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Amiga CD-Sensation - Ausgabe 1 - Demos Are Forever (1996)(GTI - Schatztruhe)(DE)[!].iso
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ES ES
NAME
ES -- EuroStars
SYNOPSIS
ES [MRS][XYZ] <value> [<value> ... ]
ES B
ES Q (ARexx only)
DESCRIPTION
ES is a starfield program based on European code that has been
massively cleaned up and featurized. As a result, it doesn't run
quite as smoothly on vanilla 68000-based systems, but it's less
likely to trash your system.
ES may be run from the command line or from the Workbench. When
you're finished looking, click the left mouse button anywhere on the
starfield to exit.
ES lets you specify how the stars move and rotate. This is done
from the command line or from the ARexx port. For both, the
argument syntax is the same.
ARGUMENTS
The M, R, and S operators specify star movement, rotation, and spin
respectively. Movement specifies how many world units the stars are
translated each frame. Rotation specifies a static/initial rotation
angle. Spin specifies the change in rotation for each frame. The
X, Y, and Z specifiers indicate which axes the operators are to
apply. Rotation angles are specified in "EuroHackerGrads." There
are 2048 EHG to a full 360 degree circle.
The MRS operators must appear before the the XYZ specifiers, and
there may be no spaces between them. Only one MRS operator may
appear before a given set of XYZ specifiers. Following the MRSXYZ
command are the actual values to be used.
It's much easier to understand if you look at the examples.
In addition to the above, there are two additional arguments that
may be used:
B: Operate as background server.
Ordinarily, ES will exit when you click on its screen.
However, if you want to do extensive ARexx operations
without user interference, this option may be specified,
causing ES to ignore all subsequent mouse events on its
screen. Once backgrounded, ES cannot be un-backgrounded.
The only way to terminate a backgrounded ES is with the
following command:
Q: Quit.
When sent as an ARexx command, ES will exit immediately.
This option on the CLI command line is meaningless; if
present, the entire command line is ignored.
AREXX
ES features an ARexx port. The name of the port is EUROSTARS.
Commands sent to this port are exactly the same as those on the
command line. Malformed commands are returned with RC set to
RC_ERROR (10).
Commands are cumulative; that is, a move command (for example)
remains in effect until reset by another move command for the same
axis. Thus, an MX command followed later by an SX command does not
cancel the MX command.
EXAMPLES
ES mx 4
Move stars 4 units along X axis each frame.
ES sxyz 2 -4 6
For each frame, spin the X axis 2 EHG, the Y axis -4 EHG,
and the Z axis 6 EHG.
ES rx 512
Rotate X axis 512 EHG and keep it there.
ES rx -512 sx 2
Start X axis rotated at -512 EHG and add 2 EHG to it each
frame.
ES mxz 10 0 sxyz 2 2 2
Move 10 units along X, zero units along Z, and spin all axes
by two EHG each frame.
ES mxz sxyz 10 0 2 2 2
Identical to the above.
ES sxmxsymzsz 2 10 2 0 2
Again, identical to the above.
As you can see, the syntax is very flexible.
NOTES
Despite its nomenclature, the 'B' option does not fork ES into the
background; you must use the 'Run' command.
The coordinate system is right-handed, X axis horizontal, Y axis
vertical, Z axis perpendicular to the screen. Positive rotations
are clockwise, and are in Z,Y,X order.
The default startup values are:
MX 0 MY 0 MZ 4 RX 0 RY 0 RZ 0 SX 0 SY 0 SZ 0
BUGS
Slow on a 68000. Short of Disable()ing the system or reducing the
number of stars, this is unavoidable.
Malformed commands generate a diagnostic string to the CLI. These
strings are not available to ARexx programs. Sigh...
AUTHOR
Leo L. Schwab -- New Technologies Group, Inc.
BIX: ewhac
Portal: ewhac
InterNet: ewhac@ntg.com ..or.. ewhac@well.sf.ca.us