I am trying to get collision working in my SpriteKit game using the didBeginContact function.
My problem is that the function is just not getting called at all when the ball bounces off of the bricks. This is how I have set them both up:
static const uint32_t blockCollisionCheck = 0x1 << 0;
static const uint32_t ballCollisionCheck = 0x1 << 1;
Ball:
SKShapeNode *ball = [[SKShapeNode alloc] init];
CGMutablePathRef drawPath = CGPathCreateMutable();
CGPathAddArc(drawPath, NULL, 0, 0, _ballRadius, 0, M_PI * 2, YES);
ball.path = drawPath;
CGPathRelease(drawPath);
ball.fillColor = [SKColor greenColor];
ball.position = CGPointMake(CGRectGetMidX(self.frame), 150);
ball.name = #"ball";
ball.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:_ballRadius];
ball.physicsBody.friction = 0.0;
ball.physicsBody.restitution = 1.0;
ball.physicsBody.linearDamping = 0.0f;
ball.physicsBody.allowsRotation = NO;
ball.physicsBody.dynamic = YES;
ball.physicsBody.categoryBitMask = ballCollisionCheck;
ball.physicsBody.contactTestBitMask = blockCollisionCheck;
[self addChild:ball];
Bricks:
SKSpriteNode *block = [SKSpriteNode spriteNodeWithColor:[SKColor redColor] size:CGSizeMake(_blockWidth, _blockHeight)];
block.name = #"block";
block.position = CGPointMake(x, y);
block.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:block.size];
block.physicsBody.allowsRotation = NO;
block.physicsBody.friction = 0.0;
block.physicsBody.dynamic = YES;
block.physicsBody.categoryBitMask = blockCollisionCheck;
block.physicsBody.contactTestBitMask = ballCollisionCheck;
[self addChild:block];
I can't for the life of me see what is wrong with this, as I have the category bit masks correct I think? Also both of the sprites are Dynamic, which is another problem I read it could have been.
It's not that the contents of my didBeginContact function is not working, it's just never getting there as evidenced from a lack of NSLog message and breakpoints not being reached.
Any help would be greatly appreciated.
Thank you.
If, as you say, the didBeginContact method is not being called at all, I suspect you did not add the self.physicsWorld.contactDelegate = self; into your GameScene init method.
Related
I have a game where I'm flicking bodies off the screen. I want to detect when these bodies are coming into contact with the edges (still letting the bodies pass through to off the screen) of the screen and I've implemented everything but still it is not working..here's my code:
GameScene.h
typedef NS_OPTIONS(uint32_t, FAPhysicsCategory) {
FAWallCategory = 1 << 0,
FABottomWallCategory = 1 << 1,
FAAnimalCategory = 1 << 2,
};
GameScene : SKScene <SKPhsyicsContactDelegate>
GameScene.m
-(void)setupWorldPhysics
{
// Set world gravity
self.physicsWorld.gravity = CGVectorMake(0.0, -5.0);
float bottomOffset = 400.0;
CGRect newFrame = CGRectMake(0, -bottomOffset, self.frame.size.width, self.frame.size.height + bottomOffset);
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:newFrame];
self.physicsBody.categoryBitMask = FAWallCategory;
self.physicsBody.contactTestBitMask = FAAnimalCategory;
self.physicsBody.collisionBitMask = 0;
}
-(void)launchBody {
SKSpriteNode* animalSprite = [SKSpriteNode spriteNodeWithImageNamed:[animalImagesArray objectAtIndex:animalChoice]];
animalSprite.position = CGPointMake(self.size.width/2, -animalSprite.size.height);
animalSprite.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:25];
animalSprite.physicsBody.dynamic = YES;
animalSprite.physicsBody.allowsRotation = YES;
animalSprite.name = #"animalSprite";
animalSprite.physicsBody.categoryBitMask = FAAnimalCategory;
animalSprite.physicsBody.contactTestBitMask = FAWallCategory;
animalSprite.physicsBody.collisionBitMask = 0;
animalSprite.physicsBody.usesPreciseCollisionDetection = YES;
[self addChild:animalSprite];
}
Alright so it's late and I'm exhausted and I feel like an idiot..i was missing:
self.physicsWorld.contactDelegate = self;
tool
In the following example, there are three things on the screen:
ball (a SKShapeNode)
spriteContainer (a SKSpriteNode that contains ball2, a SKShapeNode)
box (a SKSpriteNode)
Why does ball fall out of view? Does a SKShapeNode need to be inside a SKSpriteNode to have physics properly applied to it?
-(id)initWithSize:(CGSize)size {
if (self = [super initWithSize:size]) {
SKColor * warmRed = [SKColor colorWithRed:0.99 green:0.41 blue:0.25 alpha:1.0];
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:self.frame];
self.backgroundColor = warmRed;
//falls out of view
SKShapeNode * ball = [[SKShapeNode alloc] init];
CGMutablePathRef ballPath = CGPathCreateMutable();
CGPathAddArc(ballPath, NULL, size.width-40, self.size.height/2, 20, 0, M_PI*2, YES);
ball.path = ballPath;
ball.lineWidth = 2;
ball.fillColor = warmRed;
ball.strokeColor = [SKColor whiteColor];
ball.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:20];
[self addChild:ball];
//lands on bottom of screen
SKShapeNode * ball2 = [[SKShapeNode alloc] init];
CGMutablePathRef ball2Path = CGPathCreateMutable();
CGPathAddArc(ball2Path, NULL, 0, 0, 20, 0, M_PI*2, YES);
ball2.path = ball2Path;
ball2.lineWidth = 2;
ball2.fillColor = warmRed;
ball2.strokeColor = [SKColor whiteColor];
CGSize spriteContainerSize = CGSizeMake(40,40);
CGPoint spriteContainerPosition = CGPointMake(size.width/2, size.height/2);
SKSpriteNode * spriteContainer = [SKSpriteNode spriteNodeWithColor:[SKColor blackColor] size:spriteContainerSize];
spriteContainer.position = spriteContainerPosition;
spriteContainer.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:spriteContainerSize];
[spriteContainer addChild:ball2];
[self addChild:spriteContainer];
//lands on bottom of screen
CGSize boxSize = CGSizeMake(40,40);
CGPoint boxPosition = CGPointMake(boxSize.width, size.height/2);
SKSpriteNode * box = [SKSpriteNode spriteNodeWithColor:[SKColor blackColor] size:boxSize];
box.position = boxPosition;
box.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:boxSize];
[self addChild:box];
}
return self;
}
Screenshot:
https://dl.dropboxusercontent.com/u/164157126/example.jpg
Note that you don't set a position for the node which falls off the screen, but set a position for the other two nodes you create.
The default position of a node is 0,0. Your ball will appear at the bottom left of the scene, and since it is over the edge body you defined, will fall off immediately.
Set the ball's position appropriately so that it does not intersect the edge of the screen, and the ball will not fall off.
in my code I have physics bodies set up for ball and welding sprites.
here is the physicsBody setup for ball sprites:
ball.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:10];
ball.physicsBody.affectedByGravity = NO;
ball.physicsBody.velocity = velocity;
ball.physicsBody.restitution = 1;
ball.physicsBody.friction = 0;
ball.physicsBody.categoryBitMask = ballCategory;
ball.physicsBody.collisionBitMask = ballCategory | barrierCategory | weldCategory | weldPointCategory;
ball.physicsBody.contactTestBitMask = weldingCategory;
and this is the physicsBody setup for welding sprites:
weldRU = [SKSpriteNode spriteNodeWithColor:[UIColor redColor] size:CGSizeMake(2, 2)];
weldRU.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:weldRU.size];
//weldRU.physicsBody.dynamic = NO;
weldRU.physicsBody.affectedByGravity = NO;
weldRU.physicsBody.categoryBitMask = weldingCategory;
weldRU.physicsBody.collisionBitMask = 0;
weldRU.physicsBody.contactTestBitMask = ballCategory;
weldRU.physicsBody.usesPreciseCollisionDetection = YES;
in the setup I give each other categoryBitMask's and contactTestBitMask's but the contact override method never gets called when these bodies come in contact. the welding sprites do have actions running at any possible contact time but the physicsBody is always present. So am I missing something that is causing them to not detect contact?
I want to make a soccer ball by IOS SpriteKit
I was able to create a ball in the code such as the following.
However, it does not bounce at all.
To make rebound rate, How can I do this?
(UITouch *touch in touches) {
SKSpriteNode *sprite = [SKSpriteNode spriteNodeWithImageNamed:#"Ball"];
sprite.position = location;
const CGFloat radius = 20.0f;
SKPhysicsBody *pbody = [SKPhysicsBody bodyWithCircleOfRadius:radius];
sprite.physicsBody = pbody;
sprite.size = (CGSize){radius * 2, radius * 2};
sprite.physicsBody.linearDamping=0.12f;
[self addChild:sprite];
}
I have declared like this.
-(id)initWithSize:(CGSize)size {
if (self = [super initWithSize:size]) {
self.backgroundColor = [SKColor colorWithRed:0.15 green:0.15 blue:0.3 alpha:1.0];
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:(CGRect){CGPointZero, size}];
self.physicsWorld.gravity=CGVectorMake(0, -100);
}
return self;
}
This looks like a ball to me
- (void) soccerBallExample
{
// the world bounds
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:CGRectMake(0, 0, self.size.width, self.size.height)];
// the ball
SKShapeNode *ball;
ball = [[SKShapeNode alloc] init];
CGMutablePathRef myPath = CGPathCreateMutable();
CGPathAddArc(myPath, NULL, 0,0, 30, 0, M_PI*2, YES);
ball.path = myPath;
CGPathRelease(myPath);
ball.fillColor = [SKColor blueColor];
ball.position = CGPointMake(200, 200);
[self addChild:ball];
// set the physics
ball.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:30];
ball.physicsBody.restitution = 0.8;
}
In your example, you use a sprite so for radius use
// ball.size.width * 0.5;
I'm testing out pin joints with Sprite Kit, and I'm finding something unusual happening.
My desired setup is this: one wide, flat box, and two circles; the circles are connected via SKPhysicsPinJoints to the box, so they can act as wheels.
Here's my code. I've tried to make it as concise as possible:
- (SKNode*) createWheelWithRadius:(float)wheelRadius {
CGRect wheelRect = CGRectMake(-wheelRadius, -wheelRadius, wheelRadius*2, wheelRadius*2);
SKShapeNode* wheelNode = [[SKShapeNode alloc] init];
wheelNode.path = [UIBezierPath bezierPathWithOvalInRect:wheelRect].CGPath;
wheelNode.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:wheelRadius];
return wheelNode;
}
- (void) createCar {
// Create the car
SKSpriteNode* carNode = [SKSpriteNode spriteNodeWithColor:[SKColor yellowColor] size:CGSizeMake(150, 50)];
carNode.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:carNode.size];
carNode.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
[self addChild:carNode];
// Create the left wheel
SKNode* leftWheelNode = [self createWheelWithRadius:30];
leftWheelNode.position = CGPointMake(carNode.position.x-80, carNode.position.y);
[self addChild:leftWheelNode];
// Create the right wheel
SKNode* rightWheelNode = [self createWheelWithRadius:30];
rightWheelNode.position = CGPointMake(carNode.position.x+80, carNode.position.y);
[self addChild:rightWheelNode];
// Attach the wheels to the body
CGPoint leftWheelPosition = leftWheelNode.position;
CGPoint rightWheelPosition = rightWheelNode.position;
SKPhysicsJointPin* leftPinJoint = [SKPhysicsJointPin jointWithBodyA:carNode.physicsBody bodyB:leftWheelNode.physicsBody anchor:leftWheelPosition];
SKPhysicsJointPin* rightPinJoint = [SKPhysicsJointPin jointWithBodyA:carNode.physicsBody bodyB:rightWheelNode.physicsBody anchor:rightWheelPosition];
[self.physicsWorld addJoint:leftPinJoint];
[self.physicsWorld addJoint:rightPinJoint];
}
What I'm expecting is that the pin joints are anchored at their centre points; however, when I test this, the anchors for the joints appear to be far off.
Am I missing something really obvious?
I also had this issue and the cause is setting the physics body before setting the sprites position.
carNode.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:carNode.size];
carNode.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
Change the above to
carNode.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
carNode.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:carNode.size];
It should work. Thanks Smick.
SpriteKit: How to create Basic Physics Joints
Try this code, I used yours and got weird issues, so started from scratch.
- (SKShapeNode*) makeWheel
{
SKShapeNode *wheel = [[SKShapeNode alloc] init];
CGMutablePathRef myPath = CGPathCreateMutable();
CGPathAddArc(myPath, NULL, 0,0, 16, 0, M_PI*2, YES);
wheel.path = myPath;
return wheel;
}
- (void) createCar
{
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:CGRectMake(0, 0, self.size.width, self.size.height)];
// 1. car body
SKSpriteNode *carBody = [SKSpriteNode spriteNodeWithColor:[UIColor whiteColor] size:CGSizeMake(120, 8)];
carBody.position = CGPointMake(200, 200);
carBody.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:carBody.size];
[self addChild:carBody];
// 2. wheels
SKShapeNode *leftWheel = [self makeWheel];
leftWheel.position = CGPointMake(carBody.position.x - carBody.size.width / 2, carBody.position.y);
leftWheel.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:16];
[self addChild:leftWheel];
SKShapeNode *rightWheel = [self makeWheel];
rightWheel.position = CGPointMake(carBody.position.x + carBody.size.width / 2, carBody.position.y);
rightWheel.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:16];
[self addChild:rightWheel];
// 3. Join wheels to car
[self.physicsWorld addJoint:[SKPhysicsJointPin jointWithBodyA:carBody.physicsBody bodyB:leftWheel.physicsBody anchor:leftWheel.position]];
[self.physicsWorld addJoint:[SKPhysicsJointPin jointWithBodyA:carBody.physicsBody bodyB:rightWheel.physicsBody anchor:rightWheel.position]];
// 4. drive car
[carBody.physicsBody applyForce:CGVectorMake(10, 0)];
}