Omnimaga

Calculator Community => Major Community Projects => The Axe Parser Project => Topic started by: Okimoka on December 13, 2016, 01:06:17 pm

Title: Dynamically access variables
Post by: Okimoka on December 13, 2016, 01:06:17 pm

Is there a way to shorten this code?

Code: [Select]

If L=1
 Pt-On(...,Pic1)
End
If L=2
 Pt-On(...,Pic2)
End
If L=3
 Pt-On(...,Pic3)
End
...

I tried accessing the images using memory adresses but it doesn't seem like the Pic variables have constant memory space between them.
Is there a way to evaluate an expression as a variable?
Is this already the most efficient you can get?
Thank you for your help!

Title: Re: Dynamically access variables
Post by: Sorunome on December 13, 2016, 01:09:56 pm

Well, you could do something like

Code: [Select]

Pt-On(....,L=1?Pic1,(L=2?Pic2,(L=3?Pic3))))
Or, preferable, probably a pointer-table, however it slipped my mind right now how to do those in axe....
If you are wondering what that question-mark stuff does: https://derpybot.sorunome.de/axe.php?q=%3F (https://derpybot.sorunome.de/axe.php?q=%3F)

Title: Re: Dynamically access variables
Post by: Okimoka on December 13, 2016, 01:35:49 pm

Very nice, the ternary solution is already so much cleaner!
If I understood right, a pointer-table would require me to write the adresses of all Pic variables into a Buffer first?

Title: Re: Dynamically access variables
Post by: Runer112 on December 13, 2016, 01:48:58 pm

You can do this by writing the addresses of the three sprites into a buffer, yes. The code would look something like this:

Code: [Select]

Pt-On(X,Y,{L*2-2+Data(Pic1ʳ,Pic2ʳ,Pic3ʳ)}ʳ)
However, best would be to declare the sprite data in sequence so each one's data immediately follows the next, which allows this:

Code: [Select]

[0123456789ABCDEF]→Pic1
[FEDCBA9876543210]→Pic2
[FFFFFFFFFFFFFFFF]→Pic3
...
other stuff here
...
Pt-On(X,Y,L*8-8+Pic1)

And a suggestion: in either case, your life would be made easier by using zero-based numbering. That generally translates into simpler/more efficient code. In the first case, you could remove the -2, and in the second case, you could remove the -8.

Title: Re: Dynamically access variables
Post by: Okimoka on December 13, 2016, 03:40:37 pm

Works fantastically, thank you both so much for your time!
I revised the program to use zero-indexing, good hint  :thumbsup:

Title: Re: Dynamically access variables
Post by: Sorunome on December 13, 2016, 03:48:19 pm

Quote from: Runer112 on December 13, 2016, 01:48:58 pm

You can do this by writing the addresses of the three sprites into a buffer, yes. The code would look something like this:

Code: [Select]

Pt-On(X,Y,{L*2-2+Data(Pic1ʳ,Pic2ʳ,Pic3ʳ)}ʳ)
However, best would be to declare the sprite data in sequence so each one's data immediately follows the next, which allows this:

Code: [Select]

[0123456789ABCDEF]→Pic1
[FEDCBA9876543210]→Pic2
[FFFFFFFFFFFFFFFF]→Pic3
...
other stuff here
...
Pt-On(X,Y,L*8-8+Pic1)

And a suggestion: in either case, your life would be made easier by using zero-based numbering. That generally translates into simpler/more efficient code. In the first case, you could remove the -2, and in the second case, you could remove the -8.

You actually only have to name the first block, so that your code looks like this (assuming now you have zero-based numbering):

Code: [Select]

[0123456789ABCDEF]→Pic1
[FEDCBA9876543210
[FFFFFFFFFFFFFFFF
...
other stuff here
...
Pt-On(X,Y,L*8+Pic1)