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  • Writer's pictureBruce

Main Loop 1 - Shmupkit

I've tried to keep the main loop as simple as possible, I've added a starfield travelling downward using the STAR DOWN command.

Also, I am using T as a 'Trigger' variable, at the moment I'm just using it to trigger updating the score - there's a fuller explanation here:

In most of my games I tend to have a variable used for this purpose, I don't like refreshing scores etc. in every cycle through the program, rather I only want to update the on-screen scores when I need to, and rather than adding 'showscore' in all the events that the score changes, I just use one, wrapped inside a simple IF ... ENDIF and then Trigger it by letting T = 1 in other events.

You can, of course, use this Trigger variable T for other purposes as well in your game, just remember to reset it to 0 when you are done with it.


STAR DOWN			; starfield travelling down

IF T = 1			     ; Score bar update requested
	AT 0 1			; at Line 0 column 1
	SHOWSCORE		; update the score
	LET T = 0		; reset the trigger

IF KEY FIRE3		    ; Pause the game if pause key is pressed

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Hello, I'm Bruce and I write games for old 8bit computers using Jonathan Cauldwell's excellent Multi-Platform Arcade Games Designer (MPAGD)

I've written a few successful* games for the Sinclair ZX Spectrum and MSX platforms that have been (largely) well received including Twenty Four Hour Parsley People scoring a 10 out of 10 on Planeta Sinclair.

In my blog I am sharing lots of the code that I wrote for my games, in a way that you can use in your own games.   I've commented it so that you'll learn some of the techniques I use to create interesting new mechanics and help your games stand out from the pack.

MPAGD includes lots of standard scripts, they're great to get you started, but if you're new (or just rusty) when it comes to writing code, hopefully my tutorials will help you get started and  turn your imagination into awesome 8 bit games!

All my code is free to use and do with as you please, but if you find them useful please feel free to buy me a coffee ...or better still - buy or download my games :)

*successful is a very relative term in 8bit computer games

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