GLdouble righ )

PARAMETERS
       left, righ Specify the coordinates for the left and right vertical clip‐
                  ping planes.

       _param3, _param4
                  Specify the coordinates for the  bottom  and  top  horizontal
                  clipping planes.

       _param5, _param6
                  Specify  the  distances to the nearer and farther depth clip‐
                  ping planes.  These values are negative if the plane is to be
                  behind the viewer.

DESCRIPTION
       glOrtho  describes a transformation that produces a parallel projection.
       The current matrix (see glMatrixMode) is multiplied by this  matrix  and
       the  result  replaces the current matrix, as if glMultMatrix were called
       with the following matrix as its argument:

               _________           0                     0           tx
              ⎝   0      _____________________           0           ty⎠
                  0               0            _____________________ tz
                  0               0                     0            1
       where
                                    tx=−_________

                              ty=−_____________________

                              tz=−_____________________

       Typically,  the  matrix  mode  is  GL_PROJECTION,  and  (left,  _param3,
       -_param5)  and (righ, _param4,  -_param5) specify the points on the near
       clipping plane that are mapped to the lower left and upper right corners
       of  the window, respectively, assuming that the eye is located at (0, 0,
       0).  -_param6 specifies the location of the far  clipping  plane.   Both
       _param5 and _param6 can be either positive or negative.

       Use  glPushMatrix and glPopMatrix to save and restore the current matrix
       stack.

ERRORS
       GL_INVALID_OPERATION is generated if glOrtho is executed between the ex‐
       ecution of glBegin and the corresponding execution of glEnd.

ASSOCIATED GETS
       glGet with argument GL_MATRIX_MODE
       glGet with argument GL_COLOR_MATRIX
       glGet with argument GL_MODELVIEW_MATRIX
       glGet with argument GL_PROJECTION_MATRIX
       glGet with argument GL_TEXTURE_MATRIX