[libgdx] Constraints only updateLocalTransform when necessary.

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/BoneLocal.java

@@ -36,9 +36,6 @@ public class BoneLocal implements Pose<BoneLocal> {
 	float x, y, rotation, scaleX, scaleY, shearX, shearY;
 	Inherit inherit;
 
-	BoneLocal () {
-	}
-
 	public void set (BoneLocal pose) {
 		if (pose == null) throw new IllegalArgumentException("pose cannot be null.");
 		x = pose.x;

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/BonePose.java

@@ -16,9 +16,7 @@ public class BonePose extends BoneLocal implements Update {
 	float a, b, worldX;
 	float c, d, worldY;
 	int update;
-
+	boolean localDirty;
-	BonePose () {
-	}
 
 	/** Called by {@link Skeleton#updateCache()} to compute the world transform, if needed. */
 	public void update (Skeleton skeleton, Physics physics) {
@@ -31,6 +29,7 @@ public class BonePose extends BoneLocal implements Update {
 	 * Runtimes Guide. */
 	public void updateWorldTransform (Skeleton skeleton) {
 		update = skeleton.update;
+		localDirty = false;
 
 		if (bone.parent == null) { // Root bone.
 			float sx = skeleton.scaleX, sy = skeleton.scaleY;
@@ -140,6 +139,7 @@ public class BonePose extends BoneLocal implements Update {
 	 * calling this method is equivalent to the local transform used to compute the world transform, but may not be identical. */
 	public void updateLocalTransform (Skeleton skeleton) {
 		update = skeleton.update;
+		localDirty = false;
 
 		if (bone.parent == null) {
 			x = worldX - skeleton.x;
@@ -218,6 +218,12 @@ public class BonePose extends BoneLocal implements Update {
 		}
 	}
 
+	/** When true, the world transform has been modified and the local transform no longer matches. Call
+	 * {@link #updateLocalTransform(Skeleton)} before using the local transform. */
+	public boolean isLocalDirty () {
+		return localDirty;
+	}
+
 	/** Part of the world transform matrix for the X axis. If changed, {@link #updateLocalTransform(Skeleton)} should be called. */
 	public float getA () {
 		return a;

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/IkConstraint.java

@@ -114,6 +114,7 @@ public class IkConstraint extends Constraint<IkConstraint, IkConstraintData, IkC
 	static public void apply (Skeleton skeleton, BonePose bone, float targetX, float targetY, boolean compress, boolean stretch,
 		boolean uniform, float alpha) {
 		if (bone == null) throw new IllegalArgumentException("bone cannot be null.");
+		if (bone.localDirty) bone.updateLocalTransform(skeleton);
 		BonePose p = bone.bone.parent.applied;
 		float pa = p.a, pb = p.b, pc = p.c, pd = p.d;
 		float rotationIK = -bone.shearX - bone.rotation, tx, ty;
@@ -176,6 +177,8 @@ public class IkConstraint extends Constraint<IkConstraint, IkConstraintData, IkC
 		if (parent == null) throw new IllegalArgumentException("parent cannot be null.");
 		if (child == null) throw new IllegalArgumentException("child cannot be null.");
 		if (parent.inherit != Inherit.normal || child.inherit != Inherit.normal) return;
+		if (parent.localDirty) parent.updateLocalTransform(skeleton);
+		if (child.localDirty) child.updateLocalTransform(skeleton);
 		float px = parent.x, py = parent.y, psx = parent.scaleX, psy = parent.scaleY, csx = child.scaleX;
 		int os1, os2, s2;
 		if (psx < 0) {

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/PathConstraint.java

@@ -196,7 +196,7 @@ public class PathConstraint extends Constraint<PathConstraint, PathConstraintDat
 				bone.c = sin * a + cos * c;
 				bone.d = sin * b + cos * d;
 			}
-			bone.updateLocalTransform(skeleton);
+			bone.localDirty = true;
 			bone.bone.resetUpdate(skeleton);
 		}
 	}

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/PhysicsConstraint.java

@@ -263,7 +263,7 @@ public class PhysicsConstraint extends Constraint<PhysicsConstraint, PhysicsCons
 			tx = l * bone.a;
 			ty = l * bone.c;
 		}
-		bone.updateLocalTransform(skeleton);
+		bone.localDirty = true;
 		bone.bone.resetUpdate(skeleton);
 	}
 

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/Slider.java

@@ -53,14 +53,25 @@ public class Slider extends Constraint<Slider, SliderData, SliderPose> {
 
 	public void update (Skeleton skeleton, Physics physics) {
 		if (pose.mix == 0) return;
-		SliderPose pose = applied;
-		data.animation.apply(skeleton, pose.time, pose.time, false, null, pose.mix, MixBlend.replace, MixDirection.in, true);
 
 		Timeline[] timelines = data.animation.timelines.items;
 		int timelineCount = data.animation.timelines.size;
 		Bone[] bones = skeleton.bones.items;
-		for (int i = 0; i < timelineCount; i++)
+		if (pose.mix == 1) {
-			if (timelines[i] instanceof BoneTimeline boneTimeline) bones[boneTimeline.getBoneIndex()].resetUpdate(skeleton);
+			for (int i = 0; i < timelineCount; i++)
+				if (timelines[i] instanceof BoneTimeline timeline) bones[timeline.getBoneIndex()].resetUpdate(skeleton);
+		} else {
+			for (int i = 0; i < timelineCount; i++) {
+				if (timelines[i] instanceof BoneTimeline timeline) {
+					Bone bone = bones[timeline.getBoneIndex()];
+					bone.resetUpdate(skeleton);
+					if (bone.applied.localDirty) bone.applied.updateLocalTransform(skeleton);
+				}
+			}
+		}
+
+		SliderPose pose = applied;
+		data.animation.apply(skeleton, pose.time, pose.time, false, null, pose.mix, MixBlend.replace, MixDirection.in, true);
 	}
 
 	void sort (Skeleton skeleton) {
@@ -68,7 +79,7 @@ public class Slider extends Constraint<Slider, SliderData, SliderPose> {
 		int timelineCount = data.animation.timelines.size;
 		Bone[] bones = skeleton.bones.items;
 		for (int i = 0; i < timelineCount; i++)
-			if (timelines[i] instanceof BoneTimeline boneTimeline) skeleton.sortBone(bones[boneTimeline.getBoneIndex()]);
+			if (timelines[i] instanceof BoneTimeline timeline) skeleton.sortBone(bones[timeline.getBoneIndex()]);
 
 		skeleton.updateCache.add(this);
 

spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/TransformConstraint.java

@@ -68,16 +68,18 @@ public class TransformConstraint extends Constraint<TransformConstraint, Transfo
 			&& pose.mixShearY == 0) return;
 
 		TransformConstraintData data = this.data;
-		boolean localFrom = data.localSource, localTarget = data.localTarget, additive = data.additive, clamp = data.clamp;
+		boolean localSource = data.localSource, localTarget = data.localTarget, additive = data.additive, clamp = data.clamp;
 		BonePose source = this.source.applied;
+		if (localSource && source.localDirty) source.updateLocalTransform(skeleton);
 		FromProperty[] fromItems = data.properties.items;
 		int fn = data.properties.size;
 		BonePose[] bones = this.bones.items;
 		for (int i = 0, n = this.bones.size; i < n; i++) {
 			BonePose bone = bones[i];
+			if (localTarget && bone.localDirty) bone.updateLocalTransform(skeleton);
 			for (int f = 0; f < fn; f++) {
 				FromProperty from = fromItems[f];
-				float value = from.value(data, source, localFrom) - from.offset;
+				float value = from.value(data, source, localSource) - from.offset;
 				ToProperty[] toItems = from.to.items;
 				for (int t = 0, tn = from.to.size; t < tn; t++) {
 					ToProperty to = toItems[t];
@@ -95,8 +97,8 @@ public class TransformConstraint extends Constraint<TransformConstraint, Transfo
 			}
 			if (localTarget)
 				bone.updateWorldTransform(skeleton);
-			else
+			else 
-				bone.updateLocalTransform(skeleton);
+				bone.localDirty = true;
 			bone.bone.resetUpdate(skeleton);
 		}
 	}