/* * R T _ N U R B _ B E Z I E R * * Given a single snurb, if it is in Bezier form, * duplicate the snurb, and enqueue it on the bezier_hd list. * If the original snurb is NOT in Bezier form, * subdivide it a set of snurbs which are, * each of which are enqueued on the bezier_hd list. * * In either case, the original surface remains untouched. * * Returns - * 0 Surface splitting was done. * 1 Original surface was Bezier, only a copy was done. */ int rt_nurb_bezier(struct bu_list *bezier_hd, const struct face_g_snurb *orig_surf, struct resource *res) { struct face_g_snurb *s; int dir; struct bu_list todo; NMG_CK_SNURB(orig_surf); if ( (dir = rt_bez_check( orig_surf )) == -1) { s = rt_nurb_scopy( orig_surf, res ); BU_LIST_APPEND( bezier_hd, &s->l ); return 1; /* Was already Bezier, nothing done */ } BU_LIST_INIT( &todo ); rt_nurb_s_split( &todo, orig_surf, dir, res ); while ( BU_LIST_WHILE( s, face_g_snurb, &todo ) ) { if ( (dir = rt_bez_check(s)) == -1) { /* This snurb is now a Bezier */ BU_LIST_DEQUEUE( &s->l ); BU_LIST_APPEND( bezier_hd, &s->l ); } else { /* Split, and keep going */ BU_LIST_DEQUEUE( &s->l ); rt_nurb_s_split( &todo, s, dir, res ); rt_nurb_free_snurb(s, res); } } return 0; /* Bezier snurbs on bezier_hd list */ }
struct rt_nurb_uv_hit * rt_nurb_intersect(const struct face_g_snurb *srf, fastf_t *plane1, fastf_t *plane2, double uv_tol, struct resource *res, struct bu_list *plist) { struct rt_nurb_uv_hit * h; struct face_g_snurb * psrf, * osrf; int dir, sub; point_t vmin, vmax; fastf_t u[2], v[2]; struct bu_list rni_plist; NMG_CK_SNURB(srf); h = (struct rt_nurb_uv_hit *) 0; if (plist == NULL) { plist = &rni_plist; BU_LIST_INIT(plist); } /* project the surface to a 2 dimensional problem */ /* NOTE that this gives a single snurb back, NOT a list */ psrf = rt_nurb_project_srf(srf, plane2, plane1, res); psrf->dir = 1; BU_LIST_APPEND(plist, &psrf->l); if (RT_G_DEBUG & DEBUG_SPLINE) rt_nurb_s_print("srf", psrf); /* This list starts out with only a single snurb, but more may be * added on as work progresses. */ while (BU_LIST_WHILE(psrf, face_g_snurb, plist)) { int flat; BU_LIST_DEQUEUE(&psrf->l); NMG_CK_SNURB(psrf); sub = 0; flat = 0; dir = psrf->dir; while (!flat) { fastf_t smin = 0.0, smax = 0.0; sub++; dir = (dir == 0)?1:0; /* change direction */ if (RT_G_DEBUG & DEBUG_SPLINE) rt_nurb_s_print("psrf", psrf); rt_nurb_pbound(psrf, vmin, vmax); /* Check for origin to be included in the bounding box */ if (!(vmin[0] <= 0.0 && vmin[1] <= 0.0 && vmax[0] >= 0.0 && vmax[1] >= 0.0)) { if (RT_G_DEBUG & DEBUG_SPLINE) bu_log("this srf doesn't include the origin\n"); flat = 1; rt_nurb_free_snurb(psrf, res); continue; } rt_nurb_clip_srf(psrf, dir, &smin, &smax); if ((smax - smin) > .8) { struct rt_nurb_uv_hit *hp; /* Split surf, requeue both sub-surfs at head */ /* New surfs will have same dir as arg, here */ if (RT_G_DEBUG & DEBUG_SPLINE) bu_log("splitting this surface\n"); rt_nurb_s_split(plist, psrf, dir, res); rt_nurb_free_snurb(psrf, res); hp = rt_nurb_intersect(srf, plane1, plane2, uv_tol, res, plist); return hp; } if (smin > 1.0 || smax < 0.0) { if (RT_G_DEBUG & DEBUG_SPLINE) bu_log("eliminating this surface (smin=%g, smax=%g)\n", smin, smax); flat = 1; rt_nurb_free_snurb(psrf, res); continue; } if (dir == RT_NURB_SPLIT_ROW) { smin = (1.0 - smin) * psrf->u.knots[0] + smin * psrf->u.knots[ psrf->u.k_size -1]; smax = (1.0 - smax) * psrf->u.knots[0] + smax * psrf->u.knots[ psrf->u.k_size -1]; } else { smin = (1.0 - smin) * psrf->v.knots[0] + smin * psrf->v.knots[ psrf->v.k_size -1]; smax = (1.0 - smax) * psrf->v.knots[0] + smax * psrf->v.knots[ psrf->v.k_size -1]; } osrf = psrf; psrf = (struct face_g_snurb *) rt_nurb_region_from_srf( osrf, dir, smin, smax, res); psrf->dir = dir; rt_nurb_free_snurb(osrf, res); if (RT_G_DEBUG & DEBUG_SPLINE) { bu_log("After call to rt_nurb_region_from_srf() (smin=%g, smax=%g)\n", smin, smax); rt_nurb_s_print("psrf", psrf); } u[0] = psrf->u.knots[0]; u[1] = psrf->u.knots[psrf->u.k_size -1]; v[0] = psrf->v.knots[0]; v[1] = psrf->v.knots[psrf->v.k_size -1]; if ((u[1] - u[0]) < uv_tol && (v[1] - v[0]) < uv_tol) { struct rt_nurb_uv_hit * hit; if (RT_G_DEBUG & DEBUG_SPLINE) { fastf_t p1[4], p2[4]; int coords; vect_t diff; coords = RT_NURB_EXTRACT_COORDS(srf->pt_type); rt_nurb_s_eval(srf, u[0], v[0], p1); rt_nurb_s_eval(srf, u[1], v[1], p2); if (RT_NURB_IS_PT_RATIONAL(srf->pt_type)) { fastf_t inv_w; inv_w = 1.0 / p1[coords-1]; VSCALE(p1, p1, inv_w); inv_w = 1.0 / p2[coords-1]; VSCALE(p2, p2, inv_w); } VSUB2(diff, p1, p2); bu_log("Precision of hit point = %g (%f %f %f) <-> (%f %f %f)\n", MAGNITUDE(diff), V3ARGS(p1), V3ARGS(p2)); } hit = (struct rt_nurb_uv_hit *) bu_malloc( sizeof(struct rt_nurb_uv_hit), "hit"); hit->next = (struct rt_nurb_uv_hit *)0; hit->sub = sub; hit->u = (u[0] + u[1])/2.0; hit->v = (v[0] + v[1])/2.0; if (h == (struct rt_nurb_uv_hit *)0) h = hit; else { hit->next = h; h = hit; } flat = 1; rt_nurb_free_snurb(psrf, res); } if ((u[1] - u[0]) > (v[1] - v[0])) dir = 1; else dir = 0; } } return (struct rt_nurb_uv_hit *)h; }