/****************************************************************************** * Triv_aux.c - auxiliary routine to interface to tri-variate rep. * ******************************************************************************* * (C) Gershon Elber, Technion, Israel Institute of Technology * ******************************************************************************* * Written by Gershon Elber, Sep. 94. * ******************************************************************************/ #include "triv_loc.h" /***************************************************************************** * DESCRIPTION: M * Given a tri-variate, returns its parametric domain. M * * * PARAMETERS: M * TV: Trivariate function to consider. M * UMin, UMax: U Domain of TV will be placed herein. M * VMin, VMax: V Domain of TV will be placed herein. M * WMin, WMax: W Domain of TV will be placed herein. M * * * RETURN VALUE: M * void M * * * KEYWORDS: M * TrivTVDomain, trivariates M *****************************************************************************/ void TrivTVDomain(TrivTVStruct *TV, CagdRType *UMin, CagdRType *UMax, CagdRType *VMin, CagdRType *VMax, CagdRType *WMin, CagdRType *WMax) { int UOrder, VOrder, WOrder, ULen, VLen, WLen; switch (TV -> GType) { case TRIV_TVBEZIER_TYPE: *UMin = 0.0; *UMax = 1.0; *VMin = 0.0; *VMax = 1.0; *WMin = 0.0; *WMax = 1.0; break; case TRIV_TVBSPLINE_TYPE: UOrder = TV -> UOrder; VOrder = TV -> VOrder; WOrder = TV -> WOrder; ULen = TV -> ULength; VLen = TV -> VLength; WLen = TV -> WLength; *UMin = TV -> UKnotVector[UOrder - 1]; *UMax = TV -> UKnotVector[ULen]; *VMin = TV -> VKnotVector[VOrder - 1]; *VMax = TV -> VKnotVector[VLen]; *WMin = TV -> WKnotVector[WOrder - 1]; *WMax = TV -> WKnotVector[WLen]; break; default: TRIV_FATAL_ERROR(TRIV_ERR_UNDEF_GEOM); break; } } /***************************************************************************** * DESCRIPTION: M * Given a tri-variate and a domain - validate it. M * * * PARAMETERS: M * TV: To make sure t is in its Dir domain. M * t: Parameter value to verify. M * Dir: Direction. Either U or V or W. M * * * RETURN VALUE: M * CagdBType: TRUE if in domain, FALSE otherwise. M * * * KEYWORDS: M * TrivParamInDomain, trivariates M *****************************************************************************/ CagdBType TrivParamInDomain(TrivTVStruct *TV, CagdRType t, TrivTVDirType Dir) { CagdRType UMin, UMax, VMin, VMax, WMin, WMax; TrivTVDomain(TV, &UMin, &UMax, &VMin, &VMax, &WMin, &WMax); switch (Dir) { case TRIV_CONST_U_DIR: return t >= UMin && t <= UMax; case TRIV_CONST_V_DIR: return t >= VMin && t <= VMax; case TRIV_CONST_W_DIR: return t >= WMin && t <= WMax; default: TRIV_FATAL_ERROR(TRIV_ERR_WRONG_DOMAIN); return FALSE; } } /***************************************************************************** * DESCRIPTION: M * Given a tri-variate and a domain - validate it. M * * * PARAMETERS: M * TV: To make sure (u, v, w) is in its domain. M * u, v, w: To verify if it is in TV's parametric domain. M * * * RETURN VALUE: M * CagdBType: TRUE if in domain, FALSE otherwise. M * * * KEYWORDS: M * TrivParamsInDomain, trivariates M *****************************************************************************/ CagdBType TrivParamsInDomain(TrivTVStruct *TV, CagdRType u, CagdRType v, CagdRType w) { CagdRType UMin, UMax, VMin, VMax, WMin, WMax; TrivTVDomain(TV, &UMin, &UMax, &VMin, &VMax, &WMin, &WMax); return u >= UMin && u <= UMax && v >= VMin && v <= VMax && w >= WMin && w <= WMax; } /***************************************************************************** * DESCRIPTION: M * Given a tri-variate, returns a sub-region of it. M * * * PARAMETERS: M * TV: To extract asub-region from. M * t1, t1: Domain to extract from TV, in parametric direction Dir. M * Dir: Direction to extract the sub-region. Either U or V or W. M * * * RETURN VALUE: M * TrivTVStruct *: A sub-region of TV from t1 to t2 in direction Dir. M * * * KEYWORDS: M * TrivTVRegionFromTV, trivariates M *****************************************************************************/ TrivTVStruct *TrivTVRegionFromTV(TrivTVStruct *TV, CagdRType t1, CagdRType t2, TrivTVDirType Dir) { CagdRType RMin, RMax, SMin, SMax, TMin, TMax, R1, R2; TrivTVStruct *TVs; CagdBType NewTV = FALSE; switch (TV -> GType) { case TRIV_TVBEZIER_TYPE: R1 = 0.0; R2 = 1.0; break; case TRIV_TVBSPLINE_TYPE: switch (Dir) { case TRIV_CONST_U_DIR: TrivTVDomain(TV, &R1, &R2, &SMin, &SMax, &TMin, &TMax); break; case TRIV_CONST_V_DIR: TrivTVDomain(TV, &RMin, &RMax, &R1, &R2, &TMin, &TMax); break; case TRIV_CONST_W_DIR: TrivTVDomain(TV, &RMin, &RMax, &SMin, &SMax, &R1, &R2); break; default: TRIV_FATAL_ERROR(TRIV_ERR_DIR_NOT_VALID); break; } break; default: TRIV_FATAL_ERROR(TRIV_ERR_UNDEF_GEOM); return NULL; } if (t1 > t2) SWAP(CagdRType, t1, t2); if (!APX_EQ(t1, R1)) { TVs = TrivTVSubdivAtParam(TV, t1, Dir); TV = TVs -> Pnext; TVs -> Pnext = NULL; TrivTVFree(TVs); /* Free the first region. */ NewTV = TRUE; } if (APX_EQ(t2, R2)) return NewTV ? TV : TrivTVCopy(TV); else { TVs = TrivTVSubdivAtParam(TV, t2, Dir); if (NewTV) TrivTVFree(TV); TrivTVFree(TVs -> Pnext); /* Free the second region. */ TVs -> Pnext = NULL; return TVs; /* Returns the first region. */ } } /***************************************************************************** * DESCRIPTION: M * Computes a bounding box for a trivariate freeform function. M * * * PARAMETERS: M * Trivar: To compute a bounding box for. M * BBox: Where bounding information is to be saved. M * * * RETURN VALUE: M * void M * * * KEYWORDS: M * TrivTVBBox, bbox, bounding box M *****************************************************************************/ void TrivTVBBox(TrivTVStruct *Trivar, CagdBBoxStruct *BBox) { TrivTVStruct *E3TV = TrivCoerceTVTo(Trivar, CAGD_PT_E3_TYPE); int Length = E3TV -> ULength * E3TV -> VLength * E3TV -> WLength; CagdRType **Points = E3TV -> Points; CagdPointsBBox(Points, Length, BBox); TrivTVFree(E3TV); } /***************************************************************************** * DESCRIPTION: M * Computes a bounding box for a list of trivariate freeform function. M * * * PARAMETERS: M * Trivars: To compute a bounding box for. M * BBox: Where bounding information is to be saved. M * * * RETURN VALUE: M * void M * * * KEYWORDS: M * TrivTVListBBox, bbox, bounding box M *****************************************************************************/ void TrivTVListBBox(TrivTVStruct *TVs, CagdBBoxStruct *BBox) { CAGD_RESET_BBOX(BBox); for ( ; TVs != NULL; TVs = TVs -> Pnext) { CagdBBoxStruct TmpBBox; TrivTVBBox(TVs, &TmpBBox); CagdMergeBBox(BBox, &TmpBBox); } }