Querying the Viewport Tree       package:grid       R Documentation

_G_e_t _t_h_e _C_u_r_r_e_n_t _G_r_i_d _V_i_e_w_p_o_r_t (_T_r_e_e)

_D_e_s_c_r_i_p_t_i_o_n:

     'current.viewport()' returns the viewport that Grid is going to
     draw into.

     'current.vpTree' returns the entire Grid viewport tree.

     'current.vpPath' returns the viewport path to the current
     viewport.

     'current.transform' returns the transformation matrix for the
     current viewport.

_U_s_a_g_e:

     current.viewport(vp=NULL)
     current.vpTree(all=TRUE)
     current.vpPath()
     current.transform()

_A_r_g_u_m_e_n_t_s:

      vp: A Grid viewport object.  Use of this argument has been
          deprecated.

     all: A logical value indicating whether the entire viewport tree
          should be returned.

_D_e_t_a_i_l_s:

     If 'all' is 'FALSE' then 'current.vpTree' only returns the subtree
     below the current viewport.

_V_a_l_u_e:

     A Grid viewport object from 'current.viewport' or
     'current.vpTree'.

     'current.transform' returns a 4x4 transformation matrix.

     The viewport path returned by 'current.vpPath' is 'NULL' if the
     current viewport is the 'ROOT' viewport

_A_u_t_h_o_r(_s):

     Paul Murrell

_S_e_e _A_l_s_o:

     'viewport'

_E_x_a_m_p_l_e_s:

     grid.newpage()
     pushViewport(viewport(width=0.8, height=0.8, name="A"))
     pushViewport(viewport(x=0.1, width=0.3, height=0.6,
       just="left", name="B"))
     upViewport(1)
     pushViewport(viewport(x=0.5, width=0.4, height=0.8,
       just="left", name="C"))
     pushViewport(viewport(width=0.8, height=0.8, name="D"))
     current.vpPath()
     upViewport(1)
     current.vpPath()
     current.vpTree()
     current.viewport()
     current.vpTree(all=FALSE)
     popViewport(0)

