OpenSceneGraph/src/osg/Matrix.cpp

#include <osg/Matrix>
#include <osg/Quat>
#include <osg/Notify>
#include <osg/Types>
#include <osg/Math>

#include <stdlib.h>

using namespace osg;

#define SET_ROW(row, v1, v2, v3, v4 )    \
    _mat[(row)][0] = (v1); \
    _mat[(row)][1] = (v2); \
    _mat[(row)][2] = (v3); \
    _mat[(row)][3] = (v4);

#define INNER_PRODUCT(a,b,r,c) \
     ((a)._mat[r][0] * (b)._mat[0][c]) \
    +((a)._mat[r][1] * (b)._mat[1][c]) \
    +((a)._mat[r][2] * (b)._mat[2][c]) \
    +((a)._mat[r][3] * (b)._mat[3][c])





Matrix::Matrix() : Object()
{
    makeIdentity();
}

Matrix::Matrix( const Matrix& other) : Object()
{
    set( (const float *) other._mat );
}

Matrix::Matrix( const float * const def )
{    
    set( def ); 
}

Matrix::Matrix( float a00, float a01, float a02, float a03,
                float a10, float a11, float a12, float a13,
                float a20, float a21, float a22, float a23,
                float a30, float a31, float a32, float a33)
{
    SET_ROW(0, a00, a01, a02, a03 )
    SET_ROW(1, a10, a11, a12, a13 )
    SET_ROW(2, a20, a21, a22, a23 )
    SET_ROW(3, a30, a31, a32, a33 )
}

void Matrix::set( float a00, float a01, float a02, float a03,
                  float a10, float a11, float a12, float a13,
                  float a20, float a21, float a22, float a23,
                  float a30, float a31, float a32, float a33)
{
    SET_ROW(0, a00, a01, a02, a03 )
    SET_ROW(1, a10, a11, a12, a13 )
    SET_ROW(2, a20, a21, a22, a23 )
    SET_ROW(3, a30, a31, a32, a33 )
}

void Matrix::setTrans( float tx, float ty, float tz )
{
    _mat[3][0] = tx;
    _mat[3][1] = ty;
    _mat[3][2] = tz;
}


void Matrix::setTrans( const Vec3& v )
{
    _mat[3][0] = v[0];
    _mat[3][1] = v[1];
    _mat[3][2] = v[2];
}

void Matrix::makeIdentity()
{
    SET_ROW(0,    1, 0, 0, 0 )
    SET_ROW(1,    0, 1, 0, 0 )
    SET_ROW(2,    0, 0, 1, 0 )
    SET_ROW(3,    0, 0, 0, 1 )
}

void Matrix::makeScale( const Vec3& v )
{
    makeScale(v[0], v[1], v[2] );
}

void Matrix::makeScale( float x, float y, float z )
{
    SET_ROW(0,    x, 0, 0, 0 )
    SET_ROW(1,    0, y, 0, 0 )
    SET_ROW(2,    0, 0, z, 0 )
    SET_ROW(3,    0, 0, 0, 1 )
}

void Matrix::makeTranslate( const Vec3& v )
{
    makeTranslate( v[0], v[1], v[2] );
}

void Matrix::makeTranslate( float x, float y, float z )
{
    SET_ROW(0,    1, 0, 0, 0 )
    SET_ROW(1,    0, 1, 0, 0 )
    SET_ROW(2,    0, 0, 1, 0 )
    SET_ROW(3,    x, y, z, 1 )
}

void Matrix::makeRotate( const Vec3& from, const Vec3& to )
{
    Quat quat;
    quat.makeRotate(from,to);
    quat.get(*this);
}

void Matrix::makeRotate( float angle, const Vec3& axis )
{
    Quat quat;
    quat.makeRotate( angle, axis);
    quat.get(*this);
}

void Matrix::makeRotate( float angle, float x, float y, float z ) 
{
    Quat quat;
    quat.makeRotate( angle, x, y, z);
    quat.get(*this);
}

void Matrix::makeRotate( const Quat& q )
{
    q.get(*this);    
}

void Matrix::makeRotate( float angle1, const Vec3& axis1, 
                         float angle2, const Vec3& axis2,
                         float angle3, const Vec3& axis3)
{
    Quat quat;
    quat.makeRotate(angle1, axis1, 
                    angle2, axis2,
                    angle3, axis3);
    quat.get(*this);
}

void Matrix::mult( const Matrix& lhs, const Matrix& rhs )
{   
    if (&lhs==this)
    {
        postMult(rhs);
        return;
    }
    if (&rhs==this)
    {
        preMult(lhs);
        return;
    }

// PRECONDITION: We assume neither &lhs nor &rhs == this
// if it did, use preMult or postMult instead
    _mat[0][0] = INNER_PRODUCT(lhs, rhs, 0, 0);
    _mat[0][1] = INNER_PRODUCT(lhs, rhs, 0, 1);
    _mat[0][2] = INNER_PRODUCT(lhs, rhs, 0, 2);
    _mat[0][3] = INNER_PRODUCT(lhs, rhs, 0, 3);
    _mat[1][0] = INNER_PRODUCT(lhs, rhs, 1, 0);
    _mat[1][1] = INNER_PRODUCT(lhs, rhs, 1, 1);
    _mat[1][2] = INNER_PRODUCT(lhs, rhs, 1, 2);
    _mat[1][3] = INNER_PRODUCT(lhs, rhs, 1, 3);
    _mat[2][0] = INNER_PRODUCT(lhs, rhs, 2, 0);
    _mat[2][1] = INNER_PRODUCT(lhs, rhs, 2, 1);
    _mat[2][2] = INNER_PRODUCT(lhs, rhs, 2, 2);
    _mat[2][3] = INNER_PRODUCT(lhs, rhs, 2, 3);
    _mat[3][0] = INNER_PRODUCT(lhs, rhs, 3, 0);
    _mat[3][1] = INNER_PRODUCT(lhs, rhs, 3, 1);
    _mat[3][2] = INNER_PRODUCT(lhs, rhs, 3, 2);
    _mat[3][3] = INNER_PRODUCT(lhs, rhs, 3, 3);
}

void Matrix::preMult( const Matrix& other )
{
    // brute force method requiring a copy
    //Matrix tmp(other* *this);
    // *this = tmp;

    // more efficient method just use a float[4] for temporary storage.
    float t[4];
    for(int col=0; col<4; ++col) {
        t[0] = INNER_PRODUCT( other, *this, 0, col );
        t[1] = INNER_PRODUCT( other, *this, 1, col );
        t[2] = INNER_PRODUCT( other, *this, 2, col );
        t[3] = INNER_PRODUCT( other, *this, 3, col );
        _mat[0][col] = t[0];
        _mat[1][col] = t[1];
        _mat[2][col] = t[2];
        _mat[3][col] = t[3];
    }

}

void Matrix::postMult( const Matrix& other )
{
    // brute force method requiring a copy
    //Matrix tmp(*this * other);
    // *this = tmp;

    // more efficient method just use a float[4] for temporary storage.
    float t[4];
    for(int row=0; row<4; ++row)
    {
        t[0] = INNER_PRODUCT( *this, other, row, 0 );
        t[1] = INNER_PRODUCT( *this, other, row, 1 );
        t[2] = INNER_PRODUCT( *this, other, row, 2 );
        t[3] = INNER_PRODUCT( *this, other, row, 3 );
        SET_ROW(row, t[0], t[1], t[2], t[3] )
    }
}

#undef INNER_PRODUCT


template <class T>
inline T SGL_ABS(T a)
{
   return (a >= 0 ? a : -a);
}

#ifndef SGL_SWAP
#define SGL_SWAP(a,b,temp) ((temp)=(a),(a)=(b),(b)=(temp))
#endif

bool Matrix::invert( const Matrix& mat )
{
    if (&mat==this) {
       Matrix tm(mat);
       return invert(tm);
    }

    unsigned int indxc[4], indxr[4], ipiv[4];
    unsigned int i,j,k,l,ll;
    unsigned int icol = 0;
    unsigned int irow = 0;
    float temp, pivinv, dum, big;

    // copy in place this may be unnecessary
    *this = mat;

    for (j=0; j<4; j++) ipiv[j]=0;

    for(i=0;i<4;i++)
    {
       big=(float)0.0;
       for (j=0; j<4; j++)
          if (ipiv[j] != 1)
             for (k=0; k<4; k++)
             {
                if (ipiv[k] == 0)
                {
                   if (SGL_ABS(operator()(j,k)) >= big)
                   {
                      big = SGL_ABS(operator()(j,k));
                      irow=j;
                      icol=k;
                   }
                }
                else if (ipiv[k] > 1)
                   return false;
             }
       ++(ipiv[icol]);
       if (irow != icol)
          for (l=0; l<4; l++) SGL_SWAP(operator()(irow,l),
                                       operator()(icol,l),
                                       temp);

       indxr[i]=irow;
       indxc[i]=icol;
       if (operator()(icol,icol) == 0)
          return false;

       pivinv = 1.0/operator()(icol,icol);
       operator()(icol,icol) = 1;
       for (l=0; l<4; l++) operator()(icol,l) *= pivinv;
       for (ll=0; ll<4; ll++)
          if (ll != icol)
          {
             dum=operator()(ll,icol);
             operator()(ll,icol) = 0;
             for (l=0; l<4; l++) operator()(ll,l) -= operator()(icol,l)*dum;
          }
    }
    for (int lx=4; lx>0; --lx)
    {
       if (indxr[lx-1] != indxc[lx-1])
          for (k=0; k<4; k++) SGL_SWAP(operator()(k,indxr[lx-1]),
                                       operator()(k,indxc[lx-1]),temp);
    }

    return true;
}

void Matrix::makeOrtho(double left, double right,
                       double bottom, double top,
                       double zNear, double zFar)
{
    // note transpose of Matrix wr.t OpenGL documentation, since the OSG use post multiplication rather than pre.
    double tx = -(right+left)/(right-left);
    double ty = -(top+bottom)/(top-bottom);
    double tz = -(zFar+zNear)/(zFar-zNear);
    SET_ROW(0, 2.0f/(right-left),              0.0f,               0.0f, 0.0f )
    SET_ROW(1,              0.0f, 2.0f/(top-bottom),               0.0f, 0.0f )
    SET_ROW(2,              0.0f,              0.0f, -2.0f/(zFar-zNear), 0.0f )
    SET_ROW(3,                tx,                ty,                 tz, 1.0f )
}

void Matrix::makeFrustum(double left, double right,
                         double bottom, double top,
                         double zNear, double zFar)
{
    // note transpose of Matrix wr.t OpenGL documentation, since the OSG use post multiplication rather than pre.
    double A = (right+left)/(right-left);
    double B = (top+bottom)/(top-bottom);
    double C = -(zFar+zNear)/(zFar-zNear);
    double D = -2.0*zFar*zNear/(zFar-zNear);
    SET_ROW(0, 2.0f*zNear/(right-left),                    0.0f, 0.0f,  0.0f )
    SET_ROW(1,                    0.0f, 2.0f*zNear/(top-bottom), 0.0f,  0.0f )
    SET_ROW(2,                       A,                       B,    C, -1.0f )
    SET_ROW(3,                    0.0f,                   0.0f,     D,  0.0f )
}


void Matrix::makePerspective(double fovy,double aspectRatio,
                             double zNear, double zFar)
{
    // calculate the appropriate left, right etc.
    double tan_fovy = tan(DegreesToRadians(fovy*0.5));
    double right  =  tan_fovy * aspectRatio * zNear;
    double left   = -right;
    double top    =  tan_fovy * zNear;
    double bottom =  -top;
    makeFrustum(left,right,bottom,top,zNear,zFar);
}


void Matrix::makeLookAt(const Vec3& eye,const Vec3& center,const Vec3& up)
{
    Vec3 f(center-eye);
    f.normalize();
    Vec3 s(f^up);
    s.normalize();
    Vec3 u(s^f);
    u.normalize();

    set(
        s[0],     u[0],     -f[0],     0.0f,
        s[1],     u[1],     -f[1],     0.0f,
        s[2],     u[2],     -f[2],     0.0f,
        0.0f,     0.0f,     0.0f,      1.0f);

    preMult(Matrix::translate(-eye));
}

#undef SET_ROW