Replaced loops_current with end_loop in AnimationNodeStateMachinePlayback

[ScottVMariotte]

First time committing to open source!

Fixes #59967

Found in AnimationNodeStateMachinePlayback

Private variable loops_current in was being used in the method _travel to calculate the end of a loop.

if (next_pos < pos_current) {
    loops_current++;
}
pos_current = next_pos; //looped

if (switch_mode == AnimationNodeStateMachineTransition::SWITCH_MODE_AT_END) {
    goto_next = next_xfade >= (len_current - pos_current) || loops_current > 0;

This created an issue when an Advance Condition (atEnd) was changed from false to true when loops_current > 0 (any time after the first loop). This caused an immediate transition instead of at the end of the animation loop.

Could not find any other use for loops_current so I replaced it with end_loop to solve this issue;

Relevent changes in _travel

{ //advance and loop check

	float next_pos = len_current - rem;

-	if (next_pos < pos_current) {
-		loops_current++;
-	}
+	end_loop = next_pos < pos_current;
	pos_current = next_pos; //looped
}


if (switch_mode == AnimationNodeStateMachineTransition::SWITCH_MODE_AT_END) {
-    goto_next = next_xfade >= (len_current - pos_current) || loops_current > 0;
-    if (loops_current > 0) {
+    goto_next = next_xfade >= (len_current - pos_current) || end_loop;
+    if (end_loop) {
......
}

First time contributing please inform me if I did anything out of conduct :)

[ScottVMariotte]

Sorry did not mean to close this... I'm still trying to get used to using GitHub and was confused.... Sorry if I'm making a mess 😅

[akien-mga]

The changes look good style wise, just needs a review from folks familiar with animation features (@godotengine/animation).

[SaracenOne]

Took me a bit to understand the actual issue, but yep, as far as I can tell, seems fine to me, tested it, and it appears to fix the bug.

[akien-mga]

Thanks!

[akien-mga]

Cherry-picked for 3.5.

[akien-mga]

Cherry-picked for 3.4.5.