egs_envelope_geometry.h

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/*
###############################################################################
#
#  EGSnrc egs++ envelope geometry headers
#  Copyright (C) 2015 National Research Council Canada
#
#  This file is part of EGSnrc.
#
#  EGSnrc is free software: you can redistribute it and/or modify it under
#  the terms of the GNU Affero General Public License as published by the
#  Free Software Foundation, either version 3 of the License, or (at your
#  option) any later version.
#
#  EGSnrc 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 Affero General Public License for
#  more details.
#
#  You should have received a copy of the GNU Affero General Public License
#  along with EGSnrc. If not, see <http://www.gnu.org/licenses/>.
#
###############################################################################
#
#  Author:          Iwan Kawrakow, 2005
#
#  Contributors:    Ernesto Mainegra-Hing
#                   Frederic Tessier
#                   Reid Townson
#                   Max Orok
#                   Alexandre Demelo
#
###############################################################################
*/
 
 
#ifndef EGS_ENVELOPE_GEOMETRY_
#define EGS_ENVELOPE_GEOMETRY_
 
#ifdef WIN32
 
    #ifdef BUILD_ENVELOPEG_DLL
        #define EGS_ENVELOPEG_EXPORT __declspec(dllexport)
    #else
        #define EGS_ENVELOPEG_EXPORT __declspec(dllimport)
    #endif
    #define EGS_ENVELOPEG_LOCAL
 
#else
 
    #ifdef HAVE_VISIBILITY
        #define EGS_ENVELOPEG_EXPORT __attribute__ ((visibility ("default")))
        #define EGS_ENVELOPEG_LOCAL  __attribute__ ((visibility ("hidden")))
    #else
        #define EGS_ENVELOPEG_EXPORT
        #define EGS_ENVELOPEG_LOCAL
    #endif
 
#endif
 
 
#include "egs_base_geometry.h"
#include "egs_functions.h"
 
#include<vector>
using std::vector;
 
class EGS_ENVELOPEG_EXPORT EGS_EnvelopeGeometry : public EGS_BaseGeometry {
 
public:
 
    EGS_EnvelopeGeometry(EGS_BaseGeometry *G,
                         const vector<EGS_BaseGeometry *> &geoms, const string &Name = "",
                         bool newindexing=false);
 
    ~EGS_EnvelopeGeometry();
 
    bool isRealRegion(int ireg) const {
        if (ireg < 0 || ireg >= nreg) {
            return false;
        }
        if (ireg < nbase) {
            return g->isRealRegion(ireg);
        }
        int jg, ilocal;
        if (new_indexing) {
            jg = reg_to_inscr[ireg-nbase];
            ilocal = ireg - local_start[jg];
        }
        else {
            jg = (ireg - nbase)/nmax;
            ilocal = ireg - nbase - jg*nmax;
        }
        return geometries[jg]->isRealRegion(ilocal);
    };
 
    bool isInside(const EGS_Vector &x) {
        return g->isInside(x);
    };
 
    int isWhere(const EGS_Vector &x) {
        int ireg = g->isWhere(x);
        if (ireg < 0) {
            return ireg;
        }
        for (int j=0; j<n_in; j++) {
            int i = geometries[j]->isWhere(x);
            if (i >= 0) return new_indexing ? local_start[j] + i :
                                   nbase + nmax*j + i;
        }
        return ireg;
    };
 
    int inside(const EGS_Vector &x) {
        return isWhere(x);
    };
 
    int medium(int ireg) const {
        if (ireg < nbase) {
            return g->medium(ireg);
        }
        int jg, ilocal;
        if (new_indexing) {
            jg = reg_to_inscr[ireg-nbase];
            ilocal = ireg - local_start[jg];
        }
        else {
            jg = (ireg - nbase)/nmax;
            ilocal = ireg - nbase - jg*nmax;
        }
        return geometries[jg]->medium(ilocal);
    };
 
    int computeIntersections(int ireg, int n, const EGS_Vector &X,
                             const EGS_Vector &u, EGS_GeometryIntersections *isections) {
        if (n < 1) {
            return -1;
        }
        int ifirst = 0;
        EGS_Float t, ttot = 0;
        EGS_Vector x(X);
        int imed;
        if (ireg < 0) {
            t = veryFar;
            ireg = howfar(ireg,x,u,t,&imed);
            if (ireg < 0) {
                return 0;
            }
            isections[0].t = t;
            isections[0].rhof = 1;
            isections[0].ireg = -1;
            isections[0].imed = -1;
            ttot = t;
            ++ifirst;
            x += u*t;
        }
        else {
            imed = medium(ireg);
        }
 
 
        int j = ifirst;
        int ij = -1, ig=0;
        for (EGS_I64 loopCount=0; loopCount<=loopMax; ++loopCount) {
            if (loopCount == loopMax) {
                egsFatal("EGS_EnvelopeGeometry::computeIntersections: Too many iterations were required! Input may be invalid, or consider increasing loopMax.");
                return -1;
            }
            if (ireg >= nbase) {
                if (new_indexing) {
                    ig = reg_to_inscr[ireg-nbase];
                    ij = ireg - local_start[ig];
                }
                else {
                    ig = (ireg - nbase)/nmax;
                    ij = ireg - nbase - ig*nmax;
                }
            }
            isections[j].imed = imed;
            isections[j].ireg = ireg;
            isections[j].rhof = getRelativeRho(ireg);
            if (ireg < nbase) { // in one of the regions of the base geometry
                t = veryFar;
                int ibase = g->howfar(ireg,x,u,t,&imed);
                ij = -1;
                for (int i=0; i<n_in; i++) {
                    int ireg_i = geometries[i]->howfar(-1,x,u,t,&imed);
                    if (ireg_i >= 0) {
                        ij = ireg_i;
                        ig = i;
                    }
                }
                ttot += t;
                isections[j++].t = ttot;
                if (ij < 0) {
                    ireg = ibase;
                }
                else ireg = new_indexing ? local_start[ig] + ij :
                                nbase + ig*nmax + ij;
                if (ireg < 0) {
                    return j;
                }
                if (j >= n) {
                    return -1;
                }
                x += u*t;
            }
            else {
                int iadd = new_indexing ? local_start[ig] : nbase + ig*nmax;
                int nsec = geometries[ig]->computeIntersections(ij,n-j,
                           x,u,&isections[j]);
                int nm = nsec >= 0 ? nsec+j : n;
                for (int i=j; i<nm; i++) {
                    isections[i].ireg += iadd;
                    isections[i].t += ttot;
                }
                if (nsec < 0) {
                    return nsec;
                }
                j += nsec;
                if (j >= n) {
                    return -1;
                }
                t = isections[j-1].t - ttot;
                x += u*t;
                ttot = isections[j-1].t;
                ireg = g->isWhere(x);
                if (ireg < 0) {
                    return j;
                }
                imed = g->medium(ireg);
            }
        }
        return -1;
    }
 
    EGS_Float howfarToOutside(int ireg, const EGS_Vector &x,
                              const EGS_Vector &u) {
        if (ireg < 0) {
            return 0;
        }
        EGS_Float d;
        if (ireg < nbase) {
            d = g->howfarToOutside(ireg,x,u);
        }
        else if (g->regions() == 1) {
            d = g->howfarToOutside(0,x,u);
        }
        else {
            int ir = g->isWhere(x);
            d = g->howfarToOutside(ir,x,u);
        }
        return d;
    };
 
    int howfar(int ireg, const EGS_Vector &x, const EGS_Vector &u,
               EGS_Float &t, int *newmed = 0, EGS_Vector *normal = 0) {
        if (ireg >= 0) {
            // inside.
            if (ireg < nbase) {
                // in one of the regions of the base geometry
                // check if we hit a boundary in the base geometry.
                // if we do, newmed and normal get set accordingly.
                int ibase = g->howfar(ireg,x,u,t,newmed,normal);
                int ij = -1, jg;
                // check if we will enter any of the inscribed geometries
                // before entering a new region in the base geometry.
                for (int j=0; j<n_in; j++) {
                    int ireg_j =
                        geometries[j]->howfar(-1,x,u,t,newmed,normal);
                    if (ireg_j >= 0) {
                        // we do. remember the inscribed geometry index
                        // and local region
                        ij = ireg_j;
                        jg = j;
                    }
                }
                if (ij < 0) {
                    return ibase;
                }
                // ij<0 implies that we have not hit any of the
                // inscribed geometries => return the base geometry index.
                // ij>=0 implies that we entered inscribed geometry
                // jg in its local region ij.
                return new_indexing ? local_start[jg] + ij :
                       nbase + jg*nmax + ij;
            }
            // if here, we are in an inscribed geometry.
            // calculate its index (jg) and its local region (ilocal).
            int jg, ilocal;
            if (new_indexing) {
                jg = reg_to_inscr[ireg-nbase];
                ilocal = ireg-local_start[jg];
            }
            else {
                jg = (ireg - nbase)/nmax;
                ilocal = ireg - nbase - jg*nmax;
            }
            // and then check if we will hit a boundary in this geometry.
            int inew = geometries[jg]->howfar(ilocal,x,u,t,newmed,normal);
            if (inew >= 0) return new_indexing ? local_start[jg] + inew :
                                      nbase + jg*nmax + inew;
            // inew >= 0 implies that we either stay in the same
            // region (inew=ilocal) or we entered a new region
            // (inew!=ilocal), which is still inside the inscribed geometry
            // inew<0 implies that we have exited the inscribed geometry
            // => check to see in which base geometry region we are.
            inew = g->isWhere(x+u*t);
            if (inew >= 0 && newmed) {
                *newmed = g->medium(inew);
            }
            return inew;
        }
        // if here, we are outside the base geometry.
        // check to see if we will enter.
        int ienter = g->howfar(ireg,x,u,t,newmed,normal);
        if (ienter >= 0) {
            // yes, we do. see if we are already inside of one of the
            // inscribed geometries.
            for (int j=0; j<n_in; j++) {
                int i = geometries[j]->isWhere(x+u*t);
                if (i >= 0) {
                    // yes, we are.
                    if (newmed) {
                        *newmed = geometries[j]->medium(i);
                    }
                    return new_indexing ? local_start[j] + i :
                           nbase + nmax*j + i;
                }
            }
        }
        return ienter;
    };
 
    EGS_Float hownear(int ireg, const EGS_Vector &x) {
        if (ireg >= 0) {
            EGS_Float tmin;
            if (ireg < nbase) {  // in one of the regions of the base geom.
                tmin = g->hownear(ireg,x);
                for (int j=0; j<n_in; j++) {
                    EGS_Float tj = geometries[j]->hownear(-1,x);
                    if (tj < tmin) {
                        tmin = tj;
                        if (tmin <= 0) {
                            return tmin;
                        }
                    }
                }
                return tmin;
            }
            int jg, ilocal;
            if (new_indexing) {
                jg = reg_to_inscr[ireg-nbase];
                ilocal = ireg-local_start[jg];
            }
            else {
                jg = (ireg - nbase)/nmax;
                ilocal = ireg - nbase - jg*nmax;
            }
            return geometries[jg]->hownear(ilocal,x);
        }
        return g->hownear(ireg,x);
    };
 
 
    void getNextGeom(EGS_RandomGenerator *rndm) {
        // calls getNextGeom on its component geometries to update dynamic
        // geometries in the simulation
        for (int j=0; j<n_in; j++) {
            geometries[j]->getNextGeom(rndm);
        }
        g->getNextGeom(rndm);
    };
 
    void updatePosition(EGS_Float time) {
        // calls updatePosition on its component geometries to update dynamic
        // geometries in the simulation
        for (int j=0; j<n_in; j++) {
            geometries[j]->updatePosition(time);
        }
        g->updatePosition(time);
    };
 
    void containsDynamic(bool &hasdynamic) {
        // calls containsDynamic on its component geometries (only calls if
        // hasDynamic is false, as if it is true we already found one)
        for (int j=0; j<n_in; j++) {
            if (!hasdynamic) {
                geometries[j]->containsDynamic(hasdynamic);
            }
        }
        if (!hasdynamic) {
            g->containsDynamic(hasdynamic);
        }
    };
 
 
 
    int getMaxStep() const {
        int nstep = g->getMaxStep();
        for (int j=0; j<n_in; ++j) {
            nstep += geometries[j]->getMaxStep();
        }
        return nstep+n_in;
    };
 
    bool hasBooleanProperty(int ireg, EGS_BPType prop) const {
        if (ireg >= 0 && ireg < nreg) {
            if (ireg < nbase) {
                return g->hasBooleanProperty(ireg,prop);
            }
            int jg = (ireg - nbase)/nmax;
            int ilocal = ireg - nbase - jg*nmax;
            return geometries[jg]->hasBooleanProperty(ilocal,prop);
        }
        return false;
    };
    void setBooleanProperty(EGS_BPType) {
        setPropertyError("setBooleanProperty()");
    };
    void addBooleanProperty(int) {
        setPropertyError("addBooleanProperty()");
    };
    void setBooleanProperty(EGS_BPType,int,int,int step=1) {
        setPropertyError("setBooleanProperty()");
    };
    void addBooleanProperty(int,int,int,int step=1) {
        setPropertyError("addBooleanProperty()");
    };
 
    const string &getType() const {
        return type;
    };
 
    EGS_BaseGeometry **getInscribedGeometries(std::size_t &nInscribed) const {
        nInscribed = n_in;
        return geometries;
    }
 
    void printInfo() const;
 
    void setRelativeRho(int start, int end, EGS_Float rho);
    void setRelativeRho(EGS_Input *);
    EGS_Float getRelativeRho(int ireg) const {
        if (ireg < 0 || ireg >= nreg) {
            return 1;
        }
        if (ireg < nbase) {
            return g->getRelativeRho(ireg);
        }
        int jg = (ireg - nbase)/nmax;
        return geometries[jg]->getRelativeRho(ireg - nbase - jg*nmax);
    };
 
    void setBScaling(int start, int end, EGS_Float bf);
    void setBScaling(EGS_Input *);
    EGS_Float getBScaling(int ireg) const {
        if (ireg < 0 || ireg >= nreg) {
            return 1;
        }
        if (ireg < nbase) {
            return g->getBScaling(ireg);
        }
        int jg = (ireg - nbase)/nmax;
        return geometries[jg]->getBScaling(ireg - nbase - jg*nmax);
    };
 
    virtual void getLabelRegions(const string &str, vector<int> &regs);
 
protected:
 
    EGS_BaseGeometry *g;           
    EGS_BaseGeometry **geometries; 
    int              n_in;         
    int              nbase,   
                     nmax;    
    static string    type;    
 
    bool new_indexing;        
    int *reg_to_inscr;        
    int *local_start;         
 
    void setMedia(EGS_Input *,int,const int *);
 
private:
 
    void setPropertyError(const char *funcname) {
        egsFatal("EGS_EnvelopeGeometry::%s: don't use this method\n  Define "
                 "properties in the constituent geometries instead\n",
                 funcname);
    };
 
};
 
 
struct EnvelopeAux;
 
class EGS_ENVELOPEG_EXPORT EGS_FastEnvelope : public EGS_BaseGeometry {
 
public:
 
    EGS_FastEnvelope(EGS_BaseGeometry *G,
                     const vector<EnvelopeAux *> &fgeoms, const string &Name = "",
                     int newindexing=false);
 
    ~EGS_FastEnvelope();
 
    bool isRealRegion(int ireg) const {
        if (ireg < 0 || ireg >= nreg) {
            return false;
        }
        if (ireg < nbase) {
            return g->isRealRegion(ireg);
        }
        int jg, ilocal;
        if (new_indexing) {
            jg = reg_to_inscr[ireg-nbase];
            ilocal = ireg - local_start[jg];
        }
        else {
            jg = (ireg - nbase)/nmax;
            ilocal = ireg - nbase - jg*nmax;
        }
        return geometries[jg]->isRealRegion(ilocal);
    };
 
    bool isInside(const EGS_Vector &x) {
        return g->isInside(x);
    };
 
    int isWhere(const EGS_Vector &x) {
        int ireg = g->isWhere(x);
        if (ireg < 0 || n_start[ireg] < 0) {
            return ireg;
        }
        for (int jj=n_start[ireg]; jj<n_start[ireg+1]; jj++) {
            int j = glist[jj];
            int i = geometries[j]->isWhere(x);
            if (i >= 0) {
                return nbase + nmax*j + i;
            }
        }
        return ireg;
    };
 
    void getNextGeom(EGS_RandomGenerator *rndm) {
        // calls getNextGeom on its component geometries to update dynamic
        // geometries in the simulation
        for (int j=0; j<n_in; j++) {
            geometries[j]->getNextGeom(rndm);
        }
        g->getNextGeom(rndm);
    };
 
    void updatePosition(EGS_Float time) {
        // calls updatePosition on its component geometries to update dynamic
        // geometries in the simulation
        for (int j=0; j<n_in; j++) {
            geometries[j]->updatePosition(time);
        }
        g->updatePosition(time);
    };
 
    void containsDynamic(bool &hasdynamic) {
        // calls containsDynamic on its component geometries (only calls if
        // hasDynamic is false, as if it is true we already found one)
        for (int j=0; j<n_in; j++) {
            if (!hasdynamic) {
                geometries[j]->containsDynamic(hasdynamic);
            }
        }
        if (!hasdynamic) {
            g->containsDynamic(hasdynamic);
        }
    };
 
 
    int inside(const EGS_Vector &x) {
        return isWhere(x);
    };
 
    int medium(int ireg) const {
        if (ireg < nbase) {
            return g->medium(ireg);
        }
        int jg = (ireg - nbase)/nmax;
        int ilocal = ireg - nbase - jg*nmax;
        return geometries[jg]->medium(ilocal);
    };
 
    int computeIntersections(int ireg, int n, const EGS_Vector &X,
                             const EGS_Vector &u, EGS_GeometryIntersections *isections) {
        if (n < 1) {
            return -1;
        }
        int ifirst = 0;
        EGS_Float t, ttot = 0;
        EGS_Vector x(X);
        int imed;
        //egsInformation("computeIntersections: ireg=%d x=(%g,%g,%g) "
        //     "u=(%g,%g,%g)\n",ireg,x.x,x.y,x.z,u.x,u.y,u.z);
        if (ireg < 0) {
            t = veryFar;
            ireg = howfar(ireg,x,u,t,&imed);
            if (ireg < 0) {
                return 0;
            }
            isections[0].t = t;
            isections[0].rhof = 1;
            isections[0].ireg = -1;
            isections[0].imed = -1;
            ttot = t;
            ++ifirst;
            x += u*t;
            //egsInformation("entered after t=%g in ireg=%d at x=(%g,%g,%g)\n",
            //        t,ireg,x.x,x.y,x.z);
        }
        else {
            imed = medium(ireg);
        }
 
 
        int j = ifirst;
        int ij = -1, ig=0;
        for (EGS_I64 loopCount=0; loopCount<=loopMax; ++loopCount) {
            if (loopCount == loopMax) {
                egsFatal("EGS_FastEnvelope::computeIntersections: Too many iterations were required! Input may be invalid, or consider increasing loopMax.");
                return -1;
            }
            //egsInformation("in loop: j=%d ireg=%d imed=%d x=(%g,%g,%g)\n",
            //        j,ireg,imed,x.x,x.y,x.z);
            if (ireg >= nbase) {
                ig = (ireg - nbase)/nmax;
                ij = ireg - nbase - ig*nmax;
            }
            isections[j].imed = imed;
            isections[j].ireg = ireg;
            isections[j].rhof = getRelativeRho(ireg);
            if (ireg < nbase) { // in one of the regions of the base geometry
                t = veryFar;
                int ibase = g->howfar(ireg,x,u,t,&imed);
                //egsInformation("In base geometry: t=%g inew=%d\n",t,ibase);
                ij = -1;
                for (int ii=n_start[ireg]; ii<n_start[ireg+1]; ii++) {
                    int i = glist[ii];
                    int ireg_i = geometries[i]->howfar(-1,x,u,t,&imed);
                    if (ireg_i >= 0) {
                        ij = ireg_i;
                        ig = i;
                    }
                }
                ttot += t;
                isections[j++].t = ttot;
                //egsInformation("after inscribed loop: t=%g ij=%d ig=%d"
                //      " ttot=%g\n",t,ij,ig,ttot);
                if (ij < 0) {
                    ireg = ibase;
                }
                else {
                    ireg = nbase + ig*nmax + ij;
                }
                if (ireg < 0) {
                    return j;
                }
                if (j >= n) {
                    return -1;
                }
                x += u*t;
            }
            else {
                int iadd = nbase + ig*nmax;
                int nsec = geometries[ig]->computeIntersections(ij,n-j,
                           x,u,&isections[j]);
                //egsInformation("In inscribed %d: got %d intersections\n",ig,
                //        nsec);
                int nm = nsec >= 0 ? nsec+j : n;
                for (int i=j; i<nm; i++) {
                    isections[i].ireg += iadd;
                    isections[i].t += ttot;
                }
                //egsInformation("last intersection: %g\n",isections[nm-1].t);
                if (nsec < 0) {
                    return nsec;
                }
                j += nsec;
                if (j >= n) {
                    return -1;
                }
                t = isections[j-1].t - ttot;
                x += u*t;
                ttot = isections[j-1].t;
                ireg = g->isWhere(x);
                //egsInformation("new region: %d\n",ireg);
                if (ireg < 0) {
                    return j;
                }
                imed = g->medium(ireg);
            }
        }
        return -1;
    }
 
    EGS_Float howfarToOutside(int ireg, const EGS_Vector &x,
                              const EGS_Vector &u) {
        if (ireg < 0) {
            return 0;
        }
        EGS_Float d;
        if (ireg < nbase) {
            d = g->howfarToOutside(ireg,x,u);
        }
        else if (g->regions() == 1) {
            d = g->howfarToOutside(0,x,u);
        }
        else {
            int ir = g->isWhere(x);
            d = g->howfarToOutside(ir,x,u);
        }
        return d;
    };
 
    int howfar(int ireg, const EGS_Vector &x, const EGS_Vector &u,
               EGS_Float &t, int *newmed = 0, EGS_Vector *normal = 0) {
        if (ireg >= 0) {
            // inside.
            if (ireg < nbase) {
                // in one of the regions of the base geometry
                // check if we hit a boundary in the base geometry.
                // if we do, newmed and normal get set accordingly.
                int ibase = g->howfar(ireg,x,u,t,newmed,normal);
                int ij = -1, jg;
                // check if we will enter any of the inscribed geometries
                // before entering a new region in the base geometry.
                for (int jj=n_start[ireg]; jj<n_start[ireg+1]; jj++) {
                    int j = glist[jj];
                    int ireg_j =
                        geometries[j]->howfar(-1,x,u,t,newmed,normal);
                    if (ireg_j >= 0) {
                        // we do. remember the inscribed geometry index
                        // and local region
                        ij = ireg_j;
                        jg = j;
                    }
                }
                if (ij < 0) {
                    return ibase;
                }
                // ij<0 implies that we have not hit any of the
                // inscribed geometries => return the base geometry index.
                // ij>=0 implies that we entered inscribed geometry
                // jg in its local region ij.
                return nbase + jg*nmax + ij;
            }
            // if here, we are in an inscribed geometry.
            // calculate its index (jg) and its local region (ilocal).
            int jg = (ireg - nbase)/nmax;
            int ilocal = ireg - nbase - jg*nmax;
            // and then check if we will hit a boundary in this geometry.
            int inew = geometries[jg]->howfar(ilocal,x,u,t,newmed,normal);
            if (inew >= 0) {
                return nbase + jg*nmax + inew;
            }
            // inew >= 0 implies that we either stay in the same
            // region (inew=ilocal) or we entered a new region
            // (inew!=ilocal), which is still inside the inscribed geometry
            // inew<0 implies that we have exited the inscribed geometry
            // => check to see in which base geometry region we are.
            inew = g->isWhere(x+u*t);
            if (inew >= 0 && newmed) {
                *newmed = g->medium(inew);
            }
            return inew;
        }
        // if here, we are outside the base geometry.
        // check to see if we will enter.
        int ienter = g->howfar(ireg,x,u,t,newmed,normal);
        if (ienter >= 0) {
            // yes, we do. see if we are already inside of one of the
            // inscribed geometries.
            //if( n_start[ienter] < 0 ) return ienter;
            for (int jj=n_start[ienter]; jj<n_start[ienter+1]; jj++) {
                int j = glist[jj];
                int i = geometries[j]->isWhere(x+u*t);
                if (i >= 0) {
                    // yes, we are.
                    if (newmed) {
                        *newmed = geometries[j]->medium(i);
                    }
                    return nbase + nmax*j + i;
                }
            }
        }
        return ienter;
    };
 
    EGS_Float hownear(int ireg, const EGS_Vector &x) {
        if (ireg >= 0) {
            EGS_Float tmin;
            if (ireg < nbase) {  // in one of the regions of the base geom.
                tmin = g->hownear(ireg,x);
                if (tmin <= 0) {
                    return tmin;
                }
                for (int jj=n_start[ireg]; jj<n_start[ireg+1]; jj++) {
                    int j = glist[jj];
                    EGS_Float tj = geometries[j]->hownear(-1,x);
                    if (tj < tmin) {
                        tmin = tj;
                        if (tmin <= 0) {
                            return tmin;
                        }
                    }
                }
                return tmin;
            }
            int jg = (ireg - nbase)/nmax;
            int ilocal = ireg - nbase - jg*nmax;
            return geometries[jg]->hownear(ilocal,x);
        }
        return g->hownear(ireg,x);
    };
 
    bool hasBooleanProperty(int ireg, EGS_BPType prop) const {
        if (ireg >= 0 && ireg < nreg) {
            if (ireg < nbase) {
                return g->hasBooleanProperty(ireg,prop);
            }
            int jg = (ireg - nbase)/nmax;
            int ilocal = ireg - nbase - jg*nmax;
            return geometries[jg]->hasBooleanProperty(ilocal,prop);
        }
        return false;
    };
    void setBooleanProperty(EGS_BPType) {
        setPropertyError("setBooleanProperty()");
    };
    void addBooleanProperty(int) {
        setPropertyError("addBooleanProperty()");
    };
    void setBooleanProperty(EGS_BPType,int,int,int step=1) {
        setPropertyError("setBooleanProperty()");
    };
    void addBooleanProperty(int,int,int,int step=1) {
        setPropertyError("addBooleanProperty()");
    };
 
    int getMaxStep() const {
        int nstep = g->getMaxStep();
        for (int j=0; j<n_in; ++j) {
            nstep += geometries[j]->getMaxStep();
        }
        return nstep+n_in;
    };
 
    const string &getType() const {
        return type;
    };
 
    void printInfo() const;
 
    void setRelativeRho(int start, int end, EGS_Float rho);
    void setRelativeRho(EGS_Input *);
    EGS_Float getRelativeRho(int ireg) const {
        if (ireg < 0 || ireg >= nreg) {
            return 1;
        }
        if (ireg < nbase) {
            return g->getRelativeRho(ireg);
        }
        int jg = (ireg - nbase)/nmax;
        return geometries[jg]->getRelativeRho(ireg - nbase - jg*nmax);
    };
 
    void setBScaling(int start, int end, EGS_Float bf);
    void setBScaling(EGS_Input *);
    EGS_Float getBScaling(int ireg) const {
        if (ireg < 0 || ireg >= nreg) {
            return 1;
        }
        if (ireg < nbase) {
            return g->getBScaling(ireg);
        }
        int jg = (ireg - nbase)/nmax;
        return geometries[jg]->getBScaling(ireg - nbase - jg*nmax);
    };
 
    virtual void getLabelRegions(const string &str, vector<int> &regs);
 
protected:
 
    EGS_BaseGeometry *g;           
    EGS_BaseGeometry **geometries; 
    int              n_in;         
    int              nbase,   
                     nmax;    
    int              *glist;
    int              *n_start;
    static string    type;    
 
    bool new_indexing;        
    int *reg_to_inscr;        
    int *local_start;         
 
    void setMedia(EGS_Input *,int,const int *);
 
private:
 
    void setPropertyError(const char *funcname) {
        egsFatal("EGS_FastEnvelope::%s: don't use this method\n  Define "
                 "properties in the constituent geometries instead\n",
                 funcname);
    };
 
 
};
 
#endif