Fixing an issue with rotating a physics enabled node.

Former-commit-id: 94bcf9b

Author: slembcke

UnitTests/CCPhysicsTests.m

@@ -307,7 +307,7 @@ -(void)testBasicSequences9
 
 	TestBasicSequenceHelper(self, physicsNode, parent, node, body);
 }
-	
+
 -(void)testBasicSequences10
 {
 	CCPhysicsNode *physicsNode = [CCPhysicsNode node];
@@ -333,6 +333,74 @@ -(void)testBasicSequences10
 	TestBasicSequenceHelper(self, physicsNode, parent, node, body);
 }
 
+-(void)testBasicSequences11
+{
+	CCPhysicsNode *physicsNode = [CCPhysicsNode node];
+	
+	CCNode *parent = [CCNode node];
+	parent.contentSize = CGSizeMake(25, 35);
+	parent.anchorPoint = ccp(0.3, 0.7);
+	parent.position = ccp(20, 60);
+	parent.rotation = -15;
+	parent.scaleX = 1.5;
+	parent.scaleY = 8.0;
+	
+	CCNode *node = [CCNode node];
+	node.contentSize = CGSizeMake(30, 30);
+	node.anchorPoint = ccp(0,0);
+	node.position = ccp(100, 100);
+	node.rotation = 30;
+	node.scaleX = 2.0;
+	node.scaleY = 3.0;
+	
+	CCPhysicsBody *body = [CCPhysicsBody bodyWithCircleOfRadius:1.0 andCenter:CGPointZero];
+	body.type = CCPhysicsBodyTypeStatic;
+	
+	TestBasicSequenceHelper(self, physicsNode, parent, node, body);
+}
+
+-(void)testDynamicAnchorPoint
+{
+	CCPhysicsNode *physicsNode = [CCPhysicsNode node];
+	
+	CCNode *node = [CCNode node];
+	node.contentSize = CGSizeMake(2, 2);
+	node.anchorPoint = ccp(0.5, 0.5);
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+	
+	node.physicsBody = [CCPhysicsBody bodyWithCircleOfRadius:1.0 andCenter:CGPointZero];
+	node.physicsBody.type = CCPhysicsBodyTypeDynamic;
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+	
+	[physicsNode addChild:node];
+	[physicsNode onEnter];
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+	
+	node.rotation = 90;
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+}
+
+-(void)testStaticAnchorPoint
+{
+	CCPhysicsNode *physicsNode = [CCPhysicsNode node];
+	
+	CCNode *node = [CCNode node];
+	node.contentSize = CGSizeMake(2, 2);
+	node.anchorPoint = ccp(0.5, 0.5);
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+	
+	node.physicsBody = [CCPhysicsBody bodyWithCircleOfRadius:1.0 andCenter:CGPointZero];
+	node.physicsBody.type = CCPhysicsBodyTypeStatic;
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+	
+	[physicsNode addChild:node];
+	[physicsNode onEnter];
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+	
+	node.rotation = 90;
+	XCTAssert(ccpDistance(node.position, CGPointZero) == 0.0, @"");
+}
+
 -(void)testCollisionGroups
 {
 	CCPhysicsNode *physicsNode = [CCPhysicsNode node];

cocos2d/CCNode.m

@@ -222,7 +222,11 @@ -(void) setRotation: (float)newRotation
 {
 	CCPhysicsBody *body = GetBodyIfRunning(self);
 	if(body){
+		CGPoint position = self.position;
 		body.absoluteRadians = -CC_DEGREES_TO_RADIANS(newRotation + NodeToPhysicsRotation(self.parent));
+		
+		// Rotating the body will cause the node to move unless the CoG is the same as the anchor point.
+		self.position = position;
 	} else {
 		_rotationalSkewX = newRotation;
 		_rotationalSkewY = newRotation;