WIP

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

@@ -611,10 +611,11 @@ public class Bone implements Updatable {
 	public void rotateWorld (float degrees) {
 		degrees *= degRad;
 		float sin = sin(degrees), cos = cos(degrees);
-		a = cos * a - sin * c;
-		b = cos * b - sin * d;
-		c = sin * a + cos * c;
-		d = sin * b + cos * d;
+		float ra = a, rb = b;
+		a = cos * ra - sin * c;
+		b = cos * rb - sin * d;
+		c = sin * ra + cos * c;
+		d = sin * rb + cos * d;
 	}
 
 	// ---

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

@@ -47,8 +47,8 @@ import com.esotericsoftware.spine.attachments.PathAttachment;
  * <p>
  * See <a href="http://esotericsoftware.com/spine-path-constraints">Path constraints</a> in the Spine User Guide. */
 public class PathConstraint implements Updatable {
-	static private final int NONE = -1, BEFORE = -2, AFTER = -3;
-	static private final float epsilon = 0.00001f;
+	static final int NONE = -1, BEFORE = -2, AFTER = -3;
+	static final float epsilon = 0.00001f;
 
 	final PathConstraintData data;
 	final Array<Bone> bones;
@@ -122,12 +122,8 @@ public class PathConstraint implements Updatable {
 				for (int i = 0, n = spacesCount - 1; i < n; i++) {
 					Bone bone = (Bone)bones[i];
 					float setupLength = bone.data.length;
-					if (setupLength < epsilon)
-						lengths[i] = 0;
-					else {
-						float x = setupLength * bone.a, y = setupLength * bone.c;
-						lengths[i] = (float)Math.sqrt(x * x + y * y);
-					}
+					float x = setupLength * bone.a, y = setupLength * bone.c;
+					lengths[i] = (float)Math.sqrt(x * x + y * y);
 				}
 			}
 			Arrays.fill(spaces, 1, spacesCount, spacing);

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

@@ -42,7 +42,8 @@ import com.esotericsoftware.spine.PhysicsConstraintData.SpringData;
  * <p>
  * See <a href="http://esotericsoftware.com/spine-physics-constraints">Physics constraints</a> in the Spine User Guide. */
 public class PhysicsConstraint implements Updatable {
-	static final Vector2 temp = new Vector2();
+	static private final Vector2 temp = new Vector2();
+	static private final float epsilon = 0.00001f;
 
 	final PhysicsConstraintData data;
 	final Array<Node> nodes;
@@ -153,6 +154,13 @@ public class PhysicsConstraint implements Updatable {
 		if (mix == 1) {
 			for (int i = 0; i < nodeCount; i++) {
 				Node node = (Node)nodes[i];
+
+				// BOZO
+				if (node.parentBone != null) {
+					node.parentBone.rotateWorld(node.offset);
+					node.parentBone.updateAppliedTransform();
+				}
+
 				Object[] bones = node.bones;
 				for (int ii = 0, nn = bones.length; ii < nn; ii++) {
 					Bone bone = (Bone)bones[ii];
@@ -267,6 +275,9 @@ public class PhysicsConstraint implements Updatable {
 
 		public float massInverse, vx, vy;
 
+		public boolean reset;
+		public float offset, velocity, wx, wy;
+
 		Node (NodeData data) { // Editor.
 			this.data = data;
 		}
@@ -299,9 +310,48 @@ public class PhysicsConstraint implements Updatable {
 			y = data.y;
 			vx = 0;
 			vy = 0;
+
+			offset = 0;
+			velocity = 0;
+			reset = true;
 		}
 
 		public void step (PhysicsConstraint constraint) {
+			// BOZO
+			if (parentBone != null) {
+				float strength = 0.1f;
+				float damping = 0.9f;
+				float wind = 0;
+				float gravity = 0;// -0.0048f;
+				float mass = 4;
+
+				float length = parentBone.data.length, x = length * parentBone.a, y = length * parentBone.c;
+				length = (float)Math.sqrt(x * x + y * y);
+
+				float r = atan2(parentBone.c, parentBone.a) - offset * degRad;
+				float cos = (float)Math.cos(r), sin = (float)Math.sin(r);
+				{
+					float tx = parentBone.worldX + length * cos, ty = parentBone.worldY + length * sin;
+					if (reset)
+						reset = false;
+					else {
+						if (wx - tx != 0 || wy - ty != 0) {
+							float diff = new Vector2(length, 0).rotateRad(r).add(wx - parentBone.worldX, wy - parentBone.worldY)
+								.angleRad() - r;
+							offset += diff * radDeg;
+						}
+					}
+					wx = tx;
+					wy = ty;
+				}
+
+				velocity += ((((offset % 360) + 540) % 360) - 180) * strength / mass;
+				r += offset * degRad;
+				velocity += (length * sin * wind - length * cos * gravity) * mass;
+				offset -= velocity;
+				velocity *= damping;
+			}
+
 			if (parentBone != null) return;
 			x += vx;
 			y += vy;

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

@@ -347,35 +347,40 @@ public class Skeleton {
 		int nodeCount = constraint.nodes.size;
 		for (int i = 0; i < nodeCount; i++) {
 			Node node = (Node)nodes[i];
-			if (node.parentBone != null) sortBone(node.parentBone);
-			for (Bone bone : node.bones)
-				sortBone(bone);
+			sortBone(node.parentBone);
+// for (Bone bone : node.bones)
+// sortBone(bone);
 		}
 
 		updateCache.add(constraint);
 
 		for (int i = 0; i < nodeCount; i++) {
 			Node node = (Node)nodes[i];
-			for (Bone bone : node.bones)
-				sortReset(bone.children);
-		}
-		for (int i = 0; i < nodeCount; i++) {
-			Node node = (Node)nodes[i];
-			for (Bone bone : node.bones)
-				bone.sorted = true;
+			sortReset(node.parentBone.children);
 		}
 
-		Object[] springs = constraint.springs.items;
-		for (int i = 0, n = constraint.springs.size; i < n; i++) {
-			Spring spring = (Spring)springs[i];
-			if (spring.bone == null) continue;
-			sortBone(spring.bone);
-			updateCache.add(spring);
-			sortReset(spring.bone.children);
-			spring.bone.sorted = true;
-			for (Bone child : spring.bone.children)
-				sortBone(child);
-		}
+// for (int i = 0; i < nodeCount; i++) {
+// Node node = (Node)nodes[i];
+// for (Bone bone : node.bones)
+// sortReset(bone.children);
+// }
+// for (int i = 0; i < nodeCount; i++) {
+// Node node = (Node)nodes[i];
+// for (Bone bone : node.bones)
+// bone.sorted = true;
+// }
+//
+// Object[] springs = constraint.springs.items;
+// for (int i = 0, n = constraint.springs.size; i < n; i++) {
+// Spring spring = (Spring)springs[i];
+// if (spring.bone == null) continue;
+// sortBone(spring.bone);
+// updateCache.add(spring);
+// sortReset(spring.bone.children);
+// spring.bone.sorted = true;
+// for (Bone child : spring.bone.children)
+// sortBone(child);
+// }
 	}
 
 	private void sortBone (Bone bone) {