These are just some tests for working with offscreen bitmaps:

- bitmap.prg:
  Taken from NVDI 2.51. Uses v_opnbm() to draw into a bitmap
  with screen format.

- bitmap2.prg:
  Taken from NVDI 2.51. Uses v_opnbm() to draw into a monochrome
  bitmap.

- openbm.prg:
  Taken from NVDI 5.x. Uses v_open_bm() & vr_transfer_bits. Will not work
  with enhancer, since it needs EdDI >= 1.20

- opnbm.prg:
  Another test for v_opnbm() using screen format. Should draw a blue circle.

- scrninfo.tos:
  Just writes return values from vq_scrninfo() to a file srcninfo.txt


Problems noticed so far:

- the vq_scrninfo() emulated by the (original) enhancer.prg does not set
  the number of intout parameters correctly. It can therefore not be distinguished
  from a vq_extnd() call, which will be done by original VDI if no
  enhancer is installed

- the opnbm.prg displayes a black circle instead of blue when using enhancer

- NVDI 2.5x do not seem to support vq_scrninfo at all. The values returned
  look like the ones returned by vq_extnd(1), and the number of intout parameters
  is set to 45 (but should be 272)

- the documentation on vq_scrninfo() in "neue_fkt.txt" reads that
  intout[0..272] are set (that would be 273 parameters), but only 272
  are described. Original enhancer.prg also sometimes copies 273 values.
  NVDI >= 3.x however reports 272 output values
