


IMVFBCOPY(3IM)         SDSC IMAGE LIBRARY          IMVFBCOPY(3IM)



NAME
     ImVfbCopy - Copy a subarea within a virtual frame buffer

SYNOPSIS
     #include "im.h"

     ImVfb *ImVfbCopy( srcVfb, srcXLeft, srcYTop, srcDX, srcDY, fieldMask, dstVfb, dstXLeft, dstYTop )
          ImVfb *srcVfb ;
          int srcXLeft, srcYTop ;
          int srcDX, srcDY ;
          int fieldMask ;
          ImVfb *dstVfb ;
          int dstXLeft, dstYTop ;


DESCRIPTION
     ImVfbCopy copies a portion of  a  virtual  frame  buffer  to
     another  virtual frame buffer.  A pointer to the destination
     virtual frame buffer is returned.

     _s_r_c_V_f_b is the Vfb whose subarea is to be copied.

     _s_r_c_X_L_e_f_t, _s_r_c_Y_T_o_p indicate the top-left corner of  the  area
     of the Vfb to be copied.

     _s_r_c_D_X, _s_r_c_D_Y are the dimensions of the subarea of the Vfb to
     be copied.

     _f_i_e_l_d_M_a_s_k is a  mask  of  field  constants  (see  ImVfbAlloc
     (3IM))  that  selects the fields in _s_r_c_V_f_b to be copied into
     _d_s_t_V_f_b.

     _d_s_t_V_f_b is the Vfb to receive the copied area.

     _d_s_t_X_L_e_f_t, _d_s_t_Y_T_o_p indicate the top-left corner of  the  area
     to which the subarea will be copied.

NOTES
     If _d_s_t_V_f_b is the constant IMVFBNEW, a new Vfb  is  allocated
     for  the  copied  data.   The  Vfb  has the same size as the
     region being copied, and the fields are selected  by  _f_i_e_l_d_-
     _M_a_s_k.  A pointer to the new Vfb is returned.

     Portions of the copied data that  would  extend  beyond  the
     borders of the _d_s_t_V_f_b are skipped.

     The _s_r_c_V_f_b and _d_s_t_V_f_b may be the same Vfb.  The  source  and
     destination  areas  can  overlap  with  no  unpleasant  side
     effects.

RETURNS
     Upon success, ImVfbCopy returns a pointer to the destination



SDSC              Last change: August 25, 1992                  1






IMVFBCOPY(3IM)         SDSC IMAGE LIBRARY          IMVFBCOPY(3IM)



     Vfb.  Upon failure, IMVFBNULL is returned and ImErrNo set to
     the following:

          IMEMALLOC   Cannot allocate enough memory for the new Vfb

SEE ALSO
     ImVfbIntro  (3IM),  ImVfbErrNo  (3IM),   ImVfbAlloc   (3IM),
     ImVfbDup (3IM)

AUTHORS
     Mike Bailey, Dave Nadeau
     San Diego Supercomputer Center

CONTACT
     SDSC consultants, (619)534-5100, consult@y1.sdsc.edu








































2                 Last change: August 25, 1992               SDSC



