pangoMacros              package:RGtk2              R Documentation

_P_a_n_g_o _C_o_n_v_e_n_i_e_n_c_e _M_a_c_r_o_s

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

     These macros and constants help you layout text with Pango.

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

     pangoAscent(x)
     pangoDescent(x)
     pangoLbearing(x)
     pangoRbearing(x)
     PANGO_SCALE
     pangoPixels(size)
     PANGO_SCALE_LARGE
     PANGO_SCALE_MEDIUM
     PANGO_SCALE_SMALL
     PANGO_SCALE_X_LARGE
     PANGO_SCALE_X_SMALL
     PANGO_SCALE_XX_LARGE
     PANGO_SCALE_XX_SMALL

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

       x: A rectangle describing the glyph extents

    size: A size on the Pango scale

     .

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

     When positioning text, it is beneficial to know the extents of the
     glyphs being drawn. The macros 'pangoAscent', 'pangoDescent',
     'pangoLbearing', and 'pangoRbearing' perform simple math on the 
     given rectangle (representing the glyph extents) to determine the
     corresponding properties. The "ascent" and "descent" are how high
     the glyph extends above and  below the baseline, respectively. The
     "lbearing" and "rbearing" describe the  left-most and right-most
     extents of the glyph.

     The rest are merely constants for scaling. 'PANGO_SCALE' is the
     factor by  which device units are scaled to Pango units. To return
     to device units, use  the 'pangoPixels'. The rest are pre-fab
     factors  for scaling by different degrees.

_V_a_l_u_e:

     The requested quantity in the units of the provided rectangle.

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

     Michael Lawrence

