Goto routines . . .

[DrewPee]

Hello
I am in the process of writing a very basic game to test some drawing routines I am messing about with . . . I am stuck with re-starting a game once you die.
Do I need to use something like a goto command or is there something else I can use in Freebasic?

When I try to use goto I keep on getting this error

94: Branching to other functions or to module-level, to label: strt

Thanks in anticipation

DrewPee

[Shockwave]

There's no need to use commands like Goto nowadays Drewpee.

You could structure your game code something like this;

Code Select Expand


QUIT  = 0
GAME = 0

MAIN LOOP (LOOPS UNTIL QUIT=1)
    IF QUIT = 0 THEN HANDLE TITLE SCREEN SUB
    IF GAME=1 THEN HANDLE GAME SUB
END OF MAIN LOOP

END PROGRAM


HANDLE GAME SUB
START OF LOOP UNTIL GAME=0
   CALL GAME SUBS
   UPDATE SCREEN
   IF DEAD THEN GAME=0
END OF LOOP UNTIL GAME=0
END OF HANDLE GAME SUB



HANDLE TITLE SCREEN SUB
START OF LOOP UNTIL GAME=1
   CALL TITLE SCREEN SUBS
   UPDATE SCREEN
   IF START BUTTON PRESSED THEN GAME=1
   IF QUIT BUTTON PRESSED THEN QUIT=1
END OF LOOP UNTIL GAME=1 OR QUIT=1
END OF HANDLE TITLE SCREEN SUB



[DrewPee]

Shockwave, thanks (as always for your help!),

code removed for now - due to odd problems with some of it - I will re-post at a later date

DrewPee

[DrewPee]

Meant to say - this is still early code so there are bits in there that are not needed etc.

[Shockwave]

You need to understand what happens to the stack.

You branch to a sub and the memory address is stored
when the end sub is encountered, you go back to that last address.

Using goto the way you have in a sub potentially could cause a stack overflow which is why it's terrible programming practice and why freebasic wont let you do it.

The technique I posted is very simple to impliment, why not have a try yourself and post back if you run into problems.

Seriously, forget about goto, there is no need to use it... ever.

[DrewPee]

Thanks Shockwave I will go and try it again.

[Shockwave]

Good luck mate

[DrewPee]

I have figured it out a little more and this is where I am at the moment - still early days but playable now!

@Shockwave - thanks again for your help!

btw - the highest score so far is 2392, not by me I might add, by one of our members on RCM!

Drew

[Shockwave]

It looks pretty cool indeed

The only flaw I can see is the method you used to detect your keypresses causes a delay in movement...

Use this method instead..

IF GETASYNCKEYSTATE( VK_UP ) Then do stuff.

[Hotshot]

very good.....Original game

GOTO is horrible but have you thought about using Select case?

[Shockwave]

Select Case will not help here Hotshot, you'd use Selest Case the same as switch or if and then.

He just needs to have some controling subs and a containing loop.

[DrewPee]

I am still 'cheating' a little - but it does work much better now . . . I have added some music, difficulty levels etc.

.exe attached

[Shockwave]

Still has the slightly annoying movement delay when pressing a key (see above for the solution) but apart from that it's not bad at all.

It's great to see you doing some programming again Drewpee, you should do more but I guess that it's hard to get the time these days.

[DrewPee]

I am using the commands you mentioned, I think I just have them in the wrong place - need to move the code around a little me thinks!

[Shockwave]

You should use GETASYNCKEYSTATE
Like this:

IF GETASYNCKEYSTATE( VK_UP ) THEN

(without the =-32768 bit), that why the controls are slightly broken atm.

[Clyde]

If you are going the Select Case route, if you use Select Case As Const Choice

Choice being a variable of your choice ( hehe, get it ) it's apparently better / faster.