_c_l_i_p_W Specify the clip w coordinate to be mapped.
_m_o_d_e_l Specifies the modelview matrix (as from a ggggllllGGGGeeeettttDDDDoooouuuubbbblllleeeevvvv
call).
_p_r_o_j Specifies the projection matrix (as from a ggggllllGGGGeeeettttDDDDoooouuuubbbblllleeeevvvv
call).
_v_i_e_w Specifies the viewport (as from a ggggllllGGGGeeeettttIIIInnnntttteeeeggggeeeerrrrvvvv call).
_n_e_a_r, _f_a_r Specifies the near and far planes (as from a ggggllllGGGGeeeettttDDDDoooouuuubbbblllleeeevvvv
call).
_o_b_j_X, _o_b_j_Y, _o_b_j_Z, _o_b_j_W
Returns the computed object coordinates.
DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
gggglllluuuuUUUUnnnnPPPPrrrroooojjjjeeeecccctttt4444 maps the specified window coordinates _w_i_n_X, _w_i_n_Y and _w_i_n_Z
and its clip w coordinate _c_l_i_p_W into object coordinates (_o_b_j_X, _o_b_j_Y,
_o_b_j_Z, _o_b_j_W) using _m_o_d_e_l, _p_r_o_j and _v_i_e_w. _c_l_i_p_W can be other than 1 as for
vertices in ggggllllFFFFeeeeeeeeddddbbbbaaaacccckkkkBBBBuuuuffffffffeeeerrrr when data type GGGGLLLL____4444DDDD____CCCCOOOOLLLLOOOORRRR____TTTTEEEEXXXXTTTTUUUURRRREEEE is
returned. This also handles the case where the _n_e_a_r and _f_a_r planes are
different from the default, 0 and 1, respectively. A return value of
GGGGLLLL____TTTTRRRRUUUUEEEE indicates success; a return value of GGGGLLLL____FFFFAAAALLLLSSSSEEEE indicates failure.
To compute the coordinates (_o_b_j_X, _o_b_j_Y, _o_b_j_Z and _o_b_j_W), gggglllluuuuUUUUnnnnPPPPrrrroooojjjjeeeecccctttt4444
multiplies the normalized device coordinates by the inverse of _m_o_d_e_l*_p_r_o_j
gggglllluuuuUUUUnnnnPPPPrrrroooojjjjeeeecccctttt4444 is equivalent to gggglllluuuuUUUUnnnnPPPPrrrroooojjjjeeeecccctttt when _c_l_i_p_W is 1, _n_e_a_r is 0
and _f_a_r is 1.
NNNNOOOOTTTTEEEESSSS
gggglllluuuuUUUUnnnnPPPPrrrroooojjjjeeeecccctttt4444 is available only if the GLU version is 1.3 or greater.