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geant4/source/geometry/solids/CSG/src/G4Torus.cc
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2016-06-08 15:34:16 +02:00

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// This code implementation is the intellectual property of
// the GEANT4 collaboration.
//
// By copying, distributing or modifying the Program (or any work
// based on the Program) you indicate your acceptance of this statement,
// and all its terms.
//
// $Id: G4Torus.cc,v 1.4 1999/12/15 14:50:07 gunter Exp $
// GEANT4 tag $Name: geant4-01-01 $
//
//
// class G4Torus
//
// Implementation
//
// 30.10.96 V. Grichine First implementation with G4Tubs elements in Fs
// 09.10.98 V. Grichine modifications in Distance ToOut(p,v,...)
// 19.11.99 V. Grichine side = kNull in Distance ToOut(p,v,...)
#include "G4Torus.hh"
#include "G4VoxelLimits.hh"
#include "G4AffineTransform.hh"
#include "G4VPVParameterisation.hh"
#include "meshdefs.hh"
#include "G4VGraphicsScene.hh"
#include "G4Polyhedron.hh"
#include "G4NURBS.hh"
#include "G4NURBStube.hh"
#include "G4NURBScylinder.hh"
#include "G4NURBStubesector.hh"
#include "G4VisExtent.hh"
///////////////////////////////////////////////////////////////
//
// Constructor - check parameters, convert angles so 0<sphi+dpshi<=2_PI
// - note if pdphi>2PI then reset to 2PI
G4Torus::G4Torus(const G4String &pName,
G4double pRmin,
G4double pRmax,
G4double pRtor,
G4double pSPhi,
G4double pDPhi)
: G4CSGSolid(pName)
{
SetAllParameters(pRmin, pRmax, pRtor, pSPhi, pDPhi);
}
void
G4Torus::SetAllParameters(
G4double pRmin,
G4double pRmax,
G4double pRtor,
G4double pSPhi,
G4double pDPhi)
{
// Check swept radius
if (pRtor>=pRmax)
{
fRtor=pRtor;
}
else
{
G4Exception("Error in G4Torus::SetAllParameters - invalid swept radius");
}
// Check radii
if (pRmin<pRmax&&pRmin>=0)
{
fRmin=pRmin; fRmax=pRmax;
}
else
{
G4Exception("Error in G4Torus::SetAllParameters - invalid radii");
}
// Check angles
if (pDPhi>=2.0*M_PI)
{
fDPhi=2*M_PI;
}
else
{
if (pDPhi>0)
{
fDPhi = pDPhi;
}
else
{
G4Exception("Error in G4Torus::SetAllParameters - invalid dphi");
}
}
// Ensure psphi in 0-2PI or -2PI-0 range if shape crosses 0
fSPhi = pSPhi;
if (fSPhi<0)
{
fSPhi=2.0*M_PI-fmod(fabs(fSPhi),2.0*M_PI);
}
else
{
fSPhi=fmod(fSPhi,2.0*M_PI);
}
if (fSPhi+fDPhi>2.0*M_PI)
{
fSPhi-=2.0*M_PI;
}
}
//////////////////////////////////////////////////////////////////////
//
// Destructor
G4Torus::~G4Torus()
{;}
//////////////////////////////////////////////////////////////////////
//
// Dispatch to parameterisation for replication mechanism dimension
// computation & modification.
void G4Torus::ComputeDimensions(G4VPVParameterisation* p,
const G4int n,
const G4VPhysicalVolume* pRep)
{
p->ComputeDimensions(*this,n,pRep);
}
///////////////////////////////////////////////////////////////////////////
//
// Test function for study of intersections of a ray (starting from p along
// v) with the torus
G4int G4Torus::TorusRoots( G4double Ri,
const G4ThreeVector& p,
const G4ThreeVector& v) const
{
// Define roots Si (generally real >=0) for intersection with
// torus (Ri = fRmax or fRmin) of ray p +S*v . General equation is :
// c[4]*S^4 + c[3]*S^3 +c[2]*S^2 + c[1]*S + c[0] = 0 .
G4double c[5],s[4] ;
G4int num, i, j ;
G4double pDotV = p.x()*v.x() + p.y()*v.y() + p.z()*v.z() ;
G4double pRad2 = p.x()*p.x() + p.y()*p.y() + p.z()*p.z() ;
G4double Rtor2 = fRtor*fRtor, Ri2 = Ri*Ri ;
c[4] = 1.0 ;
c[3] = 4*pDotV ;
c[2] = 2*(pRad2 + 2*pDotV*pDotV - Rtor2 - Ri2 + 2*Rtor2*v.z()*v.z()) ;
c[1] = 4*(pDotV*(pRad2-Rtor2-Ri2) + 2*Rtor2*p.z()*v.z()) ;
c[0] = pRad2*pRad2 - 2*pRad2*(Rtor2+Ri2)
+ 4*Rtor2*p.z()*p.z() + (Rtor2-Ri2)*(Rtor2-Ri2) ;
num = SolveBiQuadratic(c,s) ;
if(num)
{
for(i=0;i<num;i++) // leave only >=0 roots
{
if(s[i]<0)
{
for(j=i+1;j<num;j++) s[j-1] = s[j] ;
i-- ;
num-- ;
}
}
if(num)
{
for(i=0;i<num;i++)
{
G4cout<<i<<" Root = "<<s[i]<<G4endl ;
}
}
else G4cout<<"All real roots are negative"<<G4endl ;
}
else G4cout<<"No real roots for intesection with torus"<<G4endl;
return num ;
}
/////////////////////////////////////////////////////////////////////////
//
// Auxiliary method for solving (in real numbers) biquadratic equation
// Algorithm based on : Graphics Gems I by Jochen Schwartz
G4int G4Torus::SolveBiQuadratic(double c[], double s[] ) const
{
G4double coeffs[ 4 ];
G4double z, u, v, sub;
G4double A, B, C, D;
G4double A2, p, q, r;
G4int i,j, num;
// normal form: x^4 + Ax^3 + Bx^2 + Cx + D = 0
A = c[ 3 ]; // c[ 4 ]; since always c[4]==1 !
B = c[ 2 ]; // c[ 4 ];
C = c[ 1 ]; // c[ 4 ];
D = c[ 0 ]; // c[ 4 ];
// substitute x = y - A/4 to eliminate cubic term:
// y^4 + py^2 + qy + r = 0
A2 = A*A;
p = - 0.375*A2 + B;
q = 0.125*A2*A - 0.5*A*B + C;
r = - 3.0/256*A2*A2 + 1.0/16*A2*B - 0.25*A*C + D;
// y^4 + py^2 + r = 0 and z=y^2 so y = +-sqrt(z1) and y = +-sqrt(z2)
if(q==0)
{
coeffs[ 0 ] = r;
coeffs[ 1 ] = p;
coeffs[ 2 ] = 1;
num = SolveQuadratic(coeffs, s) ;
if(num)
{
if(num==2)
{
if(s[0]>=0)
{
if(s[0]==0) // Three roots and one of them == 0
{
s[2] = sqrt(s[1]) ;
s[1] = s[0] ;
s[0] = -s[2] ;
num++ ;
}
else // Four roots
{
s[2] = sqrt(s[0]) ;
s[3] = sqrt(s[1]) ;
s[0] = -s[3] ;
s[1] = -s[2] ;
num +=2 ;
}
}
else if(s[1]>=0)
{
if(s[1]==0) // One root == 0
{
s[0] = 0 ;
num--;
}
else // Two roots
{
s[0] = -sqrt(s[1]) ;
s[1] = -s[0] ;
}
}
else return num = 0 ; // Both Quadratic roots are negative
}
else // num = 1 two equal roots from SolveQuadratic
{
if(s[0]>=0)
{
if(s[0]==0) ;
else
{
s[1] = sqrt(s[0]) ;
s[0] = -s[1] ;
num +=1 ;
}
}
else return num = 0 ;
}
}
else return num ;
}
else if (r==0) // no absolute term: y(y^3 + py + q) = 0
{
coeffs[ 0 ] = q;
coeffs[ 1 ] = p;
coeffs[ 2 ] = 0;
coeffs[ 3 ] = 1;
num = SolveCubic(coeffs, s);
s[ num++ ] = 0;
for(j=1;j<num;j++) // picksort of roots in ascending order
{
sub = s[j] ;
i=j-1 ;
while(i>=0 && s[i]>sub)
{
s[i+1] = s[i--] ;
}
s[i+1] = sub ;
}
}
else
{
// solve the resolvent cubic ...
coeffs[ 0 ] = 0.5*r*p - 0.125*q*q;
coeffs[ 1 ] = - r;
coeffs[ 2 ] = - 0.5*p;
coeffs[ 3 ] = 1;
num = SolveCubic(coeffs, s);
// ... and take the one real solution ...
z = s[ 0 ];
// ... to Build two quadratic equations
u = z * z - r;
v = 2 * z - p;
if (u==0) u = 0 ;
else if (u > 0) u = sqrt(u) ;
else return 0 ;
if (v==0) v = 0 ;
else if (v > 0) v = sqrt(v);
else return 0 ;
coeffs[ 0 ] = z - u;
coeffs[ 1 ] = q < 0 ? -v : v;
coeffs[ 2 ] = 1;
num = SolveQuadratic(coeffs, s);
coeffs[ 0 ]= z + u;
coeffs[ 1 ] = q < 0 ? v : -v;
coeffs[ 2 ] = 1;
num += SolveQuadratic(coeffs, s + num);
}
// resubstitute
sub = 1.0/4 * A;
for (i = 0; i < num; ++i)
s[ i ] -= sub;
return num;
}
/////////////////////////////////////////////////////////////////////////////
//
// Auxiliary method for solving of cubic equation in real numbers
// From Graphics Gems I bu Jochen Schwartz
G4int G4Torus::SolveCubic(double c[], double s[] ) const
{
G4int i, num;
G4double sub;
G4double A, B, C;
G4double A2, p, q;
G4double p3, D;
// normal form: x^3 + Ax^2 + Bx + C = 0
A = c[ 2 ]; // c[ 3 ]; since always c[3]==1 !
B = c[ 1 ]; // c[ 3 ];
C = c[ 0 ]; // c[ 3 ];
// substitute x = y - A/3 to eliminate quadric term:
// x^3 +px + q = 0
A2 = A*A;
p = 1.0/3*(- 1.0/3*A2 + B);
q = 1.0/2*(2.0/27*A*A2 - 1.0/3*A*B + C);
// use Cardano's formula
p3 = p*p*p;
D = q*q + p3;
if (D==0)
{
if (q==0) // one triple solution
{
s[ 0 ] = 0;
num = 1;
}
else // one single and one double solution
{
G4double u = cbrt(-q);
s[ 0 ] = 2 * u;
s[ 1 ] = - u;
num = 2;
}
}
else if (D < 0) // Casus irreducibilis: three real solutions
{
G4double phi = 1.0/3 * acos(-q / sqrt(-p3));
G4double t = 2 * sqrt(-p);
s[ 0 ] = t * cos(phi);
s[ 1 ] = - t * cos(phi + M_PI / 3);
s[ 2 ] = - t * cos(phi - M_PI / 3);
num = 3;
}
else // one real solution
{
G4double sqrt_D = sqrt(D);
G4double u = cbrt(sqrt_D - q);
G4double v = - cbrt(sqrt_D + q);
s[ 0 ] = u + v;
num = 1;
}
// resubstitute
sub = 1.0/3 * A;
for (i = 0; i < num; ++i)
s[ i ] -= sub;
return num;
}
///////////////////////////////////////////////////////////////////////////
//
// Auxiliary method for solving quadratic equations in real numbers
// From Graphics Gems I by Jochen Schwartz
G4int G4Torus::SolveQuadratic(double c[], double s[] ) const
{
G4double p, q, D;
// normal form: x^2 + px + q = 0
p = c[ 1 ]/2 ; // * c[ 2 ]); since always c[2]==1
q = c[ 0 ] ; // c[ 2 ];
D = p * p - q;
if (D==0)
{
s[ 0 ] = - p; // Generally we have two equal roots ?!
return 1; // But consider them as one for geometry
}
else if (D > 0)
{
G4double sqrt_D = sqrt(D);
s[ 0 ] = - p - sqrt_D ; // in ascending order !
s[ 1 ] = - p + sqrt_D ;
return 2;
}
return 0;
}
/////////////////////////////////////////////////////////////////////////////
//
// Calculate extent under transform and specified limit
G4bool G4Torus::CalculateExtent(const EAxis pAxis,
const G4VoxelLimits& pVoxelLimit,
const G4AffineTransform& pTransform,
G4double& pMin, G4double& pMax) const
{
if (!pTransform.IsRotated()&&fDPhi==2.0*M_PI&&fRmin==0)
{
// Special case handling for unrotated solid torus
// Compute x/y/z mins and maxs for bounding box respecting limits,
// with early returns if outside limits. Then switch() on pAxis,
// and compute exact x and y limit for x/y case
G4double xoffset,xMin,xMax;
G4double yoffset,yMin,yMax;
G4double zoffset,zMin,zMax;
G4double diff1,diff2,maxDiff,newMin,newMax;
G4double xoff1,xoff2,yoff1,yoff2;
xoffset=pTransform.NetTranslation().x();
xMin=xoffset-fRmax-fRtor;
xMax=xoffset+fRmax+fRtor;
if (pVoxelLimit.IsXLimited())
{
if (xMin>pVoxelLimit.GetMaxXExtent()+kCarTolerance
||xMax<pVoxelLimit.GetMinXExtent()-kCarTolerance)
{
return false;
}
else
{
if (xMin<pVoxelLimit.GetMinXExtent())
{
xMin=pVoxelLimit.GetMinXExtent();
}
if (xMax>pVoxelLimit.GetMaxXExtent())
{
xMax=pVoxelLimit.GetMaxXExtent();
}
}
}
yoffset=pTransform.NetTranslation().y();
yMin=yoffset-fRmax-fRtor;
yMax=yoffset+fRmax+fRtor;
if (pVoxelLimit.IsYLimited())
{
if (yMin>pVoxelLimit.GetMaxYExtent()+kCarTolerance
||yMax<pVoxelLimit.GetMinYExtent()-kCarTolerance)
{
return false;
}
else
{
if (yMin<pVoxelLimit.GetMinYExtent())
{
yMin=pVoxelLimit.GetMinYExtent();
}
if (yMax>pVoxelLimit.GetMaxYExtent())
{
yMax=pVoxelLimit.GetMaxYExtent();
}
}
}
zoffset=pTransform.NetTranslation().z();
zMin=zoffset-fRmax;
zMax=zoffset+fRmax;
if (pVoxelLimit.IsZLimited())
{
if (zMin>pVoxelLimit.GetMaxZExtent()+kCarTolerance
||zMax<pVoxelLimit.GetMinZExtent()-kCarTolerance)
{
return false;
}
else
{
if (zMin<pVoxelLimit.GetMinZExtent())
{
zMin=pVoxelLimit.GetMinZExtent();
}
if (zMax>pVoxelLimit.GetMaxZExtent())
{
zMax=pVoxelLimit.GetMaxZExtent();
}
}
}
// Known to cut cylinder
switch (pAxis)
{
case kXAxis:
yoff1=yoffset-yMin;
yoff2=yMax-yoffset;
if (yoff1>=0&&yoff2>=0)
{
// Y limits cross max/min x => no change
pMin=xMin;
pMax=xMax;
}
else
{
// Y limits don't cross max/min x => compute max delta x, hence new mins/maxs
diff1=sqrt(fRmax*fRmax-yoff1*yoff1);
diff2=sqrt(fRmax*fRmax-yoff2*yoff2);
maxDiff=(diff1>diff2) ? diff1:diff2;
newMin=xoffset-maxDiff;
newMax=xoffset+maxDiff;
pMin=(newMin<xMin) ? xMin : newMin;
pMax=(newMax>xMax) ? xMax : newMax;
}
break;
case kYAxis:
xoff1=xoffset-xMin;
xoff2=xMax-xoffset;
if (xoff1>=0&&xoff2>=0)
{
// X limits cross max/min y => no change
pMin=yMin;
pMax=yMax;
}
else
{
// X limits don't cross max/min y => compute max delta y, hence new mins/maxs
diff1=sqrt(fRmax*fRmax-xoff1*xoff1);
diff2=sqrt(fRmax*fRmax-xoff2*xoff2);
maxDiff=(diff1>diff2) ? diff1:diff2;
newMin=yoffset-maxDiff;
newMax=yoffset+maxDiff;
pMin=(newMin<yMin) ? yMin : newMin;
pMax=(newMax>yMax) ? yMax : newMax;
}
break;
case kZAxis:
pMin=zMin;
pMax=zMax;
break;
}
pMin-=kCarTolerance;
pMax+=kCarTolerance;
return true;
}
else
{
G4int i,noEntries,noBetweenSections4;
G4bool existsAfterClip=false;
// Calculate rotated vertex coordinates
G4ThreeVectorList *vertices;
G4int noPolygonVertices ; // will be 4
vertices=CreateRotatedVertices(pTransform,noPolygonVertices);
pMin=+kInfinity;
pMax=-kInfinity;
noEntries=vertices->entries();
noBetweenSections4=noEntries-noPolygonVertices;
for (i=0;i<noEntries;i+=noPolygonVertices)
{
ClipCrossSection(vertices,i,pVoxelLimit,pAxis,pMin,pMax);
}
for (i=0;i<noBetweenSections4;i+=noPolygonVertices)
{
ClipBetweenSections(vertices,i,pVoxelLimit,pAxis,pMin,pMax);
}
if (pMin!=kInfinity||pMax!=-kInfinity)
{
existsAfterClip=true;
// Add 2*tolerance to avoid precision troubles
pMin-=kCarTolerance;
pMax+=kCarTolerance;
}
else
{
// Check for case where completely enveloping clipping volume
// If point inside then we are confident that the solid completely
// envelopes the clipping volume. Hence set min/max extents according
// to clipping volume extents along the specified axis.
G4ThreeVector clipCentre(
(pVoxelLimit.GetMinXExtent()+pVoxelLimit.GetMaxXExtent())*0.5,
(pVoxelLimit.GetMinYExtent()+pVoxelLimit.GetMaxYExtent())*0.5,
(pVoxelLimit.GetMinZExtent()+pVoxelLimit.GetMaxZExtent())*0.5);
if (Inside(pTransform.Inverse().TransformPoint(clipCentre))!=kOutside)
{
existsAfterClip=true;
pMin=pVoxelLimit.GetMinExtent(pAxis);
pMax=pVoxelLimit.GetMaxExtent(pAxis);
}
}
delete vertices;
return existsAfterClip;
}
}
////////////////////////////////////////////////////////////////////////////////
//
// Return whether point inside/outside/on surface
EInside G4Torus::Inside(const G4ThreeVector& p) const
{
G4double r2,pt2,pPhi,tolRMin,tolRMax;
EInside in=kOutside;
// General precals
r2=p.x()*p.x()+p.y()*p.y();
pt2 = r2+p.z()*p.z() +fRtor*fRtor - 2*fRtor*sqrt(r2) ;
if (fRmin) tolRMin=fRmin+kRadTolerance*0.5;
else tolRMin=0;
tolRMax=fRmax-kRadTolerance*0.5;
if (pt2>=tolRMin*tolRMin && pt2<=tolRMax*tolRMax)
{
if (fDPhi==2*M_PI||pt2==0) // on torus swept axis
{
in=kInside;
}
else
{
// Try inner tolerant phi boundaries (=>inside)
// if not inside, try outer tolerant phi boundaries
pPhi=atan2(p.y(),p.x());
if (pPhi<0) pPhi+=2*M_PI; // 0<=pPhi<2*M_PI
if (fSPhi>=0)
{
if (pPhi>=fSPhi+kAngTolerance*0.5 &&
pPhi<=fSPhi+fDPhi-kAngTolerance*0.5)
{
in=kInside;
}
else if (pPhi>=fSPhi-kAngTolerance*0.5 &&
pPhi<=fSPhi+fDPhi+kAngTolerance*0.5)
{
in=kSurface;
}
}
else
{
if (pPhi<fSPhi+2*M_PI) pPhi+=2*M_PI;
if (pPhi>=fSPhi+2*M_PI+kAngTolerance*0.5 &&
pPhi<=fSPhi+fDPhi+2*M_PI-kAngTolerance*0.5)
{
in=kInside;
}
else if (pPhi>=fSPhi+2*M_PI-kAngTolerance*0.5 &&
pPhi<=fSPhi+fDPhi+2*M_PI+kAngTolerance*0.5)
{
in=kSurface;
}
}
}
}
else
{
// Try generous boundaries
tolRMin=fRmin-kRadTolerance*0.5;
tolRMax=fRmax+kRadTolerance*0.5;
if (tolRMin<0) tolRMin=0;
if (pt2>=tolRMin*tolRMin && pt2 <= tolRMax*tolRMax)
{
if (fDPhi==2*M_PI||pt2==0)
{
// Continuous in phi or on z-axis
in=kSurface;
}
else
{
// Try outer tolerant phi boundaries only
pPhi=atan2(p.y(),p.x());
if (pPhi<0) pPhi+=2*M_PI; // 0<=pPhi<2*M_PI
if (fSPhi>=0)
{
if (pPhi>=fSPhi-kAngTolerance*0.5 &&
pPhi<=fSPhi+fDPhi+kAngTolerance*0.5)
{
in=kSurface;
}
}
else
{
if (pPhi<fSPhi+2*M_PI) pPhi+=2*M_PI;
if (pPhi>=fSPhi+2*M_PI-kAngTolerance*0.5 &&
pPhi<=fSPhi+fDPhi+2*M_PI+kAngTolerance*0.5)
{
in=kSurface;
}
}
}
}
}
return in;
}
/////////////////////////////////////////////////////////////////////////////
//
// Return unit normal of surface closest to p
// - note if point on z axis, ignore phi divided sides
// - unsafe if point close to z axis a rmin=0 - no explicit checks
G4ThreeVector G4Torus::SurfaceNormal( const G4ThreeVector& p) const
{
ENorm side;
G4ThreeVector norm;
G4double rho2,rho,pt2,pt,phi;
G4double distRMin,distRMax,distSPhi,distEPhi,distMin;
rho2 = p.x()*p.x() + p.y()*p.y();
rho = sqrt(rho2) ;
pt2 = fabs(rho2+p.z()*p.z() +fRtor*fRtor - 2*fRtor*rho) ;
pt = sqrt(pt2) ;
distRMax=fabs(pt-fRmax);
// First minimum
if(fRmin)
{
distRMin=fabs(pt-fRmin);
if (distRMin<distRMax)
{
distMin=distRMin;
side=kNRMin;
}
else
{
distMin=distRMax;
side=kNRMax;
}
}
else
{
distMin=distRMax;
side=kNRMax;
}
if (fDPhi<2.0*M_PI&&rho)
{
// Protected against (0,0,z) (above)
phi=atan2(p.y(),p.x());
if (phi<0) phi+=2*M_PI;
if (fSPhi<0)
{
distSPhi=fabs(phi-(fSPhi+2.0*M_PI))*rho;
}
else
{
distSPhi=fabs(phi-fSPhi)*rho;
}
distEPhi=fabs(phi-fSPhi-fDPhi)*rho;
// Find new minimum
if (distSPhi<distEPhi)
{
if (distSPhi<distMin)
{
side=kNSPhi;
}
}
else
{
if (distEPhi<distMin)
{
side=kNEPhi;
}
}
}
switch (side)
{
case kNRMin: // Inner radius
norm=G4ThreeVector(-p.x()*(1-fRtor/rho)/pt,
-p.y()*(1-fRtor/rho)/pt,
-p.z()/pt);
break;
case kNRMax: // Outer radius
norm=G4ThreeVector(p.x()*(1-fRtor/rho)/pt,
p.y()*(1-fRtor/rho)/pt,
p.z()/pt);
break;
case kNSPhi:
norm=G4ThreeVector(sin(fSPhi),-cos(fSPhi),0);
break;
case kNEPhi:
norm=G4ThreeVector(-sin(fSPhi+fDPhi),cos(fSPhi+fDPhi),0);
break;
default:
G4Exception("Logic error in G4Torus::SurfaceNormal");
break;
} // end case
return norm;
}
///////////////////////////////////////////////////////////////////////
//
// Calculate distance to shape from outside, along normalised vector
// - return kInfinity if no intersection, or intersection distance <= tolerance
//
// - Compute the intersection with the z planes
// - if at valid r, phi, return
//
// -> If point is outer outer radius, compute intersection with rmax
// - if at valid phi,z return
//
// -> Compute intersection with inner radius, taking largest +ve root
// - if valid (phi), save intersction
//
// -> If phi segmented, compute intersections with phi half planes
// - return smallest of valid phi intersections and
// inner radius intersection
//
// NOTE:
// - Precalculations for phi trigonometry are Done `just in time'
// - `if valid' implies tolerant checking of intersection points
G4double G4Torus::DistanceToIn(const G4ThreeVector& p,
const G4ThreeVector& v) const
{
G4double snxt=kInfinity, sphi=kInfinity;// snxt = default return value
G4double c[5], s[4] ;
// Precalculated trig for phi intersections - used by r,z intersections to
// check validity
G4bool seg; // true if segmented
G4double hDPhi,hDPhiOT,hDPhiIT,cosHDPhiOT,cosHDPhiIT;
// half dphi + outer tolerance
G4double cPhi,sinCPhi,cosCPhi; // central phi
G4double tolORMin2,tolIRMin2; // `generous' radii squared
G4double tolORMax2,tolIRMax2 ;
G4double Dist,xi,yi,zi,rhoi2,it2,inum,cosPsi; // Intersection point variables
G4double Comp;
G4double cosSPhi,sinSPhi; // Trig for phi start intersect
G4double ePhi,cosEPhi,sinEPhi; // for phi end intersect
//
// Set phi divided flag and precalcs
//
if (fDPhi<2.0*M_PI)
{
seg=true;
hDPhi=0.5*fDPhi; // half delta phi
cPhi=fSPhi+hDPhi;;
hDPhiOT=hDPhi+0.5*kAngTolerance; // outers tol' half delta phi
hDPhiIT=hDPhi-0.5*kAngTolerance;
sinCPhi=sin(cPhi);
cosCPhi=cos(cPhi);
cosHDPhiOT=cos(hDPhiOT);
cosHDPhiIT=cos(hDPhiIT);
}
else
{
seg=false;
}
// Calculate tolerant rmin and rmax
if (fRmin>kRadTolerance)
{
tolORMin2=(fRmin-0.5*kRadTolerance)*(fRmin-0.5*kRadTolerance);
tolIRMin2=(fRmin+0.5*kRadTolerance)*(fRmin+0.5*kRadTolerance);
}
else
{
tolORMin2=0;
tolIRMin2=0;
}
tolORMax2=(fRmax+0.5*kRadTolerance)*(fRmax+0.5*kRadTolerance);
tolIRMax2=(fRmax-kRadTolerance*0.5)*(fRmax-kRadTolerance*0.5);
//
// Intersection with Rmax (possible return) and Rmin (must also check phi)
//
G4int i,j,num ;
G4double Rtor2=fRtor*fRtor, Rmax2=fRmax*fRmax, Rmin2=fRmin*fRmin ;
G4double rho2 = p.x()*p.x()+p.y()*p.y();
G4double rho = sqrt(rho2) ;
G4double pt2 = fabs(rho2+p.z()*p.z() +Rtor2 - 2*fRtor*rho) ;
// G4double pt = sqrt(pt2) ;
G4double pDotV = p.x()*v.x() + p.y()*v.y() + p.z()*v.z() ;
G4double pRad2 = p.x()*p.x() + p.y()*p.y() + p.z()*p.z() ;
G4double vDotNmax = pDotV -fRtor*(v.x()*p.x() + v.y()*p.y())/rho ;
// Inside outer radius :
// check not inside, and heading through tubs (-> 0 to in)
if(pt2<=tolORMax2 && pt2>=tolIRMin2 && vDotNmax<0)
{
if (seg)
{
inum = p.x()*cosCPhi+p.y()*sinCPhi;
cosPsi = inum/rho;
if (cosPsi>=cosHDPhiIT)
{
return snxt = 0;
}
}
else
{
return snxt = 0;
}
}
else // intersection with Rmax torus
{
c[4] = 1.0 ;
c[3] = 4*pDotV ;
c[2] = 2*(pRad2 + 2*pDotV*pDotV - Rtor2 - Rmax2 + 2*Rtor2*v.z()*v.z()) ;
c[1] = 4*(pDotV*(pRad2-Rtor2-Rmax2) + 2*Rtor2*p.z()*v.z()) ;
c[0] = pRad2*pRad2 - 2*pRad2*(Rtor2+Rmax2)
+ 4*Rtor2*p.z()*p.z() + (Rtor2-Rmax2)*(Rtor2-Rmax2) ;
num = SolveBiQuadratic(c,s) ;
if(num)
{
for(i=0;i<num;i++) // leave only >=kRadTolerance/2 roots P?!
{
if(s[i]<kRadTolerance*0.5)
{
for(j=i+1;j<num;j++) s[j-1] = s[j] ;
i-- ;
num-- ;
}
}
if(num)
{
for(i=0;i<num;i++)
{
if (seg) // intersection point must have proper Phi
{
xi=p.x()+s[i]*v.x();
yi=p.y()+s[i]*v.y();
rhoi2=xi*xi+yi*yi;
inum = xi*cosCPhi + yi*sinCPhi;
cosPsi = inum/sqrt(rhoi2);
if (cosPsi>=cosHDPhiIT)
{
snxt = s[i] ;
break ;
}
}
else
{
snxt = s[i] ;
break ;
}
}
}
}
}
if (fRmin) // Possible Rmin intersection
{
// Inside relative to inner radius :
// check not inside, and heading through tubs (-> 0 to in)
if(pt2>=tolORMin2 && pt2<=tolIRMax2 && vDotNmax>0)
{
if (seg)
{
inum = p.x()*cosCPhi+p.y()*sinCPhi;
cosPsi = inum/rho;
if (cosPsi>=cosHDPhiIT)
{
return snxt = 0;
}
}
else
{
return snxt = 0;
}
}
else // intersection with Rmin torus
{
c[4] = 1.0 ;
c[3] = 4*pDotV ;
c[2] = 2*(pRad2 + 2*pDotV*pDotV - Rtor2 - Rmin2
+ 2*Rtor2*v.z()*v.z()) ;
c[1] = 4*(pDotV*(pRad2-Rtor2-Rmin2) + 2*Rtor2*p.z()*v.z()) ;
c[0] = pRad2*pRad2 - 2*pRad2*(Rtor2+Rmin2)
+ 4*Rtor2*p.z()*p.z() + (Rtor2-Rmin2)*(Rtor2-Rmin2) ;
num = SolveBiQuadratic(c,s) ;
if(num)
{
for(i=0;i<num;i++) // leave only >=kRadTolerance/2 roots P?!
{
if(s[i]<kRadTolerance*0.5)
{
for(j=i+1;j<num;j++) s[j-1] = s[j] ;
i-- ;
num-- ;
}
}
if(num)
{
for(i=0;i<num;i++)
{
if (seg) // intersection point must have proper Phi
{
xi=p.x()+s[i]*v.x();
yi=p.y()+s[i]*v.y();
rhoi2=xi*xi+yi*yi;
inum = xi*cosCPhi + yi*sinCPhi;
cosPsi = inum/sqrt(rhoi2);
if (cosPsi>=cosHDPhiIT && s[i]<snxt)
{
snxt = s[i] ;
break ;
}
}
else if(s[i]<snxt)
{
snxt = s[i] ;
break ;
}
}
}
}
}
} // if(Rmin)
//
// Phi segment intersection
//
// o Tolerant of points inside phi planes by up to kCarTolerance*0.5
//
// o NOTE: Large duplication of code between sphi & ephi checks
// -> only diffs: sphi -> ephi, Comp -> -Comp and half-plane
// intersection check <=0 -> >=0
// -> use some form of loop Construct ?
//
if (seg)
{
// First phi surface (`S'tarting phi)
sinSPhi=sin(fSPhi);
cosSPhi=cos(fSPhi);
Comp=v.x()*sinSPhi-v.y()*cosSPhi; // Compnent in outwards normal dirn
if (Comp<0)
{
Dist=(p.y()*cosSPhi-p.x()*sinSPhi);
if (Dist<kCarTolerance*0.5)
{
sphi=Dist/Comp;
if (sphi<snxt)
{
if (sphi<0)
{
sphi=0;
}
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
zi=p.z()+sphi*v.z();
rhoi2=xi*xi+yi*yi;
it2 = fabs(rhoi2+zi*zi +Rtor2 - 2*fRtor*sqrt(rhoi2)) ;
if (it2>=tolORMin2 && it2<=tolORMax2)
{
// r intersection is good - check intersecting with correct half-plane
if ((yi*cosCPhi-xi*sinCPhi)<=0) snxt=sphi;
}
}
}
}
// Second phi surface (`E'nding phi)
ePhi=fSPhi+fDPhi;
sinEPhi=sin(ePhi);
cosEPhi=cos(ePhi);
Comp=-(v.x()*sinEPhi-v.y()*cosEPhi);
// Compnent in outwards normal dirn
if (Comp<0)
{
Dist=-(p.y()*cosEPhi-p.x()*sinEPhi);
if (Dist<kCarTolerance*0.5)
{
sphi=Dist/Comp;
if (sphi<snxt)
{
if (sphi<0)
{
sphi=0;
}
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
zi=p.z()+sphi*v.z();
rhoi2=xi*xi+yi*yi;
it2 = fabs(rhoi2+zi*zi +Rtor2 - 2*fRtor*sqrt(rhoi2)) ;
if (it2>=tolORMin2 && it2<=tolORMax2)
{
// z and r intersections good - check intersecting with correct half-plane
if ((yi*cosCPhi-xi*sinCPhi)>=0) snxt=sphi;
}
}
}
}
} // if(seg)
return snxt;
}
/////////////////////////////////////////////////////////////////////////////
//
// Calculate distance (<= actual) to closest surface of shape from outside
// - Calculate distance to z, radial planes
// - Only to phi planes if outside phi extent
// - Return 0 if point inside
G4double G4Torus::DistanceToIn(const G4ThreeVector& p) const
{
G4double safe,safe1,safe2;
G4double phiC,cosPhiC,sinPhiC,safePhi,ePhi,cosPsi;
G4double rho2,rho,pt2,pt ;
rho2 = p.x()*p.x()+p.y()*p.y();
rho = sqrt(rho2) ;
pt2 = fabs(rho2+p.z()*p.z() +fRtor*fRtor - 2*fRtor*rho) ;
pt = sqrt(pt2) ;
safe1=fRmin-pt;
safe2=pt-fRmax;
if (safe1>safe2) safe=safe1;
else safe=safe2;
if (fDPhi<2.0*M_PI&&rho)
{
phiC=fSPhi+fDPhi*0.5;
cosPhiC=cos(phiC);
sinPhiC=sin(phiC);
// Psi=angle from central phi to point
cosPsi=(p.x()*cosPhiC+p.y()*sinPhiC)/rho;
if (cosPsi<cos(fDPhi*0.5))
{
// Point lies outside phi range
if ((p.y()*cosPhiC-p.x()*sinPhiC)<=0)
{
safePhi=fabs(p.x()*sin(fSPhi)-p.y()*cos(fSPhi));
}
else
{
ePhi=fSPhi+fDPhi;
safePhi=fabs(p.x()*sin(ePhi)-p.y()*cos(ePhi));
}
if (safePhi>safe) safe=safePhi;
}
}
if (safe<0) safe=0;
return safe;
}
///////////////////////////////////////////////////////////////////////////
//
// Calculate distance to surface of shape from `inside', allowing for tolerance
// - Only Calc rmax intersection if no valid rmin intersection
G4double G4Torus::DistanceToOut(const G4ThreeVector& p,
const G4ThreeVector& v,
const G4bool calcNorm,
G4bool *validNorm,
G4ThreeVector *n ) const
{
ESide side = kNull, sidephi ;
G4double snxt=kInfinity, sphi,c[5],s[4];
// Vars for phi intersection
G4double sinSPhi,cosSPhi,ePhi,sinEPhi,cosEPhi;
G4double cPhi,sinCPhi,cosCPhi;
G4double pDistS,compS,pDistE,compE,sphi2,xi,yi,zi,vphi;
// Radial Intersections Defenitions & General Precals
// Define roots Si (generally real >=0) for intersection with
// torus (Ri = fRmax or fRmin) of ray p +S*v . General equation is :
// c[4]*S^4 + c[3]*S^3 +c[2]*S^2 + c[1]*S + c[0] = 0 .
G4int i,j,num ;
G4double Rtor2=fRtor*fRtor, Rmax2=fRmax*fRmax, Rmin2=fRmin*fRmin ;
G4double rho2 = p.x()*p.x()+p.y()*p.y();
G4double rho = sqrt(rho2) ;
G4double pt2 = fabs(rho2+p.z()*p.z() + Rtor2 - 2*fRtor*rho) ;
G4double pt = sqrt(pt2) ;
G4double pDotV = p.x()*v.x() + p.y()*v.y() + p.z()*v.z() ;
G4double pRad2 = p.x()*p.x() + p.y()*p.y() + p.z()*p.z() ;
G4double tolRMax=fRmax-kRadTolerance*0.5;
G4double vDotNmax = pDotV -fRtor*(v.x()*p.x() + v.y()*p.y())/rho ;
G4double pDotxyNmax = (1-fRtor/rho) ;
if(pt2>tolRMax*tolRMax && vDotNmax>=0)
{
// On tolerant boundary & heading outwards (or perpendicular to) outer
// radial surface -> leaving immediately with *n for really convex part only
if (calcNorm && pDotxyNmax>=-kRadTolerance)
{
*n=G4ThreeVector(p.x()*(1-fRtor/rho)/pt,
p.y()*(1-fRtor/rho)/pt,
p.z()/pt);
*validNorm=true;
}
return snxt=0; // Leaving by Rmax immediately
}
else
{ // intersection with Rmax torus
c[4] = 1.0 ;
c[3] = 4*pDotV ;
c[2] = 2*(pRad2 + 2*pDotV*pDotV - Rtor2 - Rmax2 + 2*Rtor2*v.z()*v.z()) ;
c[1] = 4*(pDotV*(pRad2-Rtor2-Rmax2) + 2*Rtor2*p.z()*v.z()) ;
c[0] = pRad2*pRad2 - 2*pRad2*(Rtor2+Rmax2)
+ 4*Rtor2*p.z()*p.z() + (Rtor2-Rmax2)*(Rtor2-Rmax2) ;
num = SolveBiQuadratic(c,s) ;
if(num)
{
for(i=0;i<num;i++) // leave only >=kRadTolerance/2 roots
{
if(s[i]<kRadTolerance*0.5)
{
for(j=i+1;j<num;j++) s[j-1] = s[j] ;
i-- ;
num-- ;
}
}
if(num)
{
snxt = s[0] ;
side = kRMax ;
}
}
// Possible Rmin intersection
if (fRmin)
{
G4double tolRMin=fRmin+kRadTolerance*0.5;
// Leaving via Rmin
// NOTE: SHould use rho-rmin>kRadTolerance*0.5 - avoid sqrt for efficiency
if (pt2<tolRMin*tolRMin && vDotNmax<0)
{
if (calcNorm)
{
*validNorm=false; // Concave surface of the torus
}
return snxt=0; // Leaving by Rmin immediately
}
else
{ // intersection with Rmin torus
c[4] = 1.0 ;
c[3] = 4*pDotV ;
c[2] = 2*(pRad2 + 2*pDotV*pDotV - Rtor2 - Rmin2
+ 2*Rtor2*v.z()*v.z()) ;
c[1] = 4*(pDotV*(pRad2-Rtor2-Rmin2) + 2*Rtor2*p.z()*v.z()) ;
c[0] = pRad2*pRad2 - 2*pRad2*(Rtor2+Rmin2)
+ 4*Rtor2*p.z()*p.z() + (Rtor2-Rmin2)*(Rtor2-Rmin2) ;
num = SolveBiQuadratic(c,s) ;
if(num)
{
for(i=0;i<num;i++) // leave only >=kRadTolerance/2 roots
{
if(s[i]<kRadTolerance*0.5)
{
for(j=i+1;j<num;j++) s[j-1] = s[j] ;
i-- ;
num-- ;
}
}
if(num && s[0]<snxt)
{
snxt = s[0] ;
side = kRMin ;
}
}
}
} // if(Rmin)
}
//
// Phi Intersection
//
if (fDPhi<2.0*M_PI)
{
sinSPhi=sin(fSPhi);
cosSPhi=cos(fSPhi);
ePhi=fSPhi+fDPhi;
sinEPhi=sin(ePhi);
cosEPhi=cos(ePhi);
cPhi=fSPhi+fDPhi*0.5;
sinCPhi=sin(cPhi);
cosCPhi=cos(cPhi);
// Check if on z axis (rho not needed later)
if (p.x()||p.y())
{
// pDist -ve when inside
pDistS=p.x()*sinSPhi-p.y()*cosSPhi;
pDistE=-p.x()*sinEPhi+p.y()*cosEPhi;
// Comp -ve when in direction of outwards normal
compS=-sinSPhi*v.x()+cosSPhi*v.y();
compE=sinEPhi*v.x()-cosEPhi*v.y();
sidephi=kNull;
if (pDistS<=0&&pDistE<=0)
{
// Inside both phi *full* planes
if (compS<0)
{
sphi=pDistS/compS;
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
// Check intersecting with correct half-plane (if not -> no intersect)
if ((yi*cosCPhi-xi*sinCPhi)>=0)
sphi=kInfinity;
else
{
sidephi=kSPhi;
if (pDistS>-kCarTolerance*0.5)
sphi=0;
// Leave by sphi immediately
}
}
else sphi=kInfinity;
if (compE<0)
{
sphi2=pDistE/compE;
// Only check further if < starting phi intersection
if (sphi2<sphi)
{
xi=p.x()+sphi2*v.x();
yi=p.y()+sphi2*v.y();
// Check intersecting with correct half-plane
if ((yi*cosCPhi-xi*sinCPhi)>=0)
{
// Leaving via ending phi
sidephi=kEPhi;
if (pDistE<=-kCarTolerance*0.5)
{
sphi=sphi2;
}
else
{
sphi=0;
}
}
}
}
}
else if (pDistS>=0&&pDistE>=0)
{
// Outside both *full* phi planes
if (pDistS <= pDistE)
{
sidephi = kSPhi ;
}
else
{
sidephi = kEPhi ;
}
if (fDPhi>M_PI)
{
if (compS<0&&compE<0) sphi=0;
else sphi=kInfinity;
}
else
{
// if towards both >=0 then once inside (after error) will remain inside
if (compS>=0&&compE>=0)
{
sphi=kInfinity;
}
else
{
sphi=0;
}
}
}
else if (pDistS>0&&pDistE<0)
{
// Outside full starting plane, inside full ending plane
if (fDPhi>M_PI)
{
if (compE<0)
{
sphi=pDistE/compE;
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
// Check intersection in correct half-plane (if not -> not leaving phi extent)
if ((yi*cosCPhi-xi*sinCPhi)<=0)
{
sphi=kInfinity;
}
else
{
// Leaving via Ending phi
sidephi = kEPhi ;
if (pDistE>-kCarTolerance*0.5)
sphi=0;
}
}
else
{
sphi=kInfinity;
}
}
else
{
if (compS>=0)
{
if (compE<0)
{
sphi=pDistE/compE;
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
// Check intersection in correct half-plane (if not -> remain in extent)
if ((yi*cosCPhi-xi*sinCPhi)<=0)
{
sphi=kInfinity;
}
else
{
// otherwise leaving via Ending phi
sidephi=kEPhi;
}
}
else sphi=kInfinity;
}
else
{
// leaving immediately by starting phi
sidephi=kSPhi;
sphi=0;
}
}
}
else
{
// Must be pDistS<0&&pDistE>0
// Inside full starting plane, outside full ending plane
if (fDPhi>M_PI)
{
if (compS<0)
{
sphi=pDistS/compS;
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
// Check intersection in correct half-plane (if not -> not leaving phi extent)
if ((yi*cosCPhi-xi*sinCPhi)>=0)
{
sphi=kInfinity;
}
else
{
// Leaving via Starting phi
sidephi = kSPhi ;
if (pDistS>-kCarTolerance*0.5)
sphi=0;
}
}
else
{
sphi=kInfinity;
}
}
else
{
if (compE>=0)
{
if (compS<0)
{
sphi=pDistS/compS;
xi=p.x()+sphi*v.x();
yi=p.y()+sphi*v.y();
// Check intersection in correct half-plane (if not -> remain in extent)
if ((yi*cosCPhi-xi*sinCPhi)>=0)
{
sphi=kInfinity;
}
else
{
// otherwise leaving via Starting phi
sidephi=kSPhi;
}
}
else
{
sphi=kInfinity;
}
}
else
{
// leaving immediately by ending
sidephi=kEPhi;
sphi=0;
}
}
}
}
else
{
// On z axis + travel not || to z axis -> if phi of vector direction
// within phi of shape, Step limited by rmax, else Step =0
vphi=atan2(v.y(),v.x());
if (fSPhi<vphi&&vphi<fSPhi+fDPhi)
{
sphi=kInfinity;
}
else
{
sidephi = kSPhi ; // arbitrary
sphi=0;
}
}
// Order intersecttions
if (sphi<snxt)
{
snxt=sphi;
side=sidephi;
}
}
G4double rhoi2,rhoi,it2,it,iDotxyNmax ;
if (calcNorm)
{
switch(side)
{
case kRMax: // n is unit vector
xi=p.x()+snxt*v.x();
yi=p.y()+snxt*v.y();
zi=p.z()+snxt*v.z();
rhoi2 = xi*xi+yi*yi;
rhoi = sqrt(rhoi2) ;
it2 = fabs(rhoi2+zi*zi +fRtor*fRtor - 2*fRtor*rhoi) ;
it = sqrt(it2) ;
iDotxyNmax = (1-fRtor/rhoi) ;
if(iDotxyNmax>=-kRadTolerance)
{ // really convex part of Rmax
*n=G4ThreeVector(xi*(1-fRtor/rhoi)/it,
yi*(1-fRtor/rhoi)/it,
zi/it);
*validNorm=true;
}
else
{
*validNorm=false; // concave-convex part of Rmax
}
break;
case kRMin:
*validNorm=false; // Rmin is concave or concave-convex
break;
case kSPhi:
if (fDPhi<=M_PI)
{
*n=G4ThreeVector(sin(fSPhi),-cos(fSPhi),0);
*validNorm=true;
}
else
{
*validNorm=false;
}
break;
case kEPhi:
if (fDPhi<=M_PI)
{
*n=G4ThreeVector(-sin(fSPhi+fDPhi),cos(fSPhi+fDPhi),0);
*validNorm=true;
}
else
{
*validNorm=false;
}
break;
default:
G4Exception("Invalid enum in G4Torus::DistanceToOut");
break;
}
}
return snxt;
}
/////////////////////////////////////////////////////////////////////////
//
// Calcluate distance (<=actual) to closest surface of shape from inside
G4double G4Torus::DistanceToOut(const G4ThreeVector& p) const
{
G4double safe,safeR1,safeR2;
G4double rho2,rho,pt2,pt ;
G4double safePhi,phiC,cosPhiC,sinPhiC,ePhi;
rho2=p.x()*p.x()+p.y()*p.y();
rho=sqrt(rho2);
pt2 = fabs(rho2+p.z()*p.z() +fRtor*fRtor - 2*fRtor*rho) ;
pt = sqrt(pt2) ;
if (fRmin)
{
safeR1=pt-fRmin;
safeR2=fRmax-pt;
if (safeR1<safeR2)
{
safe=safeR1;
}
else
{
safe=safeR2;
}
}
else
{
safe=fRmax-pt;
}
// Check if phi divided, Calc distances closest phi plane
if (fDPhi<2.0*M_PI)
{
// Above/below central phi of Torus?
phiC=fSPhi+fDPhi*0.5;
cosPhiC=cos(phiC);
sinPhiC=sin(phiC);
if ((p.y()*cosPhiC-p.x()*sinPhiC)<=0)
{
safePhi=-(p.x()*sin(fSPhi)-p.y()*cos(fSPhi));
}
else
{
ePhi=fSPhi+fDPhi;
safePhi=(p.x()*sin(ePhi)-p.y()*cos(ePhi));
}
if (safePhi<safe) safe=safePhi;
}
if (safe<0) safe=0;
return safe;
}
/////////////////////////////////////////////////////////////////////////////
//
// Create a List containing the transformed vertices
// Ordering [0-3] -fRtor cross section
// [4-7] +fRtor cross section such that [0] is below [4],
// [1] below [5] etc.
// Note:
// Caller has deletion resposibility
// Potential improvement: For last slice, use actual ending angle
// to avoid rounding error problems.
G4ThreeVectorList*
G4Torus::CreateRotatedVertices(const G4AffineTransform& pTransform,
G4int& noPolygonVertices) const
{
G4ThreeVectorList *vertices;
G4ThreeVector vertex0,vertex1,vertex2,vertex3;
G4double meshAngle,meshRMax,crossAngle,cosCrossAngle,sinCrossAngle,sAngle;
G4double rMaxX,rMaxY,rMinX,rMinY;
G4int crossSection,noCrossSections;
// Compute no of cross-sections necessary to mesh tube
noCrossSections=G4int (fDPhi/kMeshAngleDefault)+1;
if (noCrossSections<kMinMeshSections)
{
noCrossSections=kMinMeshSections;
}
else if (noCrossSections>kMaxMeshSections)
{
noCrossSections=kMaxMeshSections;
}
meshAngle=fDPhi/(noCrossSections-1);
meshRMax=(fRtor+fRmax)/cos(meshAngle*0.5);
// If complete in phi, set start angle such that mesh will be at fRmax
// on the x axis. Will give better extent calculations when not rotated.
if (fDPhi==M_PI*2.0&&fSPhi==0)
{
sAngle=-meshAngle*0.5;
}
else
{
sAngle=fSPhi;
}
vertices=new G4ThreeVectorList(noCrossSections*4);
if (vertices)
{
for (crossSection=0;crossSection<noCrossSections;crossSection++)
{
// Compute coordinates of cross section at section crossSection
crossAngle=sAngle+crossSection*meshAngle;
cosCrossAngle=cos(crossAngle);
sinCrossAngle=sin(crossAngle);
rMaxX=meshRMax*cosCrossAngle;
rMaxY=meshRMax*sinCrossAngle;
rMinX=(fRtor-fRmax)*cosCrossAngle;
rMinY=(fRtor-fRmax)*sinCrossAngle;
vertex0=G4ThreeVector(rMinX,rMinY,-fRmax);
vertex1=G4ThreeVector(rMaxX,rMaxY,-fRmax);
vertex2=G4ThreeVector(rMaxX,rMaxY,+fRmax);
vertex3=G4ThreeVector(rMinX,rMinY,+fRmax);
vertices->insert(pTransform.TransformPoint(vertex0));
vertices->insert(pTransform.TransformPoint(vertex1));
vertices->insert(pTransform.TransformPoint(vertex2));
vertices->insert(pTransform.TransformPoint(vertex3));
}
noPolygonVertices = 4 ;
}
else
{
G4Exception("G4Torus::CreateRotatedVertices Out of memory - Cannot alloc vertices");
}
return vertices;
}
///////////////////////////////////////////////////////////////////////
//
// No implementation for Visualisation Functions
void G4Torus::DescribeYourselfTo (G4VGraphicsScene& scene) const {
scene.AddThis (*this);
}
G4VisExtent G4Torus::GetExtent() const {
// Define the sides of the box into which the G4Torus instance would fit.
return G4VisExtent (-fRtor-fRmax, fRtor+fRmax,
-fRtor-fRmax, fRtor+fRmax, -fRmax, fRmax);
}
G4Polyhedron* G4Torus::CreatePolyhedron () const {
return new G4PolyhedronTorus (fRmin, fRmax, fRtor, fSPhi, fSPhi + fDPhi);
}
G4NURBS* G4Torus::CreateNURBS () const {
G4NURBS* pNURBS;
if (fRmin != 0) {
if (fDPhi >= 2.0 * M_PI) {
pNURBS = new G4NURBStube (fRmin, fRmax, fRtor);
}
else {
pNURBS = new G4NURBStubesector (fRmin, fRmax, fRtor, fSPhi, fSPhi + fDPhi);
}
}
else {
if (fDPhi >= 2.0 * M_PI) {
pNURBS = new G4NURBScylinder (fRmax, fRtor);
}
else {
const G4double epsilon = 1.e-4; // Cylinder sector not yet available!
pNURBS = new G4NURBStubesector (epsilon, fRmax, fRtor,
fSPhi, fSPhi + fDPhi);
}
}
return pNURBS;
}
//
//
/////////////////////////////////////////////////////////////////////////////