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Merge pull request #5585 from afabri/Kernel_23-rational_rotation-GF 

Kernel_23: Remove local reference in rational_rotation.h
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Sebastien Loriot 2021-04-17 11:21:14 +02:00 committed by GitHub
parent 39367c2313 e661acaccb
commit 6d63fcc465
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GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 21 additions and 34 deletions
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55
Kernel_23/include/CGAL/rational_rotation.h
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@ -27,13 +27,12 @@ template < class NT >
void void
rational_rotation_approximation( const NT & dirx, // dir.x() rational_rotation_approximation( const NT & dirx, // dir.x()
const NT & diry, // dir.y() const NT & diry, // dir.y()
NT & sin_num, // return NT & sin, // numerator return
NT & cos_num, // return NT & cos, // numerator return
NT & denom, // return NT & den, // denominator return
const NT & eps_num, // quality_bound const NT & eps_num, // quality_bound
const NT & eps_den ) const NT & eps_den )
{ {
const NT& n = eps_num; const NT& n = eps_num;
const NT& d = eps_den; const NT& d = eps_den;
const NT NT0 = NT(0) ; const NT NT0 = NT(0) ;
@ -41,12 +40,9 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
CGAL_kernel_precondition( (dirx != NT0) || (diry != NT0)); CGAL_kernel_precondition( (dirx != NT0) || (diry != NT0));
CGAL_kernel_precondition( n > NT0 ); CGAL_kernel_precondition( n > NT0 );
CGAL_kernel_precondition( d > NT0 ); CGAL_kernel_precondition( d > NT0 );
NT & sin = sin_num; NT dx = CGAL::abs(dirx);
NT & cos = cos_num; NT dy = CGAL::abs(diry);
NT & den = denom; NT sq_hypotenuse = square(dx) + square(dy);
NT dx = CGAL_NTS abs(dirx);
NT dy = CGAL_NTS abs(diry);
NT sq_hypotenuse = dx*dx + dy*dy;
NT common_part; NT common_part;
NT diff_part; NT diff_part;
NT rhs; NT rhs;
@ -59,7 +55,7 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
} }
// approximate sin = dy / sqrt(sq_hypotenuse) // approximate sin = dy / sqrt(sq_hypotenuse)
// if ( dy / sqrt(sq_hypotenuse) < n/d ) // if ( dy / sqrt(sq_hypotenuse) < n/d )
if (dy * dy * d * d < sq_hypotenuse * n * n) if (square(dy) * square(d) < sq_hypotenuse * square(n))
{ {
cos = NT1; cos = NT1;
sin = NT0; sin = NT0;
@ -79,7 +75,7 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
p = p0 + p1; p = p0 + p1;
q = q0 + q1; q = q0 + q1;
sin = NT(2)*p*q; sin = NT(2)*p*q;
den = p*p + q*q; den = square(p) + square(q);
// sanity check for approximation // sanity check for approximation
// sin/den < dy/sqrt(hypotenuse) + n/d // sin/den < dy/sqrt(hypotenuse) + n/d
@ -89,9 +85,9 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
// === (sin^2 d^2 + n^2 den^2)sq_hypotenuse - 2... < dy^2 d^2 den^2 // === (sin^2 d^2 + n^2 den^2)sq_hypotenuse - 2... < dy^2 d^2 den^2
// && (sin^2 d^2 + n^2 den^2)sq_hypotenuse + 2... > dy^2 d^2 den^2 // && (sin^2 d^2 + n^2 den^2)sq_hypotenuse + 2... > dy^2 d^2 den^2
common_part = (sin*sin*d*d + n*n*den*den)*sq_hypotenuse; common_part = (square(sin) * square(d) + square(n) * square(den))*sq_hypotenuse;
diff_part = NT(2)*n*sin*d*den*sq_hypotenuse; diff_part = NT(2)*n*sin*d*den*sq_hypotenuse;
rhs = dy*dy*d*d*den*den; rhs = square(dy) * square(d) * square(den);
upper_ok = (common_part - diff_part < rhs); upper_ok = (common_part - diff_part < rhs);
lower_ok = (common_part + diff_part > rhs); lower_ok = (common_part + diff_part > rhs);
@ -106,7 +102,7 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
// } // }
// else // else
// { // {
cos = q*q - p*p; cos = square(q) - square(p);
// } // }
break; break;
@ -114,7 +110,7 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
else else
{ {
// if ( dy/sqrt(sq_hypotenuse) < sin/den ) // if ( dy/sqrt(sq_hypotenuse) < sin/den )
if ( dy*dy*den*den < sin*sin*sq_hypotenuse ) if ( square(dy) * square(den) < square(sin) * sq_hypotenuse )
{ {
p1 = p; p1 = p;
q1 = q; q1 = q;
@ -130,24 +126,20 @@ rational_rotation_approximation( const NT & dirx, // dir.x()
dx = dirx; dx = dirx;
dy = diry; dy = diry;
if (CGAL_NTS abs(dy) > CGAL_NTS abs(dx) ) { std::swap (sin,cos); } if (CGAL::abs(dy) > CGAL::abs(dx) ) { std::swap (sin,cos); }
if (dx < NT0) { cos = - cos; } if (dx < NT0) { cos = - cos; }
if (dy < NT0) { sin = - sin; } if (dy < NT0) { sin = - sin; }
sin_num = sin;
cos_num = cos;
denom = den;
} }
template < class NT > template < class NT >
void void
rational_rotation_approximation( const double& angle, rational_rotation_approximation( const double& angle,
NT & sin_num, // return NT & isin, // numerator return
NT & cos_num, // return NT & icos, // numerator return
NT & denom, // return NT & iden, // denominator return
const NT & eps_num, // quality_bound const NT & eps_num, // quality_bound
const NT & eps_den ) const NT & eps_den )
{ {
@ -158,16 +150,14 @@ rational_rotation_approximation( const double& angle,
const NT NT1 = NT(1) ; const NT NT1 = NT(1) ;
CGAL_kernel_precondition( n > NT0 ); CGAL_kernel_precondition( n > NT0 );
CGAL_kernel_precondition( d > NT0 ); CGAL_kernel_precondition( d > NT0 );
NT& isin = sin_num;
NT& icos = cos_num;
NT& iden = denom;
double dsin = std::sin(angle); double dsin = std::sin(angle);
double dcos = std::cos(angle); double dcos = std::cos(angle);
double dn = CGAL::to_double(n); double dn = CGAL::to_double(n);
double dd = CGAL::to_double(d); double dd = CGAL::to_double(d);
double eps = dn / dd; double eps = dn / dd;
dsin = CGAL_NTS abs( dsin); dsin = CGAL::abs( dsin);
dcos = CGAL_NTS abs( dcos); dcos = CGAL::abs( dcos);
NT common_part; NT common_part;
NT diff_part; NT diff_part;
NT os; NT os;
@ -200,7 +190,7 @@ rational_rotation_approximation( const double& angle,
p = p0 + p1; p = p0 + p1;
q = q0 + q1; q = q0 + q1;
isin = NT(2)*p*q; isin = NT(2)*p*q;
iden = p*p + q*q; iden = square(p) + square(q);
// XXX sanity check for approximation // XXX sanity check for approximation
// sin/den < dsin + n/d // sin/den < dsin + n/d
@ -224,7 +214,7 @@ rational_rotation_approximation( const double& angle,
// } // }
// else // else
// { // {
icos = q*q - p*p; icos = square(q) - square(p);
// } // }
break; break;
@ -253,9 +243,6 @@ rational_rotation_approximation( const double& angle,
if (dcos < 0.0) { icos = - icos; } if (dcos < 0.0) { icos = - icos; }
if (dsin < 0.0) { isin = - isin; } if (dsin < 0.0) { isin = - isin; }
sin_num = isin;
cos_num = icos;
denom = iden;
} }
} //namespace CGAL } //namespace CGAL