Decreasing a variable by one

[baggey]

Anyone know, whats the quickest way of doing the above

PlayBASIC Code: [Select]

1:   reghl_=reghl_-1

2:   dec reghl_,1
   
3:   reghl_--

Or should i say whick is the quickest 1,2 or 3  ::)

Kind regards Baggey

[daver]

#3 is less characters. In this case it's the only "quickest way" that matters...IMHO.

If you are in a tight loop doing this a million times I would suggest writing a test harness that gets the time at the start, loops a million times and gets the time at the end. Do this for each scenario and see what result you get.

Will you ask this question when writing your graphics code? That's where performance optimizations will really make a difference.

[kevin]

Or should i say whick is the quickest 1,2 or 3

 In modern versions of PB,  they're all the same operation.  In legacy versions, INC/DEC used to be special case operations, but over time they became slower than standard subtract and add, as such they're recast as sub/add.  

[baggey]

Will you ask this question when writing your graphics code? That's where performance optimizations will really make a difference.

Thanks for the hint  using a timer to wrap code ;)

In most cases i always use the 'C' style operator.

As the Emulator is coming on. Im finding certain approaches create a bottle neck and others seem to whizz on!

The Graphics emulation is already done! Kevin looked over some of my code and its running as fast as we can get it  ;D

So, in a nutshell 'C' style is my preferred approach, and in Playbasic there all the same!

Thanks Peep's!

Baggey

[kevin]

fast as we can get it

  we ? ... no..

[baggey]

You mean it could be faster?

Baggey