From 33b31aeadd0c70c5b88f4ef59d02d0814ab013b6 Mon Sep 17 00:00:00 2001
From: Mario Zechner <badlogicgames@gmail.com>
Date: Thu, 6 Oct 2022 16:23:37 +0200
Subject: [PATCH] [ts] Port of commit 3ea4f66. AnimationState, fixed rotation
 mix when direction changes. See #2158.

---
 spine-ts/spine-core/src/AnimationState.ts | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/spine-ts/spine-core/src/AnimationState.ts b/spine-ts/spine-core/src/AnimationState.ts
index 1435960ee..03a020ecd 100644
--- a/spine-ts/spine-core/src/AnimationState.ts
+++ b/spine-ts/spine-core/src/AnimationState.ts
@@ -394,17 +394,21 @@ export class AnimationState {
 				lastTotal = 0;
 				lastDiff = diff;
 			} else {
-				lastTotal = timelinesRotation[i]; // Angle and direction of mix, including loops.
-				lastDiff = timelinesRotation[i + 1]; // Difference between bones.
+				lastTotal = timelinesRotation[i];
+				lastDiff = timelinesRotation[i + 1];
 			}
-			let current = diff > 0, dir = lastTotal >= 0;
-			// Detect cross at 0 (not 180).
-			if (MathUtils.signum(lastDiff) != MathUtils.signum(diff) && Math.abs(lastDiff) <= 90) {
-				// A cross after a 360 rotation is a loop.
-				if (Math.abs(lastTotal) > 180) lastTotal += 360 * MathUtils.signum(lastTotal);
-				dir = current;
+			let loops = lastTotal - lastTotal % 360;
+			total = diff + loops;
+			let current = diff >= 0, dir = lastTotal >= 0;
+			if (Math.abs(lastDiff) <= 90 && MathUtils.signum(lastDiff) != MathUtils.signum(diff)) {
+				if (Math.abs(lastTotal - loops) > 180) {
+					total += 360 * MathUtils.signum(lastTotal);
+					dir = current;
+				} else if (loops != 0)
+					total -= 360 * MathUtils.signum(lastTotal);
+				else
+					dir = current;
 			}
-			total = diff + lastTotal - lastTotal % 360; // Store loops as part of lastTotal.
 			if (dir != current) total += 360 * MathUtils.signum(lastTotal);
 			timelinesRotation[i] = total;
 		}