// Filename: matrixLens.I
// Created by:  drose (12Dec01)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) Carnegie Mellon University.  All rights reserved.
//
// All use of this software is subject to the terms of the revised BSD
// license.  You should have received a copy of this license along
// with this source code in a file named "LICENSE."
//
////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::Constructor
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
INLINE MatrixLens::
MatrixLens() :
  _user_mat(LMatrix4f::ident_mat()),
  _ml_flags(0)
{
  // The default film size for a MatrixLens is 2, which makes the
  // default range for both X and Y be [-1, 1].  This also,
  // incidentally, makes the film_mat be identity.
  set_film_size(2.0f);
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::Copy Constructor
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
INLINE MatrixLens::
MatrixLens(const MatrixLens &copy) : 
  Lens(copy),
  _user_mat(copy._user_mat),
  _left_eye_mat(copy._left_eye_mat),
  _right_eye_mat(copy._right_eye_mat),
  _ml_flags(copy._ml_flags)
{
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::Copy Assignment Operator
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
INLINE void MatrixLens::
operator = (const MatrixLens &copy) {
  Lens::operator = (copy);
  _user_mat = copy._user_mat;
  _left_eye_mat = copy._left_eye_mat;
  _right_eye_mat = copy._right_eye_mat;
  _ml_flags = copy._ml_flags;
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::set_user_mat
//       Access: Published
//  Description: Explicitly specifies the projection matrix.  This
//               matrix should convert X and Y to the range
//               [-film_size/2, film_size/2], where (-fs/2,-fs/2) is
//               the lower left corner of the screen and (fs/2, fs/2)
//               is the upper right.  Z should go to the range [-1,
//               1], where -1 is the far plane and 1 is the near
//               plane.  Note that this is a left-handed Y-up
//               coordinate system.
//
//               The default film_size for a MatrixLens is 2, so the
//               default range is [-1, 1] for both X and Y.  This is
//               consistent with the GL conventions for projection
//               matrices.
////////////////////////////////////////////////////////////////////
INLINE void MatrixLens::
set_user_mat(const LMatrix4f &user_mat) {
  _user_mat = user_mat;
  adjust_comp_flags(CF_mat, 0);
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::get_user_mat
//       Access: Published
//  Description: Returns the explicit projection matrix as set by the
//               user.  This does not include transforms on the lens
//               or film (e.g. a film offset or view hpr).
////////////////////////////////////////////////////////////////////
INLINE const LMatrix4f &MatrixLens::
get_user_mat() const {
  return _user_mat;
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::set_left_eye_mat
//       Access: Published
//  Description: Sets a custom projection matrix for the left eye.
//               This is only used if the lens is attached to a stereo
//               camera, in which case the left eye matrix will be
//               used to draw the scene in the left eye (but the
//               center matrix--the user_mat--will still be used to
//               cull the scene).
//
//               This matrix should not be too different from the
//               center matrix (set by set_user_mat()) or culling
//               errors may become obvious.
////////////////////////////////////////////////////////////////////
INLINE void MatrixLens::
set_left_eye_mat(const LMatrix4f &left_eye_mat) {
  _left_eye_mat = left_eye_mat;
  _ml_flags |= MF_has_left_eye;
  adjust_comp_flags(CF_mat, 0);
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::clear_left_eye_mat
//       Access: Published
//  Description: Removes the custom projection matrix set for the left
//               eye, and uses the center matrix (set by set_user_mat)
//               instead.
////////////////////////////////////////////////////////////////////
INLINE void MatrixLens::
clear_left_eye_mat() {
  _ml_flags &= ~MF_has_left_eye;
  adjust_comp_flags(CF_mat, 0);
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::has_left_eye_mat
//       Access: Published
//  Description: Returns true if the camera has a custom projection
//               matrix set for the left eye, or false if the center
//               matrix (set by set_user_mat) will be used for the
//               left eye.
////////////////////////////////////////////////////////////////////
INLINE bool MatrixLens::
has_left_eye_mat() const {
  return (_ml_flags & MF_has_left_eye) != 0;
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::get_left_eye_mat
//       Access: Published
//  Description: Returns the custom projection matrix for the left
//               eye, if any, or the center matrix if there is no
//               custom matrix set for the left eye.
////////////////////////////////////////////////////////////////////
INLINE const LMatrix4f &MatrixLens::
get_left_eye_mat() const {
  if ((_ml_flags & MF_has_left_eye) != 0) {
    return _left_eye_mat;
  }
  return _user_mat;
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::set_right_eye_mat
//       Access: Published
//  Description: Sets a custom projection matrix for the right eye.
//               This is only used if the lens is attached to a stereo
//               camera, in which case the right eye matrix will be
//               used to draw the scene in the right eye (but the
//               center matrix--the user_mat--will still be used to
//               cull the scene).
//
//               This matrix should not be too different from the
//               center matrix (set by set_user_mat()) or culling
//               errors may become obvious.
////////////////////////////////////////////////////////////////////
INLINE void MatrixLens::
set_right_eye_mat(const LMatrix4f &right_eye_mat) {
  _right_eye_mat = right_eye_mat;
  _ml_flags |= MF_has_right_eye;
  adjust_comp_flags(CF_mat, 0);
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::clear_right_eye_mat
//       Access: Published
//  Description: Removes the custom projection matrix set for the right
//               eye, and uses the center matrix (set by set_user_mat)
//               instead.
////////////////////////////////////////////////////////////////////
INLINE void MatrixLens::
clear_right_eye_mat() {
  _ml_flags &= ~MF_has_right_eye;
  adjust_comp_flags(CF_mat, 0);
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::has_right_eye_mat
//       Access: Published
//  Description: Returns true if the camera has a custom projection
//               matrix set for the right eye, or false if the center
//               matrix (set by set_user_mat) will be used for the
//               right eye.
////////////////////////////////////////////////////////////////////
INLINE bool MatrixLens::
has_right_eye_mat() const {
  return (_ml_flags & MF_has_right_eye) != 0;
}

////////////////////////////////////////////////////////////////////
//     Function: MatrixLens::get_right_eye_mat
//       Access: Published
//  Description: Returns the custom projection matrix for the right
//               eye, if any, or the center matrix if there is no
//               custom matrix set for the right eye.
////////////////////////////////////////////////////////////////////
INLINE const LMatrix4f &MatrixLens::
get_right_eye_mat() const {
  if ((_ml_flags & MF_has_right_eye) != 0) {
    return _right_eye_mat;
  }
  return _user_mat;
}