I'm trying to learn SpriteKit. I have a balloon (SKSpriteNode) that after running a SKAction for resizing, the balloon will change its size. the balloon has a string attached to it. the string is just multiple SKSpriteNode attached with SKPhysicsJointPin with each other. I've inverted gravity so the balloon with attached string got upward and after 3sec timeout it gets smaller. so far it works except for the start attached point of the string is not moved to the correct position of balloon. how to solve this issue?
so i'm adding only the necessary part here otherwise the post gets too bulky. so again see balloon has skaction which resizes the balloon, and how to move the string to correct position while resizing?
Balloon is subclassed SKSpriteNode
Balloon *balloon = [Balloon spriteNodeWithImageNamed:#"balloon.png"];
[balloon setPosition:CGPointMake(200, CGRectGetMinY(scene.frame))];
[balloon setName:#"balloon"];
[balloon setUserInteractionEnabled:NO];
[balloon setPhysicsBody:[SKPhysicsBody bodyWithCircleOfRadius:55]];
balloon.physicsBody.dynamic = YES;
[balloon.physicsBody setRestitution:0.4f];
[balloon.physicsBody setFriction:0.0f];
CGPoint attachPoint = CGPointMake(200, CGRectGetMinY(scene.frame));
//create the rope
SKRopeNode *rope = [SKRopeNode new];
rope.name = #"ropeParent";
[scene addChild:rope];
[rope setAttachmentPoint:attachPoint toNode:balloon];
rope.ropeLength = 6;
[rope runAction:[SKAction sequence:#[[SKAction waitForDuration:4.5], [SKAction removeFromParent]]]];
[balloon runAction:[SKAction sequence:#[[SKAction waitForDuration:4], [SKAction scaleTo:balloon.yScale/2 duration:0.5], [SKAction removeFromParent]]]];
this how i create rope method for creating the length
SKSpriteNode *firstPart = [SKSpriteNode spriteNodeWithImageNamed:#"rope_part.png"];
firstPart.position = _positionOnStartNode;
firstPart.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:firstPart.size];
firstPart.physicsBody.allowsRotation = NO;
for (int i=1; i<ropeLength; i++) {
SKSpriteNode *ropePart = [firstPart copy];
ropePart.position = CGPointMake(firstPart.position.x, firstPart.position.y - (i*ropePart.size.height));
ropePart.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:ropePart.size];
ropePart.physicsBody.allowsRotation = YES;
[self.scene addChild:ropePart];
}
and this is for adding joints for the rope before
SKNode *nodeA = balloon;
SKSpriteNode *nodeB = [_ropeParts objectAtIndex:0];
SKPhysicsJointPin *joint = [SKPhysicsJointPin jointWithBodyA: nodeA.physicsBody
bodyB: nodeB.physicsBody
anchor: _positionOnStartNode];
for (int i=1; i<_ropeParts.count; i++) {
SKSpriteNode *nodeA = [_ropeParts objectAtIndex:i-1];
SKSpriteNode *nodeB = [_ropeParts objectAtIndex:i];
SKPhysicsJointPin *joint = [SKPhysicsJointPin jointWithBodyA: nodeA.physicsBody
bodyB: nodeB.physicsBody
anchor: CGPointMake(CGRectGetMidX(nodeA.frame),
CGRectGetMinY(nodeA.frame))];
[self.scene.physicsWorld addJoint:joint];
}
Related
as the title suggest, i have issue with creating contact between my enemies sprite and the hero laser(bullet). i create my enemies trough the following method and am adding them to the view.
-(void)Enemies{
//not always come
int GoOrNot = [self getRandomNumberBetween:0 to:1];
if(GoOrNot == 1){
SKSpriteNode *enemy;
int randomEnemy = [self getRandomNumberBetween:0 to:1];
if(randomEnemy == 0)
enemy = [SKSpriteNode spriteNodeWithImageNamed:#"enemy_spaceship.png"];
else
enemy = [SKSpriteNode spriteNodeWithImageNamed:#"Spaceship15.png"];
enemy.scale = 0.4;
enemy.position = CGPointMake(450, 0);
enemy.hidden = NO;
CGPoint location = CGPointMake(450, 320);
SKAction *moveAction = [SKAction moveTo:location duration:2.5];
SKAction *doneAction = [SKAction runBlock:(dispatch_block_t)^() {
//NSLog(#"Animation Completed");
enemy.hidden = YES;
}];
SKAction *moveAsteroidActionWithDone = [SKAction sequence:#[moveAction,doneAction ]];
[enemy runAction:moveAsteroidActionWithDone withKey:#"asteroidMoving"];
[self addChild:enemy];
_enemyBullets = [[NSMutableArray alloc] initWithCapacity:kNumEnemyBullet];
for (int i = 0; i < kNumEnemyBullet; ++i) {
SKSpriteNode *enemyBullets = [SKSpriteNode spriteNodeWithImageNamed:#"rocket"];
enemyBullets.hidden = YES;
[enemyBullets setXScale:0.5];
[enemyBullets setYScale:0.5];
[_enemyBullets addObject:enemyBullets];
[enemy addChild:enemyBullets];
}
}
}
then i add the bullets through a mutable array and then adding my bullets to the enemies sprites as their child. that part works. i can create contact between hero and the enemy bullet and it gets detected. what i have issue with is that my hero's laser does not create contact with the enemy thus i can't make the enemy take hit from the laser. i tries adding the physics body to the method i am using but throws all the other sprites into hell and they don't respond properly anymore.
the following code is my collision code which i am using in update method:
for (SKSpriteNode *enemyBullets in _enemyBullets) {
if (enemyBullets.hidden) {
continue;
}
if ([_ship intersectsNode:enemyBullets]) {
enemyBullets.hidden = YES;
SKAction *blink = [SKAction sequence:#[[SKAction fadeOutWithDuration:0.1],
[SKAction fadeInWithDuration:0.1]]];
SKAction *blinkForTime = [SKAction repeatAction:blink count:4];
SKAction *shipExplosionSound = [SKAction playSoundFileNamed:#"explosion_large.caf" waitForCompletion:NO];
[_ship runAction:[SKAction sequence:#[shipExplosionSound,blinkForTime]]];
_lives--;
_livesLabel.text = [NSString stringWithFormat:#"%d Lives", _lives];
NSLog(#"your ship has been hit!");
}
}
is there any way that i can use to create a physics body for my enemies so i can create the contact between the hero laser and the enemies sprite with the same structure i have currently ? any help is amazingly appreciated.
You most certainly can create a physics body for your enemies. Right after this code enemy = [SKSpriteNode spriteNodeWithImageNamed:#"enemy_spaceship.png"]; you can add a physics body like this:
enemy.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:self.size];
enemy.physicsBody.categoryBitMask = CategoryEnemy; // or whatever you need
enemy.physicsBody.collisionBitMask = CategoryRock; // or whatever you need
enemy.physicsBody.contactTestBitMask = CategoryBullet // or whatever you need
enemy.physicsBody.dynamic = NO; // or YES
enemy.physicsBody.allowsRotation = NO; // or YES
enemy.physicsBody.restitution = 0; // or another value between 0 to 1
enemy.physicsBody.friction = 0.0; // or another value between 0 to 1
There are many ways to create a physics body. You can do a rectangle shape, circle shape, outline a texture or draw your own.
You should read the Apple docs on this subject to get a better understanding of what you can do and what properties are available.
I have created two nodes, a projectile node and a target node, each with their respective categories and when they both contact each other, both are removed and depending on the projectile, even more projectiles appear.
The projectiles also are removed when they touch the edge of the screen.
Everything works fine until after a "wave" of targets (I created a method to occasionally spawn 5 targets in a set design) appear and scroll across the screen and projectiles are all over the place contacting more and more targets, now I would understand the node count increasing, but the amount is no where near the amount, the game then lags to the point of the FPS being 2 FPS and the game eventually freezing and the node count stuck to 700.
didBeginContact Method
static inline Enemies *nodeFromBody(SKPhysicsBody *body1, SKPhysicsBody *body2, uint32_t category) {
Enemies *node = nil;
if (body1.categoryBitMask & category) {
node = (Enemies *)body1.node;
}
else if (body2.categoryBitMask & category) {
node = (Enemies *)body2.node;
}
return node;
}
-(void)didBeginContact:(SKPhysicsContact *)contact {
SKPhysicsBody *firstBody, *secondBody;
SKSpriteNode *projectile = nil;
SKSpriteNode *offScreen = nil;
Enemies *target = nil;
firstBody = contact.bodyA;
secondBody = contact.bodyB;
projectile = nodeFromBody(firstBody, secondBody, projectileCategory);
offScreen = nodeFromBody(firstBody, secondBody, offScreenCategory);
target = nodeFromBody(firstBody, secondBody, targetsCategory);
if (projectile && target) {
if ([projectile.name isEqualToString:#"firstShot"]) {
NSLog(#"firstShot");
[projectile removeAllActions];
[projectile removeFromParent];
[ProjectilePatterns pattern1:self spawnPoint:target.position];
[target removeAllActions];
[target removeFromParent];
[Enemies wave1:self spawnPoint:CGPointMake(CGRectGetMidX(self.frame) - 525, CGRectGetMidY(self.frame) - 50)];
}
}
enemyClassMethod
// These are the regular targets, the other method that spawns the wave is essentially creating new enemies and returns them positioned in certain positions.
+(Enemies *)wave1:(SKScene *)scene spawnPoint:(CGPoint)location {
SKAction *delay = [SKAction waitForDuration:5];
SKAction *remove = [SKAction removeFromParent];
SKAction *delayAndRemove = [SKAction sequence:#[delay, remove]];
Enemies *enemy1 = [[Enemies alloc] init];
enemy1 = [Enemies spriteNodeWithColor:[SKColor blackColor] size:CGSizeMake(30, 30)];
enemy1.position = location;
enemy1.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:enemy1.size];
enemy1.physicsBody.categoryBitMask = targetsCategory;
enemy1.physicsBody.contactTestBitMask = projectileCategory;
enemy1.physicsBody.collisionBitMask = 0;
[scene addChild:enemy1];
[enemy1 runAction:delayAndRemove];
[enemy1.physicsBody applyImpulse:CGVectorMake(12, 0)];
return enemy1;
}
Projectile Pattern
+(ProjectilePatterns *)pattern1:(SKScene *)scene spawnPoint:(CGPoint)location {
SKAction *rotate = [SKAction rotateByAngle:1 duration:0.1];
SKAction *rotateForever = [SKAction repeatActionForever:rotate];
ProjectilePatterns *patternBomb = [[ProjectilePatterns alloc] init];
patternBomb = [ProjectilePatterns spriteNodeWithImageNamed:#"contactBomb"];
patternBomb.position = CGPointMake(location.x + 10, location.y);
patternBomb.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:patternBomb.size];
patternBomb.physicsBody.categoryBitMask = projectileCategory;
patternBomb.physicsBody.contactTestBitMask = targetsCategory | offScreenCategory;
patternBomb.physicsBody.collisionBitMask = 0;
patternBomb.physicsBody.friction = 0;
patternBomb.physicsBody.linearDamping = 0;
patternBomb.name = #"p1";
ProjectilePatterns *patternBomb2 = [[ProjectilePatterns alloc] init];
patternBomb2 = [ProjectilePatterns spriteNodeWithImageNamed:#"contactBomb"];
patternBomb2.position = CGPointMake(location.x - 10, location.y);
patternBomb2.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:patternBomb2.size];
patternBomb2.physicsBody.categoryBitMask = projectileCategory;
patternBomb2.physicsBody.contactTestBitMask = targetsCategory | offScreenCategory;
patternBomb2.physicsBody.collisionBitMask = 0;
patternBomb2.physicsBody.friction = 0;
patternBomb2.physicsBody.linearDamping = 0;
patternBomb2.name = #"p1";
[scene addChild:patternBomb];
[patternBomb runAction:rotateForever];
[patternBomb.physicsBody applyImpulse:CGVectorMake(5, 0)];
[scene addChild:patternBomb2];
[patternBomb2 runAction:rotateForever];
[patternBomb2.physicsBody applyImpulse:CGVectorMake(-5, 0)];
return patternBomb;
return patternBomb2;
}
I should also note that the scene's physicsWorld gravity is (0,0). I did this so the impulses movement would be constant.
Right now I have five bricks at the top of the screen all on the same y position and equally spaced apart. I would like to have five more breaks spawn outside of the top of the scene and slide down every 5 seconds. While the new bricks are sliding down I want the previous bricks to slide down to make room for the new. I want this sequence to continue on forever. I would like the new bricks to pick up the same properties of the old ones , such as when a ball hits them the react.
With the code I put in to accomplish this, I get a single brick spawning and then sliding down. Also the new brick does not act the same way as the old, it does not act like its a part of the physics world. How do I get 5 bricks spawning then sliding down and applying the same properties as the other bricks.
This code is the code I added to spawn more bricks:
-(void) spawnMoreBricks:(CGSize)size {
for (int i = 0; i < 5; i++) {
SKSpriteNode *brick = [SKSpriteNode spriteNodeWithImageNamed:#"brick"];
//resize bricks
brick.size = CGSizeMake(60, 30);
//position it
brick.position = CGPointMake(self.size.width/2, self.size.height);
SKAction *wait = [SKAction waitForDuration:5];
SKAction *spawn = [SKAction runBlock:^{[self addChild: brick];
SKAction *move = [SKAction moveByX:0 y:-80 duration:3];
[brick runAction: move];
}];
SKAction *spawnSequence = [SKAction sequence:#[wait, spawn]];
SKAction *repeatSequence = [SKAction repeatActionForever:spawnSequence];
[self runAction:repeatSequence];
}
}
This code adds the bricks into the scene right when it initializes, they react to the ball colliding with them and everything:
- (void) addBricks:(CGSize)size {
for (int i = 0; i < 5; i++) {
//create brick sprite from image
SKSpriteNode *brick = [SKSpriteNode spriteNodeWithImageNamed:#"brick"];
//resize bricks
brick.size = CGSizeMake(60, 30);
//psoition bricks
int xPos = size.width/5 * (i+.5);
int yPos = size.height - 25;
brick.position = CGPointMake(xPos, yPos);
brick.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:brick.frame.size];
brick.physicsBody.dynamic = NO;
brick.physicsBody.categoryBitMask = brickCategory;
//add bricks to scene
[self addChild:brick];
}
}
I'm working on a game that has 3 clouds in the background which are each SKSpriteNodes. In order to create a parallax effect I'm moving them down the screen as the character is moving up (the screen is moving up as well).
I removing them in the update method after they reach the bottom of the screen. I would like to add them back at a Y position 20px above the viewable scene so that would be 500x on an iPhone 4 and 588px on a iPhone 5. Then just repeat over and over.
Then only way I can think of to do this is to chain SKActions and run a sequence, but I don't think that is the best way. I'm trying to find a way to add them back after they have been removed in the update method.
-(id)initWithSize:(CGSize)size {
...
//Moving Clouds
[self performSelector:#selector(createClouds) withObject:nil afterDelay:.2];
}
-(void)createClouds {
SKSpriteNode *cloud1 = [SKSpriteNode spriteNodeWithImageNamed:#"cloud1"];
cloud1.position = CGPointMake(40, 200);
cloud1.xScale = .5;
cloud1.yScale = .5;
cloud1.name = #"Cloud1";
cloud1.zPosition = 0;
SKAction *moveCloud1 = [SKAction moveToY:-20 duration:15];
[cloud1 runAction:[SKAction repeatActionForever:moveCloud1]];
[self addChild:cloud1];
SKSpriteNode *cloud2 = [SKSpriteNode spriteNodeWithImageNamed:#"cloud2"];
cloud2.position = CGPointMake(300, 320);
cloud2.xScale = .5;
cloud2.yScale = .5;
cloud2.name = #"Cloud2";
cloud2.zPosition = 0;
SKAction *moveCloud2 = [SKAction moveToY:-40 duration:15];
[cloud2 runAction:[SKAction repeatActionForever:moveCloud2]];
[self addChild:cloud2];
SKSpriteNode *cloud3 = [SKSpriteNode spriteNodeWithImageNamed:#"cloud3"];
cloud3.position = CGPointMake(200, 450);
cloud3.xScale = .5;
cloud3.yScale = .5;
cloud3.name = #"Cloud3";
cloud3.zPosition = 0;
SKAction *moveCloud3 = [SKAction moveToY:-200 duration:20];
[cloud3 runAction:[SKAction repeatActionForever:moveCloud3]];
[self addChild:cloud3];
}
-(void)update:(CFTimeInterval)currentTime {
....
// Remove Cloud from parent
[self enumerateChildNodesWithName:#"Cloud1" usingBlock:^(SKNode *node, BOOL *stop) {
if (node.position.x < 0 || node.position.y < 0) {
[node removeFromParent];
//Add node back to the scene at a Y position above the screen then move
// the cloud downwards again. Repeat Forever.
// Exp: Move Cloud 1 to X position 40, Y position 500 (20 pixels above the top of the screen for an iPhone 4s)
}
else {
// Do something?
}
}];
You can add an SKAction to move your cloud back to the top:
SKSpriteNode *cloud1 = [SKSpriteNode spriteNodeWithImageNamed:#"cloud1"];
cloud1.position = CGPointMake(40, 200);
cloud1.xScale = .5;
cloud1.yScale = .5;
cloud1.name = #"Cloud1";
cloud1.zPosition = 0;
SKAction *moveCloud1 = [SKAction moveToY:-20 duration:15];
// SKAction to move cloud back to top of screen
SKAction *moveToTop = [SKAction moveToY:CGRectGetHeight(self.frame)+20 duration:0];
SKAction *cloud1Action = [SKAction sequence:#[moveCloud1, moveToTop]];
[cloud1 runAction:[SKAction repeatActionForever:cloud1Action]];
You won't need the code in the update method.
I think you can simply change the position
Also, use CGRectGetMinY to use relative positioning, easier to manage different screen sizes.
And check only the Y position too, because X won't change if they're moving vertically.
This is my idea:
-(void)update:(NSTimeInterval)currentTime {
for(int i = 1; i<=3; i++){
NSString* cloud = [NSString stringWithFormat:#"Cloud%d",i];
[self enumerateChildNodesWithName:cloud usingBlock:^(SKNode *node, BOOL *stop) {
if (node.position.y < 0) {
node.position = CGPointMake(node.position.x,CGRectGetMaxY(self.frame)+20);
}
}];
}
}
in my game I am adding enemies to the scene every second , I need to describe an specific distance between pervious object that my main character move through these enemy , here is my codes that add enemy to the scene :
- (void)createEnemy {
int GoOrNot = [self getRandomNumberBetween:0 to:1];
if(GoOrNot == 1){
int randomEnemy = [self getRandomNumberBetween:0 to:1];
if(randomEnemy == 0)
enemy = [[SKSpriteNode alloc]initWithImageNamed:#"car.png"];
else
enemy = [[SKSpriteNode alloc]initWithImageNamed:#"block.png"];
int xPostion = [self placeRandomObject] ;
int yPostion = 1150;
enemy.position = CGPointMake(xPostion, yPostion);
enemy.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:enemy.size];
enemy.name = #"enemy";
enemy.physicsBody.categoryBitMask = enemyCategory;
enemy.physicsBody.contactTestBitMask = carCategory;
enemy.physicsBody.collisionBitMask = 0;
enemy.physicsBody.dynamic = YES;
enemy.physicsBody.usesPreciseCollisionDetection = YES;
[self addChild:enemy];
SKAction *wait = [SKAction waitForDuration:.20];
SKAction *move = [SKAction moveToY:self.scene.frame.origin.y-10 duration:enemySpeed];
SKAction *remove = [SKAction removeFromParent];
SKAction *runAction = [SKAction sequence:#[wait,move , remove]];
[enemy runAction:[SKAction repeatActionForever:runAction]];
}
}
adding enemy :
- (void)addEnemies {
SKAction *wait = [SKAction waitForDuration:.55];
SKAction *callEnemies = [SKAction runBlock:^{ [self createEnemy];}];
updateEnimies = [SKAction sequence:#[wait,callEnemies]];
[self runAction:[SKAction repeatActionForever:updateEnimies] withKey:#"addEnemy"];
}
You can create new variable to hold the last position of the previous enemy.
CGPoint positionOfLastEnemy;
when you create new enemy assign the position of created enemy to this variable:
positionOfLastEnemy = CGPointMake(xPostion, yPostion);
if you need to update the enemy position you can do it in your collision detection method.
After that just use the positionOfLastEnemy variable to calculate the distance you need.
The other way is to add variable to hold the last enemy
SKSpriteNode *lastEnemy;
in your createEnemy method save reference to your created enemy.
lastEnemy = enemy;
And if you need the distance of the last enemy just use
lastEnemy.position