C++ Matrix3::getColumn方法代码示例

/** get the world tansform of the linked position
 * @param worldTrans out parameter to palce transform in
 * @warning this method is called by physics library and should
 * not be called directly
 */
void MotionState::getWorldTransform(btTransform &worldTrans) const
{
	// set the location/origin
	Vector3 l = this->shape._getTranslation();
    if (this->position != nullptr)
        l += this->position->getLocation();
	worldTrans.setOrigin (btVector3(l.x(), l.y(), l.z()));
	
	// set the basis/rotational matrix
	// since openGL matrix is column major and Bullet is row
	// major, we have to do some converting

    Matrix3 matrix;
    if (this->position != nullptr)
    {
        matrix.setColumn(0, this->position->getLocalXAxis());
        matrix.setColumn(1, this->position->getUpVector());
        matrix.setColumn(2, this->position->getForwardVector());
    }
    matrix.multiply(this->shape._getRotation());


    btMatrix3x3 rot;
    rot.setValue(

        // fill in x axis, first column
        matrix.getColumn(0).x(),
        matrix.getColumn(0).y(),
        matrix.getColumn(0).z(),

        // fill in y axis, second column
        matrix.getColumn(1).x(),
        matrix.getColumn(1).y(),
        matrix.getColumn(1).z(),
                                
        // fill in z axis, thrid column
        matrix.getColumn(2).x(),
        matrix.getColumn(2).y(),
        matrix.getColumn(2).z()
    
    );
	worldTrans.setBasis(rot);
}

Real
estimateScalingFactor(Matrix3 const & m)
{
  return (m.getColumn(0).fastLength() + m.getColumn(1).fastLength() + m.getColumn(2).fastLength()) / 3.0f;
}

Matrix3
orthonormalBasisMatrix(Matrix3 const & m)
{
  return orthonormalBasisMatrix(m.getColumn(0), m.getColumn(1), m.getColumn(2));
}

inline Vector3 Camera::getWorldRVector() const
{
	Matrix3 m = world.getRotate();
    return m.getColumn(2);
}

bool WindowedApp3d::moveObject ()
{
    // The coordinate system in which the rotations are applied is that of
    // the object's parent, if it has one.  The parent's world rotation
    // matrix is R, of which the columns are the coordinate axis directions.
    // Column 0 is "direction", column 1 is "up", and column 2 is "right".
    // If the object does not have a parent, the world coordinate axes are
    // used, in which case the rotation matrix is I, the identity.  Column 0
    // is (1,0,0) and is "direction", column 1 is (0,1,0) and is "up", and
    // column 2 is (0,0,1) and is "right".  This choice is consistent with
    // the use of rotations in the Camera and Light classes to store
    // coordinate axes.
    //
    // Roll is about the "direction" axis, yaw is about the "up" axis, and
    // pitch is about the "right" axis.

    if ( !m_bCameraMoveable || !motionObject )
        return false;

    RenderObject* pkParent = motionObject->getParent();
    Vector3 kAxis;
    float fAngle;
    Matrix3 kRot, kIncr;

	Matrix3 m;
    if ( m_iDoRoll )
    {
		
		motionObject->localTrans.getMatrix(m);
        kRot = m;

        fAngle = m_iDoRoll*m_fRotSpeed;
        if ( pkParent )
		{
			pkParent->worldTrans.getMatrix(m);	
            kAxis = m.getColumn(0);
		}
        else
            kAxis = Vector3::UNIT_X;

        kIncr.fromAxisAngle(kAxis,fAngle);
        motionObject->localTrans.setMatrix(kIncr*kRot);
        return true;
    }
	
    if ( m_iDoYaw )
    {
		motionObject->localTrans.getMatrix(m);
        kRot = m;

        fAngle = m_iDoYaw*m_fRotSpeed;
        if ( pkParent )
		{
			pkParent->worldTrans.getMatrix(m);	
            kAxis = m.getColumn(1);
		}
        else
            kAxis = Vector3::UNIT_Y;

        kIncr.fromAxisAngle(kAxis,fAngle);
        motionObject->localTrans.setMatrix(kIncr*kRot);
        return true;
    }

    if ( m_iDoPitch )
    {
		motionObject->localTrans.getMatrix(m);
        kRot = m;

        fAngle = m_iDoPitch*m_fRotSpeed;
        if ( pkParent )
		{
            pkParent->worldTrans.getMatrix(m);	
            kAxis = m.getColumn(2);
		}
        else
            kAxis = Vector3::UNIT_Z;

        kIncr.fromAxisAngle(kAxis,fAngle);
        motionObject->localTrans.setMatrix(kIncr*kRot);
        return true;
    }

    return false;
}