NAME
====
  vg_sprite_zoom() - zoom a sprite greater or smaller


SYNOPSIS
========
  sprite * vg_sprite_zoom(sprite * spt, double xmul, double ymul)


DESCRIPTION
===========
  The passed sprite spt is zoomed with a factor of xmul into
  x-direction and a factor of ymul into y-direction,
  which means that all bitmaps of this sprite are zoomed.
  The original size for xmul and ymul is 1.0.
  E.g. using 2.0 for xmul will zoom it twice as big into x-direction.

  Then the modified sprite spt is returned.
  This is another behaviour than vg_bitmap_zoom() shows, which leaves
  the passed bitmap untouched and returns a new static zoomed bitmap.


RETURN VALUE
============
  If it succeeds, a pointer to the zoomed 1.parameter is returned.
  If an error occurs, NULL is returned, an error message is printed to stderr.


SEE ALSO
========
  Index
  Understanding sprites
  vg_sprite_createnew()
  vg_sprite_createfromfile()
  vg_sprite_add()
  vg_sprite_duplicate()
  vg_sprite_rotate()
  vg_sprite_mirror()
  vg_sprite_getnext()
  vg_sprite_getcurrent()
  vg_sprite_reset()
  vg_sprite_free()