preLogo
Displays a pre-Desktop Welcome screen.
Version: 1.04 (23 May 2005)
Public Domain software

Latest version is obtainable from
   http://www.argonet.co.uk/users/coleman/


On new PC's they been hidding the boot up sequence of
post tests behind a nice little picture.

Well, anything a PC can do ... So here's the Acorn version.

Whilst this was intended for Risc PC's it should be possible to
run on the other ranges.

To install it
==============
For those with the universal !Boot structure :-
1. Copy the directory preLogo from the archive onto the hard disc
   that you boot from placing it in the !Boot.Utils directory.
2. Rename !Boot.Utils.BootRun as !Boot.Utils.BootRun2
3. Copy BootRun from the archive to the !Boot.Utils directory.

For everyone else :-
1. Install the universal !Boot structure.
2. Install preLogo as above.

That's it; next time you reset the computer you should get the
logo displayed instead of the text that you normally get.
RISC OS 4 and later will get the RISC OS 4 banner, and
pre-RISC OS 4 will get the Acorn nut.

Optional extras
===============
During boot, the pointer is displayed in black which doesn't look
particularly nice, so if you want to stop that then you need to
alter !Boot.Utils.HOn and REM out the *Pointer 1 line.  See the
enclosed HOn in the preLogo directory.
Under Risc OS 3.10 the pointer disappears until you do a
*Pointer 1, so you might not want to mess with HOn in that case,
and the initial pointer in the desktop is black but this cures
itself if you hold down the select or adjust buttons and release
when it changes to a double pointer. (ie. initiate a drag, but dont
actually drag anything), you might also need to put a WimpMode n
in the Desktop file (where n is the mode you want for the desktop).

If you want a different picture then grab, create, alter a sprite
of size 640 x 480 and place in !Boot.Utils.preLogo with filename
Logo or you can simply alter the !Boot.Utils.preLogo.!Run file so that
the variable <preLogo$Logo> points to the Sprite you want.
On pre-Risc PC's the startup mode will depend on your configuration
so you may need to experiment.

Remember this is before PreDesktop has been run so variables and other
modules have probably not been loaded yet.  Which is one reason for not
allowing jpegs as not all computers have the jpeg module in ROM.

How to stop it
==============
1. Hold down either of the Shift keys before the sprite is displayed
   and the sprite will not be displayed. Be careful though because this
   can skip the normal bootup sequence
2. If the preLogo module is missing, then again no picture! Doh!
3. If the file pointed to be <preLogo$Logo> is missing or is not a
   sprite file then no picture

If there is a problem with the Logo sprite file then a message will
be displayed and boot will continue without displaying a picture.

Testing
=======
It has been tested on an StrongARM Risc PC using the universal !Boot
structure on RISCOS 3.50 and 4.02 patch 5.
It has also been tested on an A440/1 running 3.10 using the universal
!Boot structure.

Problems on Boot
================
If there is an error during boot then the picture will be removed and
the error displayed.  There is an error "No more modules" that is
caused by UnplugTbox but this is ignored by preLogo.

Misc
====
The pre-Welcome screen picture is removed if the mode is changed and
when the Desktop is first entered.

On the A440/1 (I am assuming this is because of Risc OS 3.10) when the
desktop welcome banner is displayed, the screen mode isn't changed,
whereas my RiscPC changes into the desktop screen mode before displaying
the desktop banner.  This results in the welcome banner being displayed
on top of the logo, so I have altered the program to clear the screen before
the welcome banner is displayed.

When the screen is cleared the display is black on white, instead of white on
black.  Why this is I don't know, if any can come up with a solution I would 
be most grateful; in the meantime I will keep it in mind as something to fix.

Something else that has come to light recently under RISCOS 4.02 is that some
applications either display a black rectangle on the screen or clear the screen
completely. Version 1.03 fixes this.

The source code is included in the preLogo directory.

History
=======
1.00 (27 Feb 1998)
  First version, written in Basic.

1.01 (07 Mar 1998)
  Assembly code version of the Basic version 1.00

1.02 (09 Mar 1998)
  Tested on an A440/1 running Risc OS 3.10 and added Run$Path line to
  the BootRun file as BootCommands module not in 3.10
  Under Risc OS 3.10 will clear the display before the desktop welcome
  banner is displayed.

1.03 (20 Sep 2000)
  Fixed problem with the screen blanking during errors (found whilst writing
  a BASIC program - took a while to realise it was preLogo and not the other
  program).
  Added preLogo$Logo variable and changed !Run so that RISC OS 4 and later get
  the Pace banner, whilst pre-RISC OS 4 get the Acorn nut.

1.04 (23 May 2005)
  Created preLogo32 module as a 32-bit compatible module so should work on
  32-bit RISC OS.
  !Run amended to load the appropriate module according to Boot$OSVersion.


Any comments then please e-mail me at coleman@argonet.co.uk.
Also if you alter the code then please e-mail me with the details.

Thank you.
Richard Coleman
coleman@argonet.co.uk
