Re: please white background

peter Murray-rust (
Sun, 4 Feb 1996 09:59:10 +0000 (GMT)

On Sun, 4 Feb 1996, Choiset-Yvan wrote:

> It s really good and clear.Unfortunately some of representations
are > on black background ,could you put it white it would be better for
> printing.

This is a completely reasonable request,but one that reveals a lot of
history in molecular graphics. The first programs (PLUTO, ORTEP) *were*
deisgned to be printed - normally in monochrome - and used a black pen on
a white background. Graphics screens were expensive and green on black
(because of the phosphor chosen). Then came the high-performance
graphics - first the GT40 (green on black) and then the E&S deveices (MPS
PS2 PS300) all white on black. These were low emittance by modern
standards and often had to be used in a darkened room. The graphics were
vector-driven and the phosphor was only illuminated on the lines
(vector strokes).
The commonest form of 'hardcopy' was to take slides from the screen
and some of these were gorgeous. Printed hardcopy normally required
writing a completely separate program which would try to capture a
representation of the vector strokes - not all programs had hardcopy.
The advent of high-performance raster (ca 1988) would have allowed
white backgrounds, but people chose to continue with black ones. My
guesses for the reason would be:
- the programs couldn't easily be changed
- people still worked in darkened rooms and white screens distracted
others with low emittance
- colour on white didn't have the same aesthetics as colour on black

The course has contributions from many people and the pictures represent
their default usage. Many of these have probably given little though to
the production of hardcopy. I have had exactly the same problem many

- sometimes it's trivial to change the background by using a program
like XV or Lview (this has a colour map and you could change black to
white). But this will only work if there are no other black lines.
- we need a style sheet for authors. I produced one last time (but
I don't think it dealt with this). Many authors donate material
voluntarily, so we can only guide them
- use tools where the client can alter the colour attributes. (e.g.
if there is a rasmol display, then *you* can alter the background

There are many other aspects to a style sheet - e.g. how is material
indexed and this would be a useful discussion to have.


Peter Murray-Rust, Glaxo Research & Dev. (; (BioMOO: PeterMR)
Birkbeck College,, CBMT/Daresbury,