Movement Controls not working HELP

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Summary:

Im not new to Ti-Basic but I'm pretty much self-taught took a break and I'm getting back into but have no idea why it's not working.

Movement Controls not working HELP

The Cow1221 07 Jun 2019 19:37

ClrHome
8→X
4→Y
Output(X,Y,"0
getKey→A
While 1

If A=25
Then
X-1→X
ClrHome
If X=1
Then 2→X

If A=34
Then
X+1→X
If X+8
ClrHome
Then
7→X

If A=24
Then
Y-1→Y
ClrHome
If Y=1
Then
2→Y

If A=26
Then
Y+1→Y
ClrHome
If Y=16
Then
15→Y
End
End
End
End
End
End
End
End
End

Re: Movement Controls not working HELP

(account deleted) 07 Jun 2019 21:01

It looks like there is an If statement inside of another If statement over and over again. This movement routine is severely unoptimized, so this should be an easy fix.

Replace the current code with:

ClrHome
8→X
4→Y
Repeat max(K={45,21,105  ;Checks to see if Clear, Enter, or 2nd is used
Output(Y,X,"O
Repeat K
getKey→K
End
Output(Y,X,"    ;One space, this saves several bytes because there are no ClrHome commands after and in every single If
max(1,min(26,X+(K=26)-(K=24→X
max(1,min(16,Y+(K=34)-(K=25→Y
End  ;Replaces all those other End statements

---

Hewwo, my name is Achak Claw. I was formerly BioHazard.

Re: Movement Controls not working HELP

The Cow1221 07 Jun 2019 23:54

So what ur saying I need to add Ends at the end of all my if statements and not at the end of the program. But I should use what u have down because it is better optimized but sadly I do not understand max and min

Last edited on 08 Jun 2019 01:53 by The Cow1221 Show more

Re: Movement Controls not working HELP

The Cow1221 08 Jun 2019 00:53

I'm starting to understand max and min the thing I don't understand is 1, min in front of (26,X+(K=26)-(K=24→X

Re: Movement Controls not working HELP

Trenly 08 Jun 2019 04:46

max(1,min(26,X+(K=26)-(K=24→X
Following the order of operations, it is evaluated like this:

(K=24 ; This evaluates to either 1 (True) or 0 (False) depending on the value of K
(K=26); This also is either a 1 or 0, depending on the value in K.

Therefore X+(K=26)-(K=24 is best represented by X+[-1,0,1]. This means X plus one of the numbers in the set will be the result. The next command is the min command. This will take the lowest value of the array it is evaluating. By doing min(26,X it is defining the Upper bound of 26. If X is ever greater than 26, the Min command will return 26. If X is lower than 26, it will return X. The max command sets the lower bound. By using max(1,Y it is ensured the result will always be greater than or equal to 1. If Y is greater than 1, Y will be the result. Otherwise, if Y is smaller than 1 the result of the statement will be 1.

By stringing all the parts together, it removes the need for If statements to check for the bounds of the screen.

Re: Movement Controls not working HELP

(account deleted) 09 Jun 2019 18:18

Also, the main part of this problem is simple to figure out. The first If statement checks whether the key (A) is equal to 25. If it is, then only the code for A=25 will be executed. This prevents the other Ifs from working because A will never equal 24, 26, and 34 because the conditions will never met. If A was not equal to 25, nothing still won't work because all the check statements for different key presses are inside one huge If to check for the ↑ key pressed.

---

Hewwo, my name is Achak Claw. I was formerly BioHazard.