vcglib/vcg/math/matrix.h

586 lines
14 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2004 \/)\/ *
* Visual Computing Lab /\/| *
* ISTI - Italian National Research Council | *
* \ *
* All rights reserved. *
* *
* 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 (http://www.gnu.org/licenses/gpl.txt) *
* for more details. *
* *
****************************************************************************/
#include <stdio.h>
#include <math.h>
#include <memory.h>
#include <assert.h>
#include <algorithm>
namespace vcg
{
/** \addtogroup math */
/* @{ */
/*!
* This class represent a generic <I>m</I>×<I>n</I> matrix. The class is templated over the scalar type field.
* @param TYPE (Templete Parameter) Specifies the ScalarType field.
*/
template<class TYPE>
class Matrix
{
public:
typedef TYPE ScalarType;
/*!
* Default constructor
* All the elements are initialized to zero.
* \param m the number of matrix rows
* \param n the number of matrix columns
*/
Matrix(unsigned int m, unsigned int n)
{
_rows = m;
_columns = n;
_data = new ScalarType[m*n];
memset(_data, 0, m*n*sizeof(ScalarType));
};
/*!
* Constructor
* The matrix elements are initialized with the values of the elements in \i values.
* \param m the number of matrix rows
* \param n the number of matrix columns
* \param values the values of the matrix elements
*/
Matrix(unsigned int m, unsigned int n, TYPE *values)
{
_rows = m;
_columns = n;
_data = new ScalarType[m*n];
unsigned int i;
for (i=0; i<_rows*_columns; i++)
_data[i] = values[i];
};
/*!
* Copy constructor
* The matrix elements are initialized with the value of the corresponding element in \i m
* \param m the matrix to be copied
*/
Matrix(const Matrix<TYPE> &m)
{
_rows = m._rows;
_columns = m._columns;
_data = new ScalarType[_rows*_columns];
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] = m._data[i];
};
/*!
* Default destructor
*/
~Matrix()
{
delete []_data;
};
/*!
* Number of columns
*/
inline unsigned int ColumnsNumber() const
{
return _columns;
};
/*!
* Number of rows
*/
inline unsigned int RowsNumber() const
{
return _rows;
};
/*!
* Equality operator.
* \param m
* \return true iff the matrices have same size and its elements have same values.
*/
bool operator==(const Matrix<TYPE> &m) const
{
if (_rows==m._rows && _columns==m._columns)
{
bool result = true;
for (unsigned int i=0; i<_rows*_columns && result; i++)
result = (_data[i]==m._data[i]);
return result;
}
return false;
};
/*!
* Inequality operator
* \param m
* \return true iff the matrices have different size or if their elements have different values.
*/
bool operator!=(const Matrix<TYPE> &m) const
{
if (_rows==m._rows && _columns==m._columns)
{
bool result = false;
for (unsigned int i=0; i<_rows*_columns && !result; i++)
result = (_data[i]!=m._data[i]);
return result;
}
return true;
};
/*!
* Return the element stored in the <I>i</I>-th rows at the <I>j</I>-th column
* \param i the row index
* \param j the column index
* \return the element
*/
inline TYPE ElementAt(unsigned int i, unsigned int j)
{
assert(i>=0 && i<_rows);
assert(j>=0 && j<_columns);
return _data[i*_columns+j];
};
/*!
* Calculate and return the matrix determinant (Laplace)
* \return the matrix determinant
*/
TYPE Determinant() const
{
assert(_rows == _columns);
switch (_rows)
{
case 2:
{
return _data[0]*_data[3]-_data[1]*_data[2];
break;
};
case 3:
{
return _data[0]*(_data[4]*_data[8]-_data[5]*_data[7]) -
_data[1]*(_data[3]*_data[8]-_data[5]*_data[6]) +
_data[2]*(_data[3]*_data[7]-_data[4]*_data[6]) ;
break;
};
default:
{
// da migliorare: si puo' cercare la riga/colonna con maggior numero di zeri
ScalarType det = 0;
for (unsigned int j=0; j<_columns; j++)
if (_data[j]!=0)
det += _data[j]*this->Cofactor(0, j);
return det;
}
};
};
/*!
* Return the cofactor <I>A<SUB>i,j</SUB></I> of the <I>a<SUB>i,j</SUB></I> element
* \return ...
*/
TYPE Cofactor(unsigned int i, unsigned int j) const
{
assert(_rows == _columns);
assert(_rows>2);
TYPE *values = new TYPE[(_rows-1)*(_columns-1)];
unsigned int u, v, p, q, s, t;
for (u=0, p=0, s=0, t=0; u<_rows; u++, t+=_rows)
{
if (i==u)
continue;
for (v=0, q=0; v<_columns; v++)
{
if (j==v)
continue;
values[s+q] = _data[t+v];
q++;
}
p++;
s+=(_rows-1);
}
Matrix<TYPE> temp(_rows-1, _columns-1, values);
return (pow(-1, i+j)*temp.Determinant());
};
/*!
* Subscript operator:
* \param i the index of the row
* \return a reference to the <I>i</I>-th matrix row
*/
inline TYPE* operator[](const unsigned int i)
{
assert(i>=0 && i<_rows);
return _data + i*_columns;
};
/*!
* Const subscript operator
* \param i the index of the row
* \return a reference to the <I>i</I>-th matrix row
*/
inline const TYPE* operator[](const unsigned int i) const
{
assert(i>=0 && i<_rows);
return _data + i*_columns;
};
/*!
* Get the <I>j</I>-th column on the matrix.
* \param j the column index.
* \return the reference to the column elements.
*/
TYPE* GetColumn(const unsigned int j)
{
assert(j>=0 && j<_columns);
ScalarType *v = new ScalarType[_columns];
unsigned int i, p;
for (i=0, p=j; i<_rows; i++, p+=_columns)
v[i] = _data[p];
return v;
};
/*!
* Get the <I>i</I>-th row on the matrix.
* \param i the column index.
* \return the reference to the row elements.
*/
TYPE* GetRow(const unsigned int i)
{
assert(i>=0 && i<_rows);
ScalarType *v = new ScalarType[_rows];
unsigned int j, p;
for (j=0, p=i*_columns; j<_columns; j++, p++)
v[j] = _data[p];
return v;
};
/*!
* Assignment operator
* \param m ...
*/
Matrix<TYPE>& operator=(const Matrix<TYPE> &m)
{
if (this != &m)
{
assert(_rows == m._rows);
assert(_columns == m._columns);
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] = m._data[i];
}
return *this;
};
/*!
* Adds a matrix <I>m</I> to this matrix.
* \param m reference to matrix to add to this
* \return the matrix sum.
*/
Matrix<TYPE>& operator+=(const Matrix<TYPE> &m)
{
assert(_rows == m._rows);
assert(_columns == m._columns);
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] += m._data[i];
return *this;
};
/*!
* Subtracts a matrix <I>m</I> to this matrix.
* \param m reference to matrix to subtract
* \return the matrix difference.
*/
Matrix<TYPE>& operator-=(const Matrix<TYPE> &m)
{
assert(_rows == m._rows);
assert(_columns == m._columns);
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] -= m._data[i];
return *this;
};
/*!
* (Modifier) Add to each element of this matrix the scalar constant <I>k</I>.
* \param k the scalar constant
* \return the modified matrix
*/
Matrix<TYPE>& operator+=(const TYPE k)
{
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] += k;
return *this;
};
/*!
* (Modifier) Subtract from each element of this matrix the scalar constant <I>k</I>.
* \param k the scalar constant
* \return the modified matrix
*/
Matrix<TYPE>& operator-=(const TYPE k)
{
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] -= k;
return *this;
};
/*!
* (Modifier) Multiplies each element of this matrix by the scalar constant <I>k</I>.
* \param k the scalar constant
* \return the modified matrix
*/
Matrix<TYPE>& operator*=(const TYPE k)
{
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] *= k;
return *this;
};
/*!
* (Modifier) Divides each element of this matrix by the scalar constant <I>k</I>.
* \param k the scalar constant
* \return the modified matrix
*/
Matrix<TYPE>& operator/=(const TYPE k)
{
assert(k!=0);
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] /= k;
return *this;
};
/*!
* Matrix multiplication: calculates the cross product.
* \param reference to the matrix to multiply by
* \return the matrix product
*/
Matrix<TYPE> operator*(const Matrix<TYPE> &m)
{
assert(_columns == m._rows);
Matrix<TYPE> result(_rows, m._columns);
unsigned int i, j, k, p, q, r;
for (i=0, p=0, r=0; i<result._rows; i++, p+=_columns, r+=result._columns)
for (j=0; j<result._columns; j++)
{
ScalarType temp = 0;
for (k=0, q=0; k<_columns; k++, q+=m._columns)
temp+=(_data[p+k]*m._data[q+j]);
result._data[r+j] = temp;
}
return result;
};
/*!
* Matrix-vector multiplication.
* \param reference to the 3-dimensional vector to multiply by
* \return the resulting vector
*/
vcg::Point3<TYPE> operator*(const vcg::Point3<TYPE> &p)
{
assert(_columns==3 && _rows==3);
vcg::Point3<TYPE> result;
result[0] = _data[0]*p[0]+_data[1]*p[1]+_data[2]*p[2];
result[1] = _data[3]*p[0]+_data[4]*p[1]+_data[5]*p[2];
result[2] = _data[6]*p[0]+_data[7]*p[1]+_data[8]*p[2];
return result;
};
/*!
* Scalar sum.
* \param k
* \return the resultant matrix
*/
Matrix<TYPE> operator+(const TYPE k)
{
Matrix<TYPE> result(_rows, _columns);
for (unsigned int i=0; i<_rows*_columns; i++)
result._data[i] = _data[i]+k;
return result;
};
/*!
* Scalar difference.
* \param k
* \return the resultant matrix
*/
Matrix<TYPE> operator-(const TYPE k)
{
Matrix<TYPE> result(_rows, _columns);
for (unsigned int i=0; i<_rows*_columns; i++)
result._data[i] = _data[i]-k;
return result;
};
/*!
* Negate all matrix elements
* \return the modified matrix
*/
Matrix<TYPE> operator-() const
{
Matrix<TYPE> result(_rows, _columns, _data);
for (unsigned int i=0; i<_columns*_rows; i++)
result._data[i] = -1*_data[i];
return result;
};
/*!
* Scalar multiplication.
* \param k value to multiply every member by
* \return the resultant matrix
*/
Matrix<TYPE> operator*(const TYPE k)
{
Matrix<TYPE> result(_rows, _columns);
for (unsigned int i=0; i<_rows*_columns; i++)
result._data[i] = _data[i]*k;
return result;
};
/*!
* Scalar division.
* \param k value to divide every member by
* \return the resultant matrix
*/
Matrix<TYPE> operator/(const TYPE k)
{
Matrix<TYPE> result(_rows, _columns);
for (unsigned int i=0; i<_rows*_columns; i++)
result._data[i] = _data[i]/k;
return result;
};
/*!
* Set all the matrix elements to zero.
*/
void SetZero()
{
for (unsigned int i=0; i<_rows*_columns; i++)
_data[i] = ScalarType(0.0);
};
/*!
* Set the values of <I>j</I>-th column to v[j]
* \param j the column index
* \param v ...
*/
void SetColumn(const unsigned int j, TYPE* v)
{
assert(j>=0 && j<_columns);
unsigned int i, p;
for (i=0, p=0; i<_rows; i++, p+=_columns)
_data[p] = v[i];
};
/*!
* Set the elements of the <I>i</I>-th row to v[j]
* \param i the row index
* \param v ...
*/
void SetRow(const unsigned int i, TYPE* v)
{
assert(i>=0 && i<_rows);
unsigned int j, p;
for (j=0, p=i*_rows; j<_columns; j++, p++)
_data[p] = v[j];
};
/*!
* Set the diagonal elements <I>v<SUB>i,i</SUB></I> to v[i]
* \param v
*/
void SetDiagonal(TYPE *v)
{
assert(_rows == _columns);
for (unsigned int i=0, p=0; i<_rows; i++, p+=_rows)
_data[p+i] = v[i];
};
/*!
* Resize the current matrix.
* \param m the number of matrix rows.
* \param n the number of matrix columns.
*/
void Resize(const unsigned int m, const unsigned int n)
{
assert(m>=2);
assert(n>=2);
_rows = m;
_columns = n;
delete []_data;
_data = new ScalarType[m*n];
for (unsigned int i=0; i<m*n; i++)
_data[i] = 0;
};
/*!
* Matrix transposition operation: set the current matrix to its transpose
*/
void Transpose()
{
ScalarType *temp = new ScalarType[_rows*_columns];
unsigned int i, j, p, q;
for (i=0, p=0; i<_rows; i++, p+=_columns)
for (j=0, q=0; j<_columns; j++, q+=_rows)
temp[q+i] = _data[p+j];
std::swap(_columns, _rows);
std::swap(_data, temp);
delete []temp;
};
/*!
* Print all matrix elements
*/
void Dump()
{
unsigned int i, j, p;
for (i=0, p=0; i<_rows; i++, p+=_columns)
{
printf("[\t");
for (j=0; j<_columns; j++)
printf("%g\t", _data[p+j]);
printf("]\n");
}
printf("\n");
};
protected:
/// the number of matrix rows
unsigned int _rows;
/// the number of matrix rows
unsigned int _columns;
/// the matrix elements
ScalarType *_data;
};
/*! @} */
}; // end of namespace