asCairoDevice          package:cairoDevice          R Documentation

_C_o_n_v_e_r_t_i_n_g _G_T_K+ _w_i_d_g_e_t_s _t_o _C_a_i_r_o _g_r_a_p_h_i_c_s _d_e_v_i_c_e_s

_D_e_s_c_r_i_p_t_i_o_n:

     Allows one to convert an arbitrary realized GTK+ widget (usually a
      'GtkDrawingArea') or a 'GdkDrawable'  (like a 'GdkPixmap') to a
     Cairo graphics  device, so that R plot commands draw to the
     widget/drawable.

_U_s_a_g_e:

     asCairoDevice(widget, pointsize = 10)

_A_r_g_u_m_e_n_t_s:

  widget: The realized widget or drawable to which the R graphics are
          drawn

pointsize: The default font size in the R plot

_D_e_t_a_i_l_s:

     The main purpose of this function is to allow the user to  embed
     an R plot in a GTK user interface constructed with RGtk2. Please 
     see the examples in the RGtk2 package.

     Drawing to an offscreen 'GdkPixmap' is useful for buffering and
     transforming R graphics.  For example, one could copy the pixmap
     to a 'GdkPixbuf' and add a watermark before saving as a gif, png,
     jpg, etc.

_N_o_t_e:

     In previous versions of the package (pre 2.0), it was possible to
     call 'asCairoDevice' on a widget before it was realized. This
     should not have been allowed, because it is impossible to draw to
     an unrealized widget. Many  published examples called
     'asCairoDevice' before realizing the widget, but they will now
     fail with an error. When calling 'asCairoDevice' on a widget,
     first realize the widget, for example by adding the widget to a
     container where the top-level ancestor is visible.

_A_u_t_h_o_r(_s):

     Michael Lawrence

_R_e_f_e_r_e_n_c_e_s:

     <URL: http://www.ggobi.org/rgtk2> <URL: http://www.gtk.org/> <URL:
     http://www.cairographics.org/>

