Stargate V1.00

Take out your frustration on the Aliens coming through the Stargates.

Keys are:-
X=Left
Y=Right
Return / Enter = Fire

S=Sound Effect on/off
M=Music on / off
See the intro screen for other information.

Stargate For RISC OS written By Terry Swanborough 20/12/20
Updated to use desktop in 2022


Desktop Display Mode:-

The game should adapt to any desktop display mode.

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MultiTasking :-

Once !Stargate is started it will place an icon on the iconbar.

If you press select on the Iconbar icon a window will open displaying
the !Stargate high score table. See this window for details of which keys to use.
(arrow keys and joystick are also supported.)


If the desktop window focus is moved to another application while you are playing
the main game the game will freeze and wimp polling will be reduced so that the system 
can multitask in a more efficient way.

Stargate is polled at 100Hz PPS (polls per second)  and the FPS (frames per second) 
are simulated so you can get a situation where the PPS are lower than the FPS
this is because Stargate uses an internal timer to regulate the screen update.

Most of the computers I have tried the game on can multitask only the Iyonix needs
to run in full screen to operate at a reasonable speed.

To allow Stargate to work in any screen mode OS_SpriteOP 56 is used to handle the conversion
of the graphics in real time this a slower than single tasking see below:-
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Single Tasking

When you select full screen the game goes into single tasking mode and selects screen
MODE 28 (640x480) 256 colours I have still polled the system at 100Hz but as you are
single tasking the overheads are much lower so this will work better on slower computers.

This mode uses the faster OS_SpriteOP 34 which will give better FPS on slower computers.
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Iconbar Menu Options:-

The menu have the following options.
Info		(Program information window) (iconbar menu only)
Show FPS	(Shows Frames per second and polling speed 100Hz)
Full Screen	(uses MODE 28 (640 x 480) this single tasks.
Scale 1.5 : 1   (960 x 720) size window
Scale 1:1       (640 x 480) size window
Quit            quit the program
Reset Scores	
 
