);
+ return GLU_ERROR;
+ }
+ /* copy the original knot to the unified one */
+ texture_knot->unified_nknots=texture_knot->nknots;
+ for(i=0;i<texture_knot->nknots;i++)
+ (texture_knot->unified_knot)[i]=(texture_knot->knot)[i];
+ }
+ /* work on the geometry knot with all additional knot values */
+ /* appearing in attirbutive knots */
+ if(minimal_max_knot-maximal_min_knot < EPSILON)
+ {
+ /* empty working range */
+ geom_knot->unified_nknots=0;
+ color_knot->unified_nknots=0;
+ normal_knot->unified_nknots=0;
+ texture_knot->unified_nknots=0;
+ }
+ else
+ {
+ if(color_knot->unified_knot)
+ collect_unified_knot(geom_knot,color_knot,maximal_min_knot,
+ minimal_max_knot);
+ if(normal_knot->unified_knot)
+ collect_unified_knot(geom_knot,normal_knot,maximal_min_knot,
+ minimal_max_knot);
+ if(texture_knot->unified_knot)
+ collect_unified_knot(geom_knot,texture_knot,maximal_min_knot,
+ minimal_max_knot);
+ /* since we have now built the "unified" geometry knot */
+ /* add same knot values to all attributive knots */
+ if(color_knot->unified_knot)
+ collect_unified_knot(color_knot,geom_knot,maximal_min_knot,
+ minimal_max_knot);
+ if(normal_knot->unified_knot)
+ collect_unified_knot(normal_knot,geom_knot,maximal_min_knot,
+ minimal_max_knot);
+ if(texture_knot->unified_knot)
+ collect_unified_knot(texture_knot,geom_knot,maximal_min_knot,
+ minimal_max_knot);
+ }
+ }
+ set_new_t_min_t_max(geom_knot,color_knot,normal_knot,texture_knot,
+ maximal_min_knot,minimal_max_knot);
+ return GLU_NO_ERROR;
+}
+
+void
+free_unified_knots(knot_str_type *geom_knot, knot_str_type *color_knot,
+ knot_str_type *normal_knot, knot_str_type *texture_knot)
+{
+ if(geom_knot->unified_knot)
+ free(geom_knot->unified_knot);
+ if(color_knot->unified_knot)
+ free(color_knot->unified_knot);
+ if(normal_knot->unified_knot)
+ free(normal_knot->unified_knot);
+ if(texture_knot->unified_knot)
+ free(texture_knot->unified_knot);
+}
+
+GLenum
+explode_knot(knot_str_type *the_knot)
+{
+ GLfloat *knot,*new_knot;
+ GLint nknots,n_new_knots=0;
+ GLint t_min,t_max;
+ GLint ord;
+ GLsizei i,j,k;
+ GLfloat tmp_float;
+
+ if(the_knot->unified_knot)
+ {
+ knot=the_knot->unified_knot;
+ nknots=the_knot->unified_nknots;
+ }
+ else
+ {
+ knot=the_knot->knot;
+ nknots=the_knot->nknots;
+ }
+ ord=the_knot->order;
+ t_min=the_knot->t_min;
+ t_max=the_knot->t_max;
+
+ for(i=t_min;i<=t_max;)
+ {
+ tmp_float=knot[i];
+ for(j=0;j<ord && (i+j)<=t_max;j++)
+ if(fabs(tmp_float-knot[i+j])>EPSILON)
+ break;
+ n_new_knots+=ord-j;
+ i+=j;
+ }
+ /* alloc space for new_knot */
+ if((new_knot=(GLfloat *)malloc(sizeof(GLfloat)*(nknots+n_new_knots)))==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ /* fill in new knot */
+ for(j=0;j<t_min;j++)
+ new_knot[j]=knot[j];
+ for(i=j;i<=t_max;i++)
+ {
+ tmp_float=knot[i];
+ for(k=0;k<ord;k++)
+ {
+ new_knot[j++]=knot[i];
+ if(tmp_float==knot[i+1])
+ i++;
+ }
+ }
+ for(i=t_max+1;i<(int)nknots;i++)
+ new_knot[j++]=knot[i];
+ /* fill in the knot structure */
+ the_knot->new_knot=new_knot;
+ the_knot->delta_nknots+=n_new_knots;
+ the_knot->t_max+=n_new_knots;
+ return GLU_NO_ERROR;
+}
+
+GLenum
+calc_alphas(knot_str_type *the_knot)
+{
+ GLfloat tmp_float;
+ int i,j,k,m,n;
+ int order;
+ GLfloat *alpha,*alpha_new,*tmp_alpha;
+ GLfloat denom;
+ GLfloat *knot,*new_knot;
+
+
+ knot=the_knot->knot;
+ order=the_knot->order;
+ new_knot=the_knot->new_knot;
+ n=the_knot->nknots-the_knot->order;
+ m=n+the_knot->delta_nknots;
+ if((alpha=(GLfloat *)malloc(sizeof(GLfloat)*n*m))==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ if((alpha_new=(GLfloat *)malloc(sizeof(GLfloat)*n*m))==NULL)
+ {
+ free(alpha);
+ return GLU_OUT_OF_MEMORY;
+ }
+ for(j=0;j<m;j++)
+ {
+ for(i=0;i<n;i++)
+ {
+ if((knot[i] <= new_knot[j]) && (new_knot[j] < knot[i+1]))
+ tmp_float=1.0;
+ else
+ tmp_float=0.0;
+ alpha[i+j*n]=tmp_float;
+ }
+ }
+ for(k=1;k<order;k++)
+ {
+ for(j=0;j<m;j++)
+ for(i=0;i<n;i++)
+ {
+ denom=knot[i+k]-knot[i];
+ if(fabs(denom)<EPSILON)
+ tmp_float=0.0;
+ else
+ tmp_float=(new_knot[j+k]-knot[i])/denom*
+ alpha[i+j*n];
+ denom=knot[i+k+1]-knot[i+1];
+ if(fabs(denom)>EPSILON)
+ tmp_float+=(knot[i+k+1]-new_knot[j+k])/denom*
+ alpha[(i+1)+j*n];
+ alpha_new[i+j*n]=tmp_float;
+ }
+ tmp_alpha=alpha_new;
+ alpha_new=alpha;
+ alpha=tmp_alpha;
+ }
+ the_knot->alpha=alpha;
+ free(alpha_new);
+ return GLU_NO_ERROR;
+}
+
+GLenum
+calc_new_ctrl_pts(GLfloat *ctrl,GLint stride,knot_str_type *the_knot,
+ GLint dim,GLfloat **new_ctrl,GLint *ncontrol)
+{
+ GLsizei i,j,k,l,m,n;
+ GLsizei index1,index2;
+ GLfloat *alpha;
+ GLfloat *new_knot;
+
+ new_knot=the_knot->new_knot;
+ n=the_knot->nknots-the_knot->order;
+ alpha=the_knot->alpha;
+
+ m=the_knot->t_max+1-the_knot->t_min-the_knot->order;
+ k=the_knot->t_min;
+ /* allocate space for new control points */
+ if((*new_ctrl=(GLfloat *)malloc(sizeof(GLfloat)*dim*m))==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ for(j=0;j<m;j++)
+ {
+ for(l=0;l<dim;l++)
+ (*new_ctrl)[j*dim+l]=0.0;
+ for(i=0;i<n;i++)
+ {
+ index1=i+(j+k)*n;
+ index2=i*stride;
+ for(l=0;l<dim;l++)
+ (*new_ctrl)[j*dim+l]+=alpha[index1]*ctrl[index2+l];
+ }
+ }
+ *ncontrol=(GLint)m;
+ return GLU_NO_ERROR;
+}
+
+static GLint
+calc_factor(GLfloat *pts,GLint order,GLint indx,GLint stride,GLfloat tolerance,
+ GLint dim)
+{
+ GLdouble model[16],proj[16];
+ GLint viewport[4];
+ GLdouble x,y,z,w,winx1,winy1,winz,winx2,winy2;
+ GLint i;
+ GLdouble len,dx,dy;
+
+ glGetDoublev(GL_MODELVIEW_MATRIX,model);
+ glGetDoublev(GL_PROJECTION_MATRIX,proj);
+ glGetIntegerv(GL_VIEWPORT,viewport);
+ if(dim==4)
+ {
+ w=(GLdouble)pts[indx+3];
+ x=(GLdouble)pts[indx]/w;
+ y=(GLdouble)pts[indx+1]/w;
+ z=(GLdouble)pts[indx+2]/w;
+ gluProject(x,y,z,model,proj,viewport,&winx1,&winy1,&winz);
+ len=0.0;
+ for(i=1;i<order;i++)
+ {
+ w=(GLdouble)pts[indx+i*stride+3];
+ x=(GLdouble)pts[indx+i*stride]/w;
+ y=(GLdouble)pts[indx+i*stride+1]/w;
+ z=(GLdouble)pts[indx+i*stride+2]/w;
+ if(gluProject(x,y,z,model,proj,viewport,&winx2,&winy2,&winz))
+ {
+ dx=winx2-winx1;
+ dy=winy2-winy1;
+ len+=sqrt(dx*dx+dy*dy);
+ }
+ winx1=winx2; winy1=winy2;
+ }
+ }
+ else
+ {
+ x=(GLdouble)pts[indx];
+ y=(GLdouble)pts[indx+1];
+ if(dim==2)
+ z=0.0;
+ else
+ z=(GLdouble)pts[indx+2];
+ gluProject(x,y,z,model,proj,viewport,&winx1,&winy1,&winz);
+ len=0.0;
+ for(i=1;i<order;i++)
+ {
+ x=(GLdouble)pts[indx+i*stride];
+ y=(GLdouble)pts[indx+i*stride+1];
+ if(dim==2)
+ z=0.0;
+ else
+ z=(GLdouble)pts[indx+i*stride+2];
+ if(gluProject(x,y,z,model,proj,viewport,&winx2,&winy2,&winz))
+ {
+ dx=winx2-winx1;
+ dy=winy2-winy1;
+ len+=sqrt(dx*dx+dy*dy);
+ }
+ winx1=winx2; winy1=winy2;
+ }
+ }
+ len /= tolerance;
+ return ((GLint)len+1);
+}
+
+/* we can't use the Mesa evaluators - no way to get the point coords */
+/* so we use our own Bezier point calculus routines */
+/* because I'm lazy, I reuse the ones from eval.c */
+
+static void
+bezier_curve(GLfloat *cp, GLfloat *out, GLfloat t,
+ GLuint dim, GLuint order, GLint offset)
+{
+ GLfloat s, powert;
+ GLuint i, k, bincoeff;
+
+ if(order >= 2)
+ {
+ bincoeff = order-1;
+ s = 1.0-t;
+
+ for(k=0; k<dim; k++)
+ out[k] = s*cp[k] + bincoeff*t*cp[offset+k];
+
+ for(i=2, cp+=2*offset, powert=t*t; i<order; i++, powert*=t, cp +=offset)
+ {
+ bincoeff *= order-i;
+ bincoeff /= i;
+
+ for(k=0; k<dim; k++)
+ out[k] = s*out[k] + bincoeff*powert*cp[k];
+ }
+ }
+ else /* order=1 -> constant curve */
+ {
+ for(k=0; k<dim; k++)
+ out[k] = cp[k];
+ }
+}
+
+static GLint
+calc_parametric_factor(GLfloat *pts,GLint order,GLint indx,GLint stride,
+ GLfloat tolerance,GLint dim)
+{
+ GLdouble model[16],proj[16];
+ GLint viewport[4];
+ GLdouble x,y,z,w,x1,y1,z1,x2,y2,z2,x3,y3,z3;
+ GLint i;
+ GLint P;
+ GLfloat bez_pt[4];
+ GLdouble len=0.0,tmp,z_med;
+
+ P = 2*(order+2);
+ glGetDoublev(GL_MODELVIEW_MATRIX,model);
+ glGetDoublev(GL_PROJECTION_MATRIX,proj);
+ glGetIntegerv(GL_VIEWPORT,viewport);
+ z_med = (viewport[2] + viewport[3]) * 0.5;
+ switch(dim)
+ {
+ case 4:
+ for(i=1;i<P;i++)
+ {
+ bezier_curve(pts+indx, bez_pt, (GLfloat)i/(GLfloat)P, 4,
+ order,stride);
+ w = (GLdouble)bez_pt[3];
+ x = (GLdouble)bez_pt[0] / w;
+ y = (GLdouble)bez_pt[1] / w;
+ z = (GLdouble)bez_pt[2] / w;
+ gluProject(x,y,z,model,proj,viewport,&x3,&y3,&z3);
+ z3 *= z_med;
+ bezier_curve(pts+indx, bez_pt, (GLfloat)(i-1)/(GLfloat)P, 4,
+ order,stride);
+ w = (GLdouble)bez_pt[3];
+ x = (GLdouble)bez_pt[0] / w;
+ y = (GLdouble)bez_pt[1] / w;
+ z = (GLdouble)bez_pt[2] / w;
+ gluProject(x,y,z,model,proj,viewport,&x1,&y1,&z1);
+ z1 *= z_med;
+ bezier_curve(pts+indx, bez_pt, (GLfloat)(i+1)/(GLfloat)P, 4,
+ order,stride);
+ w = (GLdouble)bez_pt[3];
+ x = (GLdouble)bez_pt[0] / w;
+ y = (GLdouble)bez_pt[1] / w;
+ z = (GLdouble)bez_pt[2] / w;
+ gluProject(x,y,z,model,proj,viewport,&x2,&y2,&z2);
+ z2 *= z_med;
+ /* calc distance between point (x3,y3,z3) and line segment */
+ /* <x1,y1,z1><x2,y2,z2> */
+ x = x2-x1;
+ y = y2-y1;
+ z = z2-z1;
+ tmp = sqrt(x*x+y*y+z*z);
+ x /= tmp;
+ y /= tmp;
+ z /= tmp;
+ tmp = x3*x+y3*y+z3*z-x1*x-y1*y-z1*z;
+ x = x1+x*tmp-x3;
+ y = y1+y*tmp-y3;
+ z = z1+z*tmp-z3;
+ tmp = sqrt(x*x+y*y+z*z);
+ if(tmp > len)
+ len = tmp;
+ }
+ break;
+ case 3:
+ for(i=1;i<P;i++)
+ {
+ bezier_curve(pts+indx, bez_pt, (GLfloat)i/(GLfloat)P, 3,
+ order,stride);
+ x = (GLdouble)bez_pt[0];
+ y = (GLdouble)bez_pt[1];
+ z = (GLdouble)bez_pt[2];
+ gluProject(x,y,z,model,proj,viewport,&x3,&y3,&z3);
+ z3 *= z_med;
+ bezier_curve(pts+indx, bez_pt, (GLfloat)(i-1)/(GLfloat)P, 3,
+ order,stride);
+ x = (GLdouble)bez_pt[0];
+ y = (GLdouble)bez_pt[1];
+ z = (GLdouble)bez_pt[2];
+ gluProject(x,y,z,model,proj,viewport,&x1,&y1,&z1);
+ z1 *= z_med;
+ bezier_curve(pts+indx, bez_pt, (GLfloat)(i+1)/(GLfloat)P, 3,
+ order,stride);
+ x = (GLdouble)bez_pt[0];
+ y = (GLdouble)bez_pt[1];
+ z = (GLdouble)bez_pt[2];
+ gluProject(x,y,z,model,proj,viewport,&x2,&y2,&z2);
+ z2 *= z_med;
+ /* calc distance between point (x3,y3,z3) and line segment */
+ /* <x1,y1,z1><x2,y2,z2> */
+ x = x2-x1;
+ y = y2-y1;
+ z = z2-z1;
+ tmp = sqrt(x*x+y*y+z*z);
+ x /= tmp;
+ y /= tmp;
+ z /= tmp;
+ tmp = x3*x+y3*y+z3*z-x1*x-y1*y-z1*z;
+ x = x1+x*tmp-x3;
+ y = y1+y*tmp-y3;
+ z = z1+z*tmp-z3;
+ tmp = sqrt(x*x+y*y+z*z);
+ if(tmp > len)
+ len = tmp;
+ }
+ break;
+ case 2:
+ for(i=1;i<P;i++)
+ {
+ bezier_curve(pts+indx, bez_pt, (GLfloat)i/(GLfloat)P, 2,
+ order,stride);
+ x = (GLdouble)bez_pt[0];
+ y = (GLdouble)bez_pt[1];
+ z = 0.0;
+ gluProject(x,y,z,model,proj,viewport,&x3,&y3,&z3);
+ z3 *= z_med;
+ bezier_curve(pts+indx, bez_pt, (GLfloat)(i-1)/(GLfloat)P, 2,
+ order,stride);
+ x = (GLdouble)bez_pt[0];
+ y = (GLdouble)bez_pt[1];
+ z = 0.0;
+ gluProject(x,y,z,model,proj,viewport,&x1,&y1,&z1);
+ z1 *= z_med;
+ bezier_curve(pts+indx, bez_pt, (GLfloat)(i+1)/(GLfloat)P, 2,
+ order,stride);
+ x = (GLdouble)bez_pt[0];
+ y = (GLdouble)bez_pt[1];
+ z = 0.0;
+ gluProject(x,y,z,model,proj,viewport,&x2,&y2,&z2);
+ z2 *= z_med;
+ /* calc distance between point (x3,y3,z3) and line segment */
+ /* <x1,y1,z1><x2,y2,z2> */
+ x = x2-x1;
+ y = y2-y1;
+ z = z2-z1;
+ tmp = sqrt(x*x+y*y+z*z);
+ x /= tmp;
+ y /= tmp;
+ z /= tmp;
+ tmp = x3*x+y3*y+z3*z-x1*x-y1*y-z1*z;
+ x = x1+x*tmp-x3;
+ y = y1+y*tmp-y3;
+ z = z1+z*tmp-z3;
+ tmp = sqrt(x*x+y*y+z*z);
+ if(tmp > len)
+ len = tmp;
+ }
+ break;
+
+ }
+ if(len < tolerance)
+ return (order);
+ else
+ return (GLint)(sqrt(len/tolerance)*(order+2)+1);
+}
+
+static GLenum
+calc_sampling_3D(new_ctrl_type *new_ctrl, GLfloat tolerance, GLint dim,
+ GLint uorder, GLint vorder, GLint **ufactors, GLint **vfactors)
+{
+ GLfloat *ctrl;
+ GLint tmp_factor1,tmp_factor2;
+ GLint ufactor_cnt,vfactor_cnt;
+ GLint offset1,offset2,offset3;
+ GLint i,j;
+
+ ufactor_cnt=new_ctrl->s_bezier_cnt;
+ vfactor_cnt=new_ctrl->t_bezier_cnt;
+ if((*ufactors=(GLint *)malloc(sizeof(GLint)*ufactor_cnt*3))
+ ==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ if((*vfactors=(GLint *)malloc(sizeof(GLint)*vfactor_cnt*3))
+ ==NULL)
+ {
+ free(*ufactors);
+ return GLU_OUT_OF_MEMORY;
+ }
+ ctrl=new_ctrl->geom_ctrl;
+ offset1=new_ctrl->geom_t_stride*vorder;
+ offset2=new_ctrl->geom_s_stride*uorder;
+ for(j=0;j<vfactor_cnt;j++)
+ {
+ *(*vfactors+j*3+1)=tmp_factor1=calc_factor(ctrl,vorder,
+ j*offset1,dim,tolerance,dim);
+ /* loop ufactor_cnt-1 times */
+ for(i=1;i<ufactor_cnt;i++)
+ {
+ tmp_factor2=calc_factor(ctrl,vorder,
+ j*offset1+i*offset2,dim,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ tmp_factor1=tmp_factor2;
+ }
+ /* last time for the opposite edge */
+ *(*vfactors+j*3+2)=tmp_factor2=calc_factor(ctrl,vorder,
+ j*offset1+i*offset2-new_ctrl->geom_s_stride,
+ dim,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ *(*vfactors+j*3)=tmp_factor2;
+ else
+ *(*vfactors+j*3)=tmp_factor1;
+ }
+ offset3=new_ctrl->geom_s_stride;
+ offset2=new_ctrl->geom_s_stride*uorder;
+ for(j=0;j<ufactor_cnt;j++)
+ {
+ *(*ufactors+j*3+1)=tmp_factor1=calc_factor(ctrl,uorder,
+ j*offset2,offset3,tolerance,dim);
+ /* loop vfactor_cnt-1 times */
+ for(i=1;i<vfactor_cnt;i++)
+ {
+ tmp_factor2=calc_factor(ctrl,uorder,
+ j*offset2+i*offset1,offset3,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ tmp_factor1=tmp_factor2;
+ }
+ /* last time for the opposite edge */
+ *(*ufactors+j*3+2)=tmp_factor2=calc_factor(ctrl,uorder,
+ j*offset2+i*offset1-new_ctrl->geom_t_stride,
+ offset3,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ *(*ufactors+j*3)=tmp_factor2;
+ else
+ *(*ufactors+j*3)=tmp_factor1;
+ }
+ return GL_NO_ERROR;
+}
+
+static GLenum
+calc_sampling_param_3D(new_ctrl_type *new_ctrl, GLfloat tolerance, GLint dim,
+ GLint uorder, GLint vorder, GLint **ufactors, GLint **vfactors)
+{
+ GLfloat *ctrl;
+ GLint tmp_factor1,tmp_factor2;
+ GLint ufactor_cnt,vfactor_cnt;
+ GLint offset1,offset2,offset3;
+ GLint i,j;
+
+ ufactor_cnt=new_ctrl->s_bezier_cnt;
+ vfactor_cnt=new_ctrl->t_bezier_cnt;
+ if((*ufactors=(GLint *)malloc(sizeof(GLint)*ufactor_cnt*3))
+ ==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ if((*vfactors=(GLint *)malloc(sizeof(GLint)*vfactor_cnt*3))
+ ==NULL)
+ {
+ free(*ufactors);
+ return GLU_OUT_OF_MEMORY;
+ }
+ ctrl=new_ctrl->geom_ctrl;
+ offset1=new_ctrl->geom_t_stride*vorder;
+ offset2=new_ctrl->geom_s_stride*uorder;
+ for(j=0;j<vfactor_cnt;j++)
+ {
+ *(*vfactors+j*3+1)=tmp_factor1=calc_parametric_factor(ctrl,vorder,
+ j*offset1,dim,tolerance,dim);
+ /* loop ufactor_cnt-1 times */
+ for(i=1;i<ufactor_cnt;i++)
+ {
+ tmp_factor2=calc_parametric_factor(ctrl,vorder,
+ j*offset1+i*offset2,dim,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ tmp_factor1=tmp_factor2;
+ }
+ /* last time for the opposite edge */
+ *(*vfactors+j*3+2)=tmp_factor2=calc_parametric_factor(ctrl,vorder,
+ j*offset1+i*offset2-new_ctrl->geom_s_stride,
+ dim,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ *(*vfactors+j*3)=tmp_factor2;
+ else
+ *(*vfactors+j*3)=tmp_factor1;
+ }
+ offset3=new_ctrl->geom_s_stride;
+ offset2=new_ctrl->geom_s_stride*uorder;
+ for(j=0;j<ufactor_cnt;j++)
+ {
+ *(*ufactors+j*3+1)=tmp_factor1=calc_parametric_factor(ctrl,uorder,
+ j*offset2,offset3,tolerance,dim);
+ /* loop vfactor_cnt-1 times */
+ for(i=1;i<vfactor_cnt;i++)
+ {
+ tmp_factor2=calc_parametric_factor(ctrl,uorder,
+ j*offset2+i*offset1,offset3,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ tmp_factor1=tmp_factor2;
+ }
+ /* last time for the opposite edge */
+ *(*ufactors+j*3+2)=tmp_factor2=calc_parametric_factor(ctrl,uorder,
+ j*offset2+i*offset1-new_ctrl->geom_t_stride,
+ offset3,tolerance,dim);
+ if(tmp_factor2>tmp_factor1)
+ *(*ufactors+j*3)=tmp_factor2;
+ else
+ *(*ufactors+j*3)=tmp_factor1;
+ }
+ return GL_NO_ERROR;
+}
+
+static GLenum
+calc_sampling_2D(GLfloat *ctrl, GLint cnt, GLint order,
+ GLfloat tolerance, GLint dim, GLint **factors)
+{
+ GLint factor_cnt;
+ GLint tmp_factor;
+ GLint offset;
+ GLint i;
+
+ factor_cnt=cnt/order;
+ if((*factors=(GLint *)malloc(sizeof(GLint)*factor_cnt))==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ offset=order*dim;
+ for(i=0;i<factor_cnt;i++)
+ {
+ tmp_factor=calc_factor(ctrl,order,i*offset,dim,tolerance,dim);
+ if(tmp_factor == 0)
+ (*factors)[i]=1;
+ else
+ (*factors)[i]=tmp_factor;
+ }
+ return GL_NO_ERROR;
+}
+
+static void
+set_sampling_and_culling( GLUnurbsObj *nobj )
+{
+ if(nobj->auto_load_matrix==GL_FALSE)
+ {
+ GLint i;
+ GLfloat m[4];
+
+ glPushAttrib( (GLbitfield) (GL_VIEWPORT_BIT | GL_TRANSFORM_BIT));
+ for(i=0;i<4;i++)
+ m[i]=nobj->sampling_matrices.viewport[i];
+ glViewport(m[0],m[1],m[2],m[3]);
+ glMatrixMode(GL_PROJECTION);
+ glPushMatrix();
+ glLoadMatrixf(nobj->sampling_matrices.proj);
+ glMatrixMode(GL_MODELVIEW);
+ glPushMatrix();
+ glLoadMatrixf(nobj->sampling_matrices.model);
+ }
+}
+
+static void
+revert_sampling_and_culling( GLUnurbsObj *nobj )
+{
+ if(nobj->auto_load_matrix==GL_FALSE)
+ {
+ glMatrixMode(GL_MODELVIEW);
+ glPopMatrix();
+ glMatrixMode(GL_PROJECTION);
+ glPopMatrix();
+ glPopAttrib();
+ }
+}
+
+GLenum
+glu_do_sampling_3D( GLUnurbsObj *nobj, new_ctrl_type *new_ctrl,
+ GLint **sfactors, GLint **tfactors)
+{
+ GLint dim;
+ GLenum err;
+
+ *sfactors=NULL;
+ *tfactors=NULL;
+ dim=nobj->surface.geom.dim;
+ set_sampling_and_culling(nobj);
+ if((err=calc_sampling_3D(new_ctrl,nobj->sampling_tolerance,dim,
+ nobj->surface.geom.sorder,nobj->surface.geom.torder,
+ sfactors,tfactors))==GLU_ERROR)
+ {
+ revert_sampling_and_culling(nobj);
+ call_user_error(nobj,err);
+ return GLU_ERROR;
+ }
+ revert_sampling_and_culling(nobj);
+ return GLU_NO_ERROR;
+}
+
+GLenum
+glu_do_sampling_uv( GLUnurbsObj *nobj, new_ctrl_type *new_ctrl,
+ GLint **sfactors, GLint **tfactors)
+{
+ GLint s_cnt, t_cnt, i;
+ GLint u_steps, v_steps;
+
+ s_cnt = new_ctrl->s_bezier_cnt;
+ t_cnt = new_ctrl->t_bezier_cnt;
+ *sfactors=NULL;
+ *tfactors=NULL;
+ if((*sfactors=(GLint *)malloc(sizeof(GLint)*s_cnt*3))
+ ==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ if((*tfactors=(GLint *)malloc(sizeof(GLint)*t_cnt*3))
+ ==NULL)
+ {
+ free(*sfactors);
+ return GLU_OUT_OF_MEMORY;
+ }
+ u_steps = nobj->u_step;
+ v_steps = nobj->v_step;
+ for(i=0; i<s_cnt; i++)
+ {
+ *(*sfactors+i*3) = u_steps;
+ *(*sfactors+i*3+1) = u_steps;
+ *(*sfactors+i*3+2) = u_steps;
+ }
+ for(i=0; i<t_cnt; i++)
+ {
+ *(*tfactors+i*3) = v_steps;
+ *(*tfactors+i*3+1) = v_steps;
+ *(*tfactors+i*3+2) = v_steps;
+ }
+ return GLU_NO_ERROR;
+}
+
+GLenum
+glu_do_sampling_param_3D( GLUnurbsObj *nobj, new_ctrl_type *new_ctrl,
+ GLint **sfactors, GLint **tfactors)
+{
+ GLint dim;
+ GLenum err;
+
+ *sfactors=NULL;
+ *tfactors=NULL;
+ dim=nobj->surface.geom.dim;
+ set_sampling_and_culling(nobj);
+ if((err=calc_sampling_param_3D(new_ctrl,nobj->parametric_tolerance,dim,
+ nobj->surface.geom.sorder,nobj->surface.geom.torder,
+ sfactors,tfactors))==GLU_ERROR)
+ {
+ revert_sampling_and_culling(nobj);
+ call_user_error(nobj,err);
+ return GLU_ERROR;
+ }
+ revert_sampling_and_culling(nobj);
+ return GLU_NO_ERROR;
+}
+
+GLenum
+glu_do_sampling_2D( GLUnurbsObj *nobj, GLfloat *ctrl, GLint cnt, GLint order,
+ GLint dim, GLint **factors)
+{
+ GLenum err;
+
+ set_sampling_and_culling(nobj);
+ err=calc_sampling_2D(ctrl,cnt,order,nobj->sampling_tolerance,dim,
+ factors);
+ revert_sampling_and_culling(nobj);
+ return err;
+}
+
+
+GLenum
+glu_do_sampling_u( GLUnurbsObj *nobj, GLfloat *ctrl, GLint cnt, GLint order,
+ GLint dim, GLint **factors)
+{
+ GLint i;
+ GLint u_steps;
+
+ cnt /= order;
+ if((*factors=(GLint *)malloc(sizeof(GLint)*cnt))
+ ==NULL)
+ {
+ return GLU_OUT_OF_MEMORY;
+ }
+ u_steps = nobj->u_step;
+ for(i=0; i<cnt; i++)
+ (*factors)[i] = u_steps;
+ return GLU_NO_ERROR;
+}
+
+GLenum
+glu_do_sampling_param_2D( GLUnurbsObj *nobj, GLfloat *ctrl, GLint cnt,
+ GLint order, GLint dim, GLint **factors)
+{
+ GLint i;
+ GLint u_steps;
+ GLfloat tolerance;
+
+ set_sampling_and_culling(nobj);
+ tolerance = nobj->parametric_tolerance;
+ cnt /= order;
+ if((*factors=(GLint *)malloc(sizeof(GLint)*cnt))
+ ==NULL)
+ {
+ revert_sampling_and_culling(nobj);
+ return GLU_OUT_OF_MEMORY;
+ }
+ u_steps = nobj->u_step;
+ for(i=0; i<cnt; i++)
+ {
+ (*factors)[i] = calc_parametric_factor(ctrl,order,0,
+ dim,tolerance,dim);
+
+ }
+ revert_sampling_and_culling(nobj);
+ return GLU_NO_ERROR;
+}
+
+GLenum
+glu_do_sampling_crv( GLUnurbsObj *nobj, GLfloat *ctrl, GLint cnt, GLint order,
+ GLint dim, GLint **factors)
+{
+ GLenum err;
+
+ *factors=NULL;
+ switch(nobj->sampling_method)
+ {
+ case GLU_PATH_LENGTH:
+ if((err=glu_do_sampling_2D(nobj,ctrl,cnt,order,dim,factors))!=
+ GLU_NO_ERROR)
+ {
+ call_user_error(nobj,err);
+ return GLU_ERROR;
+ }
+ break;
+ case GLU_DOMAIN_DISTANCE:
+ if((err=glu_do_sampling_u(nobj,ctrl,cnt,order,dim,factors))!=
+ GLU_NO_ERROR)
+ {
+ call_user_error(nobj,err);
+ return GLU_ERROR;
+ }
+ break;
+ case GLU_PARAMETRIC_ERROR:
+ if((err=glu_do_sampling_param_2D(nobj,ctrl,cnt,order,dim,factors))!=
+ GLU_NO_ERROR)
+ {
+ call_user_error(nobj,err);
+ return GLU_ERROR;
+ }
+ break;
+ default:
+ abort();
+ }
+
+ return GLU_NO_ERROR;
+}
+
+/* TODO - i don't like this culling - this one just tests if at least one */
+/* ctrl point lies within the viewport . Also the point_in_viewport() */
+/* should be included in the fnctions for efficiency reasons */
+
+static GLboolean
+point_in_viewport(GLfloat *pt, GLint dim)
+{
+ GLdouble model[16],proj[16];
+ GLint viewport[4];
+ GLdouble x,y,z,w,winx,winy,winz;
+
+ glGetDoublev(GL_MODELVIEW_MATRIX,model);
+ glGetDoublev(GL_PROJECTION_MATRIX,proj);
+ glGetIntegerv(GL_VIEWPORT,viewport);
+ if(dim==3)
+ {
+ x=(GLdouble)pt[0];
+ y=(GLdouble)pt[1];
+ z=(GLdouble)pt[2];
+ gluProject(x,y,z,model,proj,viewport,&winx,&winy,&winz);
+ }
+ else
+ {
+ w=(GLdouble)pt[3];
+ x=(GLdouble)pt[0]/w;
+ y=(GLdouble)pt[1]/w;
+ z=(GLdouble)pt[2]/w;
+ gluProject(x,y,z,model,proj,viewport,&winx,&winy,&winz);
+ }
+ if((GLint)winx >= viewport[0] && (GLint)winx < viewport[2] &&
+ (GLint)winy >= viewport[1] && (GLint)winy < viewport[3])
+ return GL_TRUE;
+ return GL_FALSE;
+}
+
+GLboolean
+fine_culling_test_3D(GLUnurbsObj *nobj,GLfloat *pts,GLint s_cnt,GLint t_cnt,
+ GLint s_stride,GLint t_stride, GLint dim)
+{
+ GLint i,j;
+
+ if(nobj->culling==GL_FALSE)
+ return GL_FALSE;
+ set_sampling_and_culling(nobj);
+
+ if(dim==3)
+ {
+ for(i=0;i<s_cnt;i++)
+ for(j=0;j<t_cnt;j++)
+ if(point_in_viewport(pts+i*s_stride+j*t_stride,dim))
+ {
+ revert_sampling_and_culling(nobj);
+ return GL_FALSE;
+ }
+ }
+ else
+ {
+ for(i=0;i<s_cnt;i++)
+ for(j=0;j<t_cnt;j++)
+ if(point_in_viewport(pts+i*s_stride+j*t_stride,dim))
+ {
+ revert_sampling_and_culling(nobj);
+ return GL_FALSE;
+ }
+ }
+ revert_sampling_and_culling(nobj);
+ return GL_TRUE;
+}
+
+/*GLboolean
+fine_culling_test_3D(GLUnurbsObj *nobj,GLfloat *pts,GLint s_cnt,GLint t_cnt,
+ GLint s_stride,GLint t_stride, GLint dim)
+{
+ GLint visible_cnt;
+ GLfloat feedback_buffer[5];
+ GLsizei buffer_size;
+ GLint i,j;
+
+ if(nobj->culling==GL_FALSE)
+ return GL_FALSE;
+ buffer_size=5;
+ set_sampling_and_culling(nobj);
+
+ glFeedbackBuffer(buffer_size,GL_2D,feedback_buffer);
+ glRenderMode(GL_FEEDBACK);
+ if(dim==3)
+ {
+ for(i=0;i<s_cnt;i++)
+ {
+ glBegin(GL_LINE_LOOP);
+ for(j=0;j<t_cnt;j++)
+ glVertex3fv(pts+i*s_stride+j*t_stride);
+ glEnd();
+ }
+ for(j=0;j<t_cnt;j++)
+ {
+ glBegin(GL_LINE_LOOP);
+ for(i=0;i<s_cnt;i++)
+ glVertex3fv(pts+i*s_stride+j*t_stride);
+ glEnd();
+ }
+ }
+ else
+ {
+ for(i=0;i<s_cnt;i++)
+ {
+ glBegin(GL_LINE_LOOP);
+ for(j=0;j<t_cnt;j++)
+ glVertex4fv(pts+i*s_stride+j*t_stride);
+ glEnd();
+ }
+ for(j=0;j<t_cnt;j++)
+ {
+ glBegin(GL_LINE_LOOP);
+ for(i=0;i<s_cnt;i++)
+ glVertex4fv(pts+i*s_stride+j*t_stride);
+ glEnd();
+ }
+ }
+ visible_cnt=glRenderMode(GL_RENDER);
+
+ revert_sampling_and_culling(nobj);
+ return (GLboolean)(visible_cnt==0);
+}*/
+
+GLboolean
+fine_culling_test_2D(GLUnurbsObj *nobj,GLfloat *pts,GLint cnt,
+ GLint stride, GLint dim)
+{
+ GLint i;
+
+ if(nobj->culling==GL_FALSE)
+ return GL_FALSE;
+ set_sampling_and_culling(nobj);
+
+ if(dim==3)
+ {
+ for(i=0;i<cnt;i++)
+ if(point_in_viewport(pts+i*stride,dim))
+ {
+ revert_sampling_and_culling(nobj);
+ return GL_FALSE;
+ }
+ }
+ else
+ {
+ for(i=0;i<cnt;i++)
+ if(point_in_viewport(pts+i*stride,dim))
+ {
+ revert_sampling_and_culling(nobj);
+ return GL_FALSE;
+ }
+ }
+ revert_sampling_and_culling(nobj);
+ return GL_TRUE;
+}
+
+/*GLboolean
+fine_culling_test_2D(GLUnurbsObj *nobj,GLfloat *pts,GLint cnt,
+ GLint stride, GLint dim)
+{
+ GLint visible_cnt;
+ GLfloat feedback_buffer[5];
+ GLsizei buffer_size;
+ GLint i;
+
+ if(nobj->culling==GL_FALSE)
+ return GL_FALSE;
+ buffer_size=5;
+ set_sampling_and_culling(nobj);
+
+ glFeedbackBuffer(buffer_size,GL_2D,feedback_buffer);
+ glRenderMode(GL_FEEDBACK);
+ glBegin(GL_LINE_LOOP);
+ if(dim==3)
+ {
+ for(i=0;i<cnt;i++)
+ glVertex3fv(pts+i*stride);
+ }
+ else
+ {
+ for(i=0;i<cnt;i++)
+ glVertex4fv(pts+i*stride);
+ }
+ glEnd();
+ visible_cnt=glRenderMode(GL_RENDER);
+
+ revert_sampling_and_culling(nobj);
+ return (GLboolean)(visible_cnt==0);
+}*/
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-01 00:51:05 +0000