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author | toma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da> | 2009-11-25 17:56:58 +0000 |
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committer | toma <toma@283d02a7-25f6-0310-bc7c-ecb5cbfe19da> | 2009-11-25 17:56:58 +0000 |
commit | ce599e4f9f94b4eb00c1b5edb85bce5431ab3df2 (patch) | |
tree | d3bb9f5d25a2dc09ca81adecf39621d871534297 /kig/misc/cubic-common.cc | |
download | tdeedu-ce599e4f9f94b4eb00c1b5edb85bce5431ab3df2.tar.gz tdeedu-ce599e4f9f94b4eb00c1b5edb85bce5431ab3df2.zip |
Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.
BUG:215923
git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdeedu@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da
Diffstat (limited to 'kig/misc/cubic-common.cc')
-rw-r--r-- | kig/misc/cubic-common.cc | 527 |
1 files changed, 527 insertions, 0 deletions
diff --git a/kig/misc/cubic-common.cc b/kig/misc/cubic-common.cc new file mode 100644 index 00000000..029f1194 --- /dev/null +++ b/kig/misc/cubic-common.cc @@ -0,0 +1,527 @@ +// Copyright (C) 2003 Dominique Devriese <[email protected]> + +// This program is free software; you can redistribute it and/or +// modify it under the terms of the GNU General Public License +// as published by the Free Software Foundation; either version 2 +// of the License, or (at your option) any later version. + +// This program 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 General Public License for more details. + +// You should have received a copy of the GNU General Public License +// along with this program; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +// 02110-1301, USA. + +#include <config.h> + +#include "cubic-common.h" +#include "kignumerics.h" +#include "kigtransform.h" + +#ifdef HAVE_IEEEFP_H +#include <ieeefp.h> +#endif + +/* + * coefficients of the cartesian equation for cubics + */ + +CubicCartesianData::CubicCartesianData() +{ + std::fill( coeffs, coeffs + 10, 0 ); +} + +CubicCartesianData::CubicCartesianData( + const double incoeffs[10] ) +{ + std::copy( incoeffs, incoeffs + 10, coeffs ); +} + +const CubicCartesianData calcCubicThroughPoints ( + const std::vector<Coordinate>& points ) +{ + // points is a vector of at most 9 points through which the cubic is + // constrained. + // this routine should compute the coefficients in the cartesian equation + // they are defined up to a multiplicative factor. + // since we don't know (in advance) which one of them is nonzero, we + // simply keep all 10 parameters, obtaining a 9x10 linear system which + // we solve using gaussian elimination with complete pivoting + // If there are too few, then we choose some cool way to fill in the + // empty parts in the matrix according to the LinearConstraints + // given.. + + // 9 rows, 10 columns.. + double row0[10]; + double row1[10]; + double row2[10]; + double row3[10]; + double row4[10]; + double row5[10]; + double row6[10]; + double row7[10]; + double row8[10]; + double *matrix[9] = {row0, row1, row2, row3, row4, row5, row6, row7, row8}; + double solution[10]; + int scambio[10]; + + int numpoints = points.size(); + int numconstraints = 9; + + // fill in the matrix elements + for ( int i = 0; i < numpoints; ++i ) + { + double xi = points[i].x; + double yi = points[i].y; + matrix[i][0] = 1.0; + matrix[i][1] = xi; + matrix[i][2] = yi; + matrix[i][3] = xi*xi; + matrix[i][4] = xi*yi; + matrix[i][5] = yi*yi; + matrix[i][6] = xi*xi*xi; + matrix[i][7] = xi*xi*yi; + matrix[i][8] = xi*yi*yi; + matrix[i][9] = yi*yi*yi; + } + + for ( int i = 0; i < numconstraints; i++ ) + { + if (numpoints >= 9) break; // don't add constraints if we have enough + for (int j = 0; j < 10; ++j) matrix[numpoints][j] = 0.0; + bool addedconstraint = true; + switch (i) + { + case 0: + matrix[numpoints][7] = 1.0; + matrix[numpoints][8] = -1.0; + break; + case 1: + matrix[numpoints][7] = 1.0; + break; + case 2: + matrix[numpoints][9] = 1.0; + break; + case 3: + matrix[numpoints][4] = 1.0; + break; + case 4: + matrix[numpoints][5] = 1.0; + break; + case 5: + matrix[numpoints][3] = 1.0; + break; + case 6: + matrix[numpoints][1] = 1.0; + break; + + default: + addedconstraint = false; + break; + } + + if (addedconstraint) ++numpoints; + } + + if ( ! GaussianElimination( matrix, numpoints, 10, scambio ) ) + return CubicCartesianData::invalidData(); + // fine della fase di eliminazione + BackwardSubstitution( matrix, numpoints, 10, scambio, solution ); + + // now solution should contain the correct coefficients.. + return CubicCartesianData( solution ); +} + +const CubicCartesianData calcCubicCuspThroughPoints ( + const std::vector<Coordinate>& points ) +{ + // points is a vector of at most 4 points through which the cubic is + // constrained. Moreover the cubic is required to have a cusp at the + // origin. + + // 9 rows, 10 columns.. + double row0[10]; + double row1[10]; + double row2[10]; + double row3[10]; + double row4[10]; + double row5[10]; + double row6[10]; + double row7[10]; + double row8[10]; + double *matrix[9] = {row0, row1, row2, row3, row4, row5, row6, row7, row8}; + double solution[10]; + int scambio[10]; + + int numpoints = points.size(); + int numconstraints = 9; + + // fill in the matrix elements + for ( int i = 0; i < numpoints; ++i ) + { + double xi = points[i].x; + double yi = points[i].y; + matrix[i][0] = 1.0; + matrix[i][1] = xi; + matrix[i][2] = yi; + matrix[i][3] = xi*xi; + matrix[i][4] = xi*yi; + matrix[i][5] = yi*yi; + matrix[i][6] = xi*xi*xi; + matrix[i][7] = xi*xi*yi; + matrix[i][8] = xi*yi*yi; + matrix[i][9] = yi*yi*yi; + } + + for ( int i = 0; i < numconstraints; i++ ) + { + if (numpoints >= 9) break; // don't add constraints if we have enough + for (int j = 0; j < 10; ++j) matrix[numpoints][j] = 0.0; + bool addedconstraint = true; + switch (i) + { + case 0: + matrix[numpoints][0] = 1.0; // through the origin + break; + case 1: + matrix[numpoints][1] = 1.0; + break; + case 2: + matrix[numpoints][2] = 1.0; // no first degree term + break; + case 3: + matrix[numpoints][3] = 1.0; // a011 (x^2 coeff) = 0 + break; + case 4: + matrix[numpoints][4] = 1.0; // a012 (xy coeff) = 0 + break; + case 5: + matrix[numpoints][7] = 1.0; + matrix[numpoints][8] = -1.0; + break; + case 6: + matrix[numpoints][7] = 1.0; + break; + case 7: + matrix[numpoints][9] = 1.0; + break; + case 8: + matrix[numpoints][6] = 1.0; + break; + + default: + addedconstraint = false; + break; + } + + if (addedconstraint) ++numpoints; + } + + if ( ! GaussianElimination( matrix, numpoints, 10, scambio ) ) + return CubicCartesianData::invalidData(); + // fine della fase di eliminazione + BackwardSubstitution( matrix, numpoints, 10, scambio, solution ); + + // now solution should contain the correct coefficients.. + return CubicCartesianData( solution ); +} + +const CubicCartesianData calcCubicNodeThroughPoints ( + const std::vector<Coordinate>& points ) +{ + // points is a vector of at most 6 points through which the cubic is + // constrained. Moreover the cubic is required to have a node at the + // origin. + + // 9 rows, 10 columns.. + double row0[10]; + double row1[10]; + double row2[10]; + double row3[10]; + double row4[10]; + double row5[10]; + double row6[10]; + double row7[10]; + double row8[10]; + double *matrix[9] = {row0, row1, row2, row3, row4, row5, row6, row7, row8}; + double solution[10]; + int scambio[10]; + + int numpoints = points.size(); + int numconstraints = 9; + + // fill in the matrix elements + for ( int i = 0; i < numpoints; ++i ) + { + double xi = points[i].x; + double yi = points[i].y; + matrix[i][0] = 1.0; + matrix[i][1] = xi; + matrix[i][2] = yi; + matrix[i][3] = xi*xi; + matrix[i][4] = xi*yi; + matrix[i][5] = yi*yi; + matrix[i][6] = xi*xi*xi; + matrix[i][7] = xi*xi*yi; + matrix[i][8] = xi*yi*yi; + matrix[i][9] = yi*yi*yi; + } + + for ( int i = 0; i < numconstraints; i++ ) + { + if (numpoints >= 9) break; // don't add constraints if we have enough + for (int j = 0; j < 10; ++j) matrix[numpoints][j] = 0.0; + bool addedconstraint = true; + switch (i) + { + case 0: + matrix[numpoints][0] = 1.0; + break; + case 1: + matrix[numpoints][1] = 1.0; + break; + case 2: + matrix[numpoints][2] = 1.0; + break; + case 3: + matrix[numpoints][7] = 1.0; + matrix[numpoints][8] = -1.0; + break; + case 4: + matrix[numpoints][7] = 1.0; + break; + case 5: + matrix[numpoints][9] = 1.0; + break; + case 6: + matrix[numpoints][4] = 1.0; + break; + case 7: + matrix[numpoints][5] = 1.0; + break; + case 8: + matrix[numpoints][3] = 1.0; + break; + + default: + addedconstraint = false; + break; + } + + if (addedconstraint) ++numpoints; + } + + if ( ! GaussianElimination( matrix, numpoints, 10, scambio ) ) + return CubicCartesianData::invalidData(); + // fine della fase di eliminazione + BackwardSubstitution( matrix, numpoints, 10, scambio, solution ); + + // now solution should contain the correct coefficients.. + return CubicCartesianData( solution ); +} + +/* + * computation of the y value corresponding to some x value + */ + +double calcCubicYvalue ( double x, double ymin, double ymax, int root, + CubicCartesianData data, bool& valid, + int &numroots ) +{ + valid = true; + + // compute the third degree polinomial: + double a000 = data.coeffs[0]; + double a001 = data.coeffs[1]; + double a002 = data.coeffs[2]; + double a011 = data.coeffs[3]; + double a012 = data.coeffs[4]; + double a022 = data.coeffs[5]; + double a111 = data.coeffs[6]; + double a112 = data.coeffs[7]; + double a122 = data.coeffs[8]; + double a222 = data.coeffs[9]; + + // first the y^3 coefficient, it coming only from a222: + double a = a222; + // next the y^2 coefficient (from a122 and a022): + double b = a122*x + a022; + // next the y coefficient (from a112, a012 and a002): + double c = a112*x*x + a012*x + a002; + // finally the constant coefficient (from a111, a011, a001 and a000): + double d = a111*x*x*x + a011*x*x + a001*x + a000; + + return calcCubicRoot ( ymin, ymax, a, b, c, d, root, valid, numroots ); +} + +const Coordinate calcCubicLineIntersect( const CubicCartesianData& cu, + const LineData& l, + int root, bool& valid ) +{ + assert( root == 1 || root == 2 || root == 3 ); + + double a, b, c, d; + calcCubicLineRestriction ( cu, l.a, l.b-l.a, a, b, c, d ); + int numroots; + double param = + calcCubicRoot ( -1e10, 1e10, a, b, c, d, root, valid, numroots ); + return l.a + param*(l.b - l.a); +} + +/* + * calculate the cubic polynomial resulting from the restriction + * of a cubic to a line (defined by two "Coordinates": a point and a + * direction) + */ + +void calcCubicLineRestriction ( CubicCartesianData data, + Coordinate p, Coordinate v, + double& a, double& b, double& c, double& d ) +{ + a = b = c = d = 0; + + double a000 = data.coeffs[0]; + double a001 = data.coeffs[1]; + double a002 = data.coeffs[2]; + double a011 = data.coeffs[3]; + double a012 = data.coeffs[4]; + double a022 = data.coeffs[5]; + double a111 = data.coeffs[6]; + double a112 = data.coeffs[7]; + double a122 = data.coeffs[8]; + double a222 = data.coeffs[9]; + + // zero degree term + d += a000; + + // first degree terms + d += a001*p.x + a002*p.y; + c += a001*v.x + a002*v.y; + + // second degree terms + d += a011*p.x*p.x + a012*p.x*p.y + a022*p.y*p.y; + c += 2*a011*p.x*v.x + a012*(p.x*v.y + v.x*p.y) + 2*a022*p.y*v.y; + b += a011*v.x*v.x + a012*v.x*v.y + a022*v.y*v.y; + + // third degree terms: a111 x^3 + a222 y^3 + d += a111*p.x*p.x*p.x + a222*p.y*p.y*p.y; + c += 3*(a111*p.x*p.x*v.x + a222*p.y*p.y*v.y); + b += 3*(a111*p.x*v.x*v.x + a222*p.y*v.y*v.y); + a += a111*v.x*v.x*v.x + a222*v.y*v.y*v.y; + + // third degree terms: a112 x^2 y + a122 x y^2 + d += a112*p.x*p.x*p.y + a122*p.x*p.y*p.y; + c += a112*(p.x*p.x*v.y + 2*p.x*v.x*p.y) + a122*(v.x*p.y*p.y + 2*p.x*p.y*v.y); + b += a112*(v.x*v.x*p.y + 2*v.x*p.x*v.y) + a122*(p.x*v.y*v.y + 2*v.x*v.y*p.y); + a += a112*v.x*v.x*v.y + a122*v.x*v.y*v.y; +} + + +const CubicCartesianData calcCubicTransformation ( + const CubicCartesianData& data, + const Transformation& t, bool& valid ) +{ + double a[3][3][3]; + double b[3][3][3]; + CubicCartesianData dataout; + + int icount = 0; + for (int i=0; i < 3; i++) + { + for (int j=i; j < 3; j++) + { + for (int k=j; k < 3; k++) + { + a[i][j][k] = data.coeffs[icount++]; + if ( i < k ) + { + if ( i == j ) // case aiik + { + a[i][i][k] /= 3.; + a[i][k][i] = a[k][i][i] = a[i][i][k]; + } + else if ( j == k ) // case aijj + { + a[i][j][j] /= 3.; + a[j][i][j] = a[j][j][i] = a[i][j][j]; + } + else // case aijk (i<j<k) + { + a[i][j][k] /= 6.; + a[i][k][j] = a[j][i][k] = a[j][k][i] = + a[k][i][j] = a[k][j][i] = a[i][j][k]; + } + } + } + } + } + + Transformation ti = t.inverse( valid ); + if ( ! valid ) return dataout; + + for (int i = 0; i < 3; i++) + { + for (int j = 0; j < 3; j++) + { + for (int k = 0; k < 3; k++) + { + b[i][j][k] = 0.; + for (int ii = 0; ii < 3; ii++) + { + for (int jj = 0; jj < 3; jj++) + { + for (int kk = 0; kk < 3; kk++) + { + b[i][j][k] += a[ii][jj][kk]*ti.data( ii, i )*ti.data( jj, j )*ti.data( kk, k ); + } + } + } + } + } + } + +// assert (fabs(b[0][1][2] - b[1][2][0]) < 1e-8); // test a couple of cases +// assert (fabs(b[0][1][1] - b[1][1][0]) < 1e-8); + + // apparently, the above assertions are wrong ( due to rounding + // errors, Maurizio and I hope :) ), so since the symmetry is not + // present, we just take the sum of the parts of the matrix elements + // that should be symmetric, instead of taking one of them, and + // multiplying it.. + + dataout.coeffs[0] = b[0][0][0]; + dataout.coeffs[1] = b[0][0][1] + b[0][1][0] + b[1][0][0]; + dataout.coeffs[2] = b[0][0][2] + b[0][2][0] + b[2][0][0]; + dataout.coeffs[3] = b[0][1][1] + b[1][0][1] + b[1][1][0]; + dataout.coeffs[4] = b[0][1][2] + b[0][2][1] + b[1][2][0] + b[1][0][2] + b[2][1][0] + b[2][0][1]; + dataout.coeffs[5] = b[0][2][2] + b[2][0][2] + b[2][2][0]; + dataout.coeffs[6] = b[1][1][1]; + dataout.coeffs[7] = b[1][1][2] + b[1][2][1] + b[2][1][1]; + dataout.coeffs[8] = b[1][2][2] + b[2][1][2] + b[2][2][1]; + dataout.coeffs[9] = b[2][2][2]; + + return dataout; +} + +bool operator==( const CubicCartesianData& lhs, const CubicCartesianData& rhs ) +{ + for ( int i = 0; i < 10; ++i ) + if ( lhs.coeffs[i] != rhs.coeffs[i] ) + return false; + return true; +} + +CubicCartesianData CubicCartesianData::invalidData() +{ + CubicCartesianData ret; + ret.coeffs[0] = double_inf; + return ret; +} + +bool CubicCartesianData::valid() const +{ + return finite( coeffs[0] ); +} |