#I forgot as well
lilac mason
so cool
modern quartz
So yeah, I understand the basics of for loops at the simplest level.
lilac mason
Okay. So, you then say something like this:
for(i = currentCam; i = cameras.Length; i++)
Ok
Oh wait, would I have it in the for loop that if currentCam doesn't have the tag it exits the loop?
lilac mason
this basically says "we're gonna start at the head of the collection (current cam). Every time we finish the block of code, increase i by one. Stop when we get to the end."
{
if(cameras[i].tag == "Locked") continue;
wheat pier
I think you could do if (//doesnt have tag) return; you could stop the entire function at that point "return"
lilac mason
This line (probably messed up some syntax sorry lol) is the guard clause. Continue means you just skip the rest of the block and go to the next iteration
// do stuff
}
sorry, got ahead of myself
modern quartz
Would that not constantly add until its at the end of the array?
modern quartz
sorry
lilac mason
no worries. I'm thinking through the problem myself
ah! Okay. So the issue is that if you're on element [3] of length 6, by you want to loop all the way back to 3 if everything is locked
hmm
that's why I was concerned about the while loop: it assumes at least one camera is unlocked
modern quartz
Or any combination of locked and unlocked. Say there's 6 in an array, I'm at 2, and numbers 3 and 4 are locked. I want to go to 5
lilac mason
but if that assumption is safe, then maybe a while loop IS better
modern quartz
Then if I'm at 5, and 6 and 1 are locked, I want to go to 2
lilac mason
okay so
[
0 => Untagged
1 => Untagged
2 => Untagged (but currentCam points here)
3 => Locked
5 => Untagged // <- next
]
Yeah
lilac mason
Cool. Okay. So instead of using cameras locked status in while condition, we're gonna use the currentCam I think.
modern quartz
What do you mean
lilac mason
yeah hold on lol I already mispoke
xD
I should jsut write in code
while(true)
{
if(cameras[currentCam].tag == "Locked")
{
currentCam++; // skip this camera
continue; // go back to beginning of the loop, skipping the remainder of the loop
}
currentCam++; // get next unlocked camera
if(currentCam == cameras.Length) { currentCam = 0; } // if we are at the end of the array, loop back to zero
break; // exit the loop, ignoring while(true)
}
Does this also just go to the next one normally if there isn't a locked camera?
lilac mason
I THINK this should work lol. It's weird, and "smelly". I would do it a much different way personally, creating a collection class that's dedicated to the process of iterating through things and returning to the beginning, but this might be closest to your skill level. The for loop someone else suggested using % is also great though. Just assume you don't understand modulus.
Oh right. Like I said. While loops are easy to f up lol
erm. editing
there lol
THAT should do it.
lilac mason
ahahahahaha I did a super dumb
edited. I put currentCam = cameras.Length
which means, in the above example array, EVERY loop iteration, currentCam would be 6. Every time. Which is, of course, outside the bounds of the array
double == is a comparison
modern quartz
I did that, and it didn't work.
lilac mason
same thing still?
modern quartz
Yeah
I even tried using a >= comparison
void incCamera()
{
cameras[currentCam].tag = "Untagged";
cameras[currentCam].GetComponent<AudioListener>().enabled = false;
cameras[currentCam].enabled = false;
while (true)
{
if (currentCam == cameras.Length) { currentCam = 0; } // if we are at the end of the array, loop back to zero
if (cameras[currentCam].tag == "Locked")
{
currentCam++; // skip this camera
continue; // go back to beginning of the loop, skipping the remainder of the loop
}
currentCam++;
break;
}
cameras[currentCam].tag = "MainCamera";
cameras[currentCam].GetComponent<AudioListener>().enabled = true;
cameras[currentCam].enabled = true;
}```and the error takes you to which line? presumably cameras[currentCam].tag?
modern quartz
49 which is cs cameras[currentCam].tag = "MainCamera";
lilac mason
oh!
put if (currentCam == cameras.Length) { currentCam = 0; } // if we are at the end of the array, loop back to zero directly above the break instead of at the top of the loop
modern quartz
Now it doesn't skip cameras with the locked tag
lilac mason
grah. I'm genuinely embarassed that I have not figured this out. It should be trivial 😄
modern quartz
I'm sorry
lilac mason
I'm also embarassed by using a while loop. Feels like the wrong answer still
xD
no worries, no worries!
modern quartz
Only reason I use a while loop is because an If loop would only run once and wouldn't help if multiple locked cameras were in a row
modern quartz
It's ok.
lilac mason
cameras = [ // example array
0 => Locked
1 => Untagged // <-- goal
2 => Untagged
3 => Locked
4 => Untagged // <-- head
]
head = 4;
while(true)
{
head = (head + 1) % cameras.Length;
if(cameras[head].tag != "Locked")
{
break;
}
}
okay ima teach you about mod because it's extremely relevant and super common
for jobs like this
modulus is the % sing
sign
modern quartz
What
lilac mason
if head is 4, and cameras.Length is 5, then that one line reads head = (4+1) % 5
i.e. 5 % 5
mod is an operator that gives you a remainder.
modern quartz
ok
lilac mason
imagine 5 divided by 5. It's equal to?
modern quartz
1
lilac mason
what about 6/5
modern quartz
1.2?
lilac mason
good
that can also be expressed as "1 remainder 1"
what do you thing 5/5 would be expressed as with remainders?
modern quartz
1 remainder 0
lilac mason
yep1
!
so, mod tells us what the remainder is. It doesn't care about the first number
5%5 = 0. 10%5 = 0
This is the trick that lets you wrap around a range of numbers
modern quartz
Got it i think
lilac mason
try the code above. replace head with currentCam. I needed to use head because my brain is not wroking lol
just the while loop tho
wait
sorry
modern quartz
Doesn't skip
lilac mason
yeah, had to change it again
have to go to the next camera first, then check for locked status
otherwise head never changes
lol
by the way, i've been dabbling in coding for a decade, and got paid thousands this year for code I deployed. I've always had issues with these kinds of circular arrays
modern quartz
It works. Thank you very much.
lilac mason
YES!
modern quartz
I definitely realized how little I know.
lilac mason
sorry about the back and forth lol
modern quartz
No worries
lilac mason
hahaha okay so while I have you, show me that whole function
modern quartz
void incCamera()
{
disableCam();
while (true)
{
currentCam = (currentCam + 1) % cameras.Length;
if (cameras[currentCam].tag != "Locked")
{
break;
}
}
enableCam();
}
Any ideas how I can modify it for going the other way around? So go from 3 to 2 to 1?
lilac mason
oh cool you already refactored (extracted methods and renamed them). I would advise refactoring this while loop as well. Call it something like "getNextCamera"
(currentCam - 1) % cameras.Length
just change the sign 🙂
modern quartz
Tried that and it doesn't work
modern quartz
Yeah index
lilac mason
wait no, that's not right. -1%5 is still positive
that was me "thinking aloud". Ignore
huh. that really should work. Throw a Debug.Log(currentCam) at the beginning of the loop
modern quartz
I get zero
while (true)
{
Debug.Log(currentCam);
currentCam = (currentCam - 1) % cameras.Length;
if (cameras[currentCam].tag != "Locked")
{
break;
}
}
so, it says zero and then the index out of range?
modern quartz
yes
lilac mason
weird. 0 is the first item in the index
it should never be out of range unless an array is uninitialized
how many cams do you have in the scene?
modern quartz
Currently 5
lilac mason
and how do you get the "cameras" array?
modern quartz
lilac mason
ty one moment
So, just to clarify, on decrement, the Console says 0, then index out of range, and the index out of range points to line 67?
modern quartz
Yes
lilac mason
oh, move the debug.log down underneath the modulus
that "should" be -1 for some reason. Or maybe -4
modern quartz
-1
modern quartz
Yeah?
lilac mason
I've never really had to do negative mods in c# but APPARENTLY it works very differently than an actual modulo because it's a "remainder"
-1 / 5 = 0 remainder -1
which is why it's giving us -1
modern quartz
ok?
lilac mason
this is a common complaint on stack exchange lol
modern quartz
so what's the fix?
lilac mason
so to reverse it you have to write your own ACTUAL modulo function
int mod(int x, int y)
{
return (x % y + y) % y;
}
and then use that instead of %, so currentCam = mod(currentCam - 1, cameras.Length)
I think that should work.
modern quartz
It works. Thanks.