My ground node is not appearing.

Question

There is nothing there, and I'm can't find what I'm missing. Can someone tell me what I've missed?

from groundNode.m:

#import "GroundNode.h"
#import "Util.h"

@implementation GroundNode

+ (instancetype) groundWithSize:(CGSize)size {
    GroundNode *ground = [self spriteNodeWithColor:[SKColor greenColor] size:size];
    ground.name = @"ground";
    ground.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:size];
    ground.position = CGPointMake(size.width/2, size.height/2);

    return ground;
}

From GamePlayScene.m:

GroundNode *ground = [GroundNode groundWithSize:CGSizeMake(self.frame.size.width, 22)];
    [self addChild:ground];

Answer 1 · 2015-01-19T04:57:41Z

January 19, 2015 4:57am

try adding this into your GroundNode.M implementation class: try messing around with the value changing from 1, to 15 etc.. it seems to be hiding the green box behind the background by default.

hope this helps.

      ground.zPosition = 1;

Answer 2 · 2014-12-19T21:05:06Z

December 19, 2014 9:05pm

are you sure its not just dropping off the screen because of gravity? what do you have gravity set to in your physics world?

try commenting out the line that sets the gravity force and see if the ground node stays put. that way you can see if its actually being added to the scene correctly

Answer 3 · 2014-12-19T21:06:08Z

December 19, 2014 9:06pm

I'm not sure. Here is what I have for physicsWorld:

 self.physicsWorld.gravity = CGVectorMake(0, -9.8);
 self.physicsWorld.contactDelegate = self;

Answer 4 · 2014-12-19T21:10:21Z

December 19, 2014 9:10pm

Thanks Stone. although, no change.

Answer 5 · 2014-12-19T21:20:59Z

December 19, 2014 9:20pm

Definitely

//
//  GamePlayScene.m
//  Space Cat
//
//  Created by Jared Watkins on 12/16/14.
//  Copyright (c) 2014 Jared Watkins. All rights reserved.
//

#import "GamePlayScene.h"
#import "MachineNode.h"
#import "SpaceCatNode.h"
#import "ProjectileNode.h"
#import "SpaceDogNode.h"
#import "GroundNode.h"
#import "Util.h"

@interface GamePlayScene ()

@property (nonatomic) NSTimeInterval lastUpdateTimeInterval;
@property (nonatomic) NSTimeInterval timeSinceEnemyAdded;
@property (nonatomic) NSTimeInterval totalGameTime;
@property (nonatomic) NSInteger minSpeed;
@property (nonatomic) NSTimeInterval addEnemyTimeInterval;
//  SFX
@property (nonatomic) SKAction *damageSFX;
@property (nonatomic) SKAction *explodeSFX;
@property (nonatomic) SKAction *laserSFX;

@end

@implementation GamePlayScene

-(void)didMoveToView:(SKView *)view {

    self.lastUpdateTimeInterval = 0;
    self.timeSinceEnemyAdded = 0;
    self.addEnemyTimeInterval = 1.5;
    self.totalGameTime = 0;
    self.minSpeed = SpaceDogMinSpeed;

    /* Setup your scene here */
    SKSpriteNode *background = [SKSpriteNode spriteNodeWithImageNamed:@"background_1"];
    background.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
    background.xScale = 1.18;
    background.yScale = 1.18;
    [self addChild:background];

    MachineNode *machine = [MachineNode machineAtPosition:CGPointMake(CGRectGetMidX(self.frame), 12) ];
    [self addChild:machine];

    SpaceCatNode *spaceCat = [SpaceCatNode spaceCatAtPosition:CGPointMake(machine.position.x, machine.position.y-2)];
    [self addChild:spaceCat];



//    Add Physics to the scene (World)
    self.physicsWorld.gravity = CGVectorMake(0, -9.8);
    self.physicsWorld.contactDelegate = self;

    GroundNode *ground = [GroundNode groundWithSize:CGSizeMake(self.frame.size.width, 22)];
    [self addChild:ground];

    [self setupSounds];

}

//  SFX
- (void) setupSounds {
    self.damageSFX = [SKAction playSoundFileNamed:@"Damage.caf" waitForCompletion:NO];
    self.explodeSFX = [SKAction playSoundFileNamed:@"Explode.caf" waitForCompletion:NO];
    self.laserSFX = [SKAction playSoundFileNamed:@"Laser.caf" waitForCompletion:NO];
}

- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    for (UITouch *touch in touches) {
        CGPoint position = [touch locationInNode:self];
        [self shootProjectileTowardsPosition:position];
    }

}

- (void) shootProjectileTowardsPosition:(CGPoint)position {
    SpaceCatNode *spaceCat = (SpaceCatNode*)[self childNodeWithName:@"SpaceCat"];
    [spaceCat performTap];

    MachineNode *machine = (MachineNode *)[self childNodeWithName:@"machine"];


    ProjectileNode *projectile = [ProjectileNode projectileAtPosition:CGPointMake(machine.position.x, machine.position.y + machine.frame.size.height - 15)];
    [self addChild:projectile];
    [projectile moveTowardsPosition:position];
//    SFX - Laser
    [self runAction:self.laserSFX];

}

//  place enemies
- (void) addSpaceDog {

    NSUInteger randomSpaceDog = [Util randomWithMin:0 max:2];

    //    randomly place spaceDogs
    SpaceDogNode *spaceDog = [SpaceDogNode spaceDogOfType:randomSpaceDog];

    //    vary the velocity between -100 and -50 as found in Util.h
    float dy = [Util randomWithMin:SpaceDogMinSpeed max:spaceDogMaxSpeed];
    spaceDog.physicsBody.velocity = CGVectorMake(0, dy);

    //    keep the spaceDogs within the bounds of the frame
    float y = self.frame.size.height + spaceDog.size.height;  // right above the height of the frame
    float x = [Util randomWithMin:10 + spaceDog.size.width max:self.frame.size.width - spaceDog.size.width - 10]; // between the left edge and right edge of the screen. left side (min) has 10 point margin.

    spaceDog.position = CGPointMake(x, y);
    [self addChild:spaceDog];

//    Hared Coded add 2 spaceDogs

//    SpaceDogNode *spaceDogA = [SpaceDogNode spaceDogOfType:SpaceDodTypeA];
//    spaceDogA.position = CGPointMake(100, 300);
//    [self addChild:spaceDogA];
//    
//    SpaceDogNode *spaceDogB = [SpaceDogNode spaceDogOfType:SpaceDogTypeB];
//    spaceDogB.position = CGPointMake(200, 300);
//    [self addChild:spaceDogB];
}

//  add spaceDogs depending on how many seconds have passed since the last spaceDog was added
- (void) update:(NSTimeInterval)currentTime {
    if ( self.lastUpdateTimeInterval) {
        self.timeSinceEnemyAdded += currentTime - self.lastUpdateTimeInterval;
        self.totalGameTime += currentTime - self.lastUpdateTimeInterval;
    }
    //  add a space dog if one hasn't been added in the last addEnemyTimeInterval in seconds
    if (self.timeSinceEnemyAdded > self.addEnemyTimeInterval ) {
        [self addSpaceDog];
        self.timeSinceEnemyAdded = 0;
    }
    //    set the last update to the current time
    self.lastUpdateTimeInterval = currentTime;

//    Increase the difficulty over time
    //    if 480 second or 8 minutes have passed
    if (self.totalGameTime > 480) {
        self.addEnemyTimeInterval = 0.50;
        self.minSpeed = -160;
        //        4 minutes
    } else if ( self.totalGameTime > 240 ) {
        self.addEnemyTimeInterval = 0.65;
        self.minSpeed = -150;
        //        2 minutes
    } else if ( self.totalGameTime > 20 ) {
        self.addEnemyTimeInterval = .75;
        self.minSpeed = -125;
        //        30 seconds
    } else if ( self.totalGameTime > 10 ) {
        self.addEnemyTimeInterval = 1.00;
        self.minSpeed = -100;
    }

}

- (void) didBeginContact:(SKPhysicsContact *)contact {

        SKPhysicsBody *firstBody, *secondBody;

//    check which categoryBitMask is bigger by comparing enemy = 0010 to projectile 0000
    if ( contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask ) {
        firstBody = contact.bodyA;
        secondBody = contact.bodyB;
    } else {
        firstBody = contact.bodyA;
        secondBody = contact.bodyB;
    }


    if ( firstBody.categoryBitMask == collisionCategoryEnemy && secondBody.categoryBitMask == collisionCategoryProjectile ) {
        NSLog(@"BAM!");

        SpaceDogNode *spaceDog = (SpaceDogNode *)firstBody.node;
        ProjectileNode *projectile = (ProjectileNode *)secondBody.node;

//        SFX - Explode
        [self runAction:self.explodeSFX];

//      if the projectile and spaceDog collide, remove them from the scene
        [spaceDog removeFromParent];
        [projectile removeFromParent];


    } else if (firstBody.categoryBitMask == collisionCategoryEnemy && secondBody.categoryBitMask == collisionCategoryGround ) {
        NSLog(@"Hit Ground");

//        SFX - Damage
        [self runAction:self.damageSFX];

        //        remove spaceDog if it hits the ground
        SpaceDogNode *spaceDog = (SpaceDogNode *)firstBody.node;
        [spaceDog removeFromParent];

    }

    [self createDebrisAtPosition:contact.contactPoint];

}

//  debris
- (void) createDebrisAtPosition:(CGPoint)position {
    NSInteger numberOfPieces = [Util randomWithMin:5 max:20];


    for (int i=0; i < numberOfPieces; i++) {
        NSInteger randomPiece = [Util randomWithMin:1 max:4];
        NSString *imageName = [NSString stringWithFormat:@"debri_%d",randomPiece];

        SKSpriteNode *debris = [SKSpriteNode spriteNodeWithImageNamed:imageName];
        debris.position = position;
        [self addChild:debris];

        debris.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:debris.frame.size];
        debris.physicsBody.categoryBitMask = collisionCategoryDebris;
        debris.physicsBody.contactTestBitMask = 0;
        debris.physicsBody.collisionBitMask = collisionCategoryGround | collisionCategoryDebris;
        debris.name = @"debris";

        //     scatter debris on explosion contact
        debris.physicsBody.velocity = CGVectorMake([Util randomWithMin:-150 max:150],
                                                   [Util randomWithMin:150 max:350]);

        [debris runAction:[SKAction waitForDuration:2.0] completion:^{
            [debris removeFromParent];
        }];

    }
}

//-(void) update:(NSTimeInterval)currentTime {
//    
//    NSLog(@"%f",fmod(currentTime, 60));
//}



@end

And here is the full groundNode.m. I commented out the bodyWithRectangleOfSize line and have setupPhysicsBody, but even when I comment out setupPhysicsBody, and uncomment bodyWithRectangleOfSize, The ground still does not appear.

//
//  GroundNode.m
//  Space Cat
//
//  Created by Jared Watkins on 12/17/14.
//  Copyright (c) 2014 Jared Watkins. All rights reserved.
//

#import "GroundNode.h"
#import "Util.h"

@implementation GroundNode

+ (instancetype) groundWithSize:(CGSize)size {
    GroundNode *ground = [self spriteNodeWithColor:[SKColor greenColor] size:size];
    ground.name = @"ground";
//    ground.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:size];
    ground.position = CGPointMake(size.width/2, size.height/2);
    [ground setupPhysicsBody];

    return ground;
}

- (void) setupPhysicsBody {
    self.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:self.frame.size];
    self.physicsBody.affectedByGravity = NO;
    self.physicsBody.dynamic = NO;
//    collisions
    self.physicsBody.categoryBitMask = collisionCategoryGround;
    self.physicsBody.collisionBitMask = collisionCategoryDebris;
    self.physicsBody.contactTestBitMask = collisionCategoryEnemy;

}

@end

Answer 6 · 2014-12-19T21:51:34Z

December 19, 2014 9:51pm

ok, I see that the ground is mid screen because of the exploding debris, but it still doesn't appear.

Here's a screen shot: Imgur

The bigger problem is that the spaceDogs pass through the ground. it's like there are 5 space dogs stacked and only the top one is destroyed. the same thing happens with the projectiles when they contact the spaceDogs. Also the NSLog(@"Hit Ground"); does not get triggered or show up in the console. and the SFX for enemy hitting the ground is not triggered.

I won't be able to count lives for when the spaceDogs hit the ground.

An ideas?

Answer 7 · 2014-12-19T22:00:38Z

December 19, 2014 10:00pm

I have it like this:

+ (instancetype) groundWithSize:(CGSize)size {
    GroundNode *ground = [self spriteNodeWithColor:[SKColor greenColor] size:size];
    ground.name = @"ground";
//    ground.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:size];
    ground.position = CGPointMake(size.width/2, size.height/2);
    [ground setupPhysicsBody];

    return ground;
}

Answer 8 · 2014-12-19T22:10:16Z

December 19, 2014 10:10pm

ok, It's not appearing, and I can't tell an change.

Screenshot Imgur

//
//  GroundNode.m
//  Space Cat
//
//  Created by Jared Watkins on 12/17/14.
//  Copyright (c) 2014 Jared Watkins. All rights reserved.
//

#import "GroundNode.h"
#import "Util.h"

@implementation GroundNode

+ (instancetype) groundWithSize:(CGSize)size {
    GroundNode *ground = [self spriteNodeWithColor:[SKColor greenColor] size:size];
    ground.name = @"ground";
    ground.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:size];
    ground.position = CGPointMake(size.width/2, size.height/2);
    [ground setupPhysicsBody];

    return ground;
}

- (void) setupPhysicsBody {
    self.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:self.frame.size];
    self.physicsBody.affectedByGravity = NO;
    self.physicsBody.dynamic = NO;
//    collisions
    self.physicsBody.categoryBitMask = collisionCategoryGround;
    self.physicsBody.collisionBitMask = collisionCategoryDebris;
    self.physicsBody.contactTestBitMask = collisionCategoryEnemy;

}

@end

Answer 9 · 2014-12-19T22:12:54Z

December 19, 2014 10:12pm

Well, I'm glad it's not just me. Thanks for your help, nonetheless.

Answer 10 · 2014-12-19T22:23:36Z

December 19, 2014 10:23pm

sure

groundNode.h

//
//  GroundNode.h
//  Space Cat
//
//  Created by Jared Watkins on 12/17/14.
//  Copyright (c) 2014 Jared Watkins. All rights reserved.
//

#import <SpriteKit/SpriteKit.h>

@interface GroundNode : SKSpriteNode

+ (instancetype) groundWithSize:(CGSize)size;

@end

Answer 11 · 2014-12-19T22:26:40Z

December 19, 2014 10:26pm

I think there is a problem in GamePlayScene.m because The NSLog(@"Hit Ground"); is not being logged in the console. However, NSLog(@"BAM!"); is being logged.

- (void) didBeginContact:(SKPhysicsContact *)contact {

        SKPhysicsBody *firstBody, *secondBody;

//    check which categoryBitMask is bigger by comparing enemy = 0010 to projectile 0000
    if ( contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask ) {
        firstBody = contact.bodyA;
        secondBody = contact.bodyB;
    } else {
        firstBody = contact.bodyA;
        secondBody = contact.bodyB;
    }


    if ( firstBody.categoryBitMask == collisionCategoryEnemy && secondBody.categoryBitMask == collisionCategoryProjectile ) {
        NSLog(@"BAM!");

        SpaceDogNode *spaceDog = (SpaceDogNode *)firstBody.node;
        ProjectileNode *projectile = (ProjectileNode *)secondBody.node;

//        SFX - Explode
        [self runAction:self.explodeSFX];

//      if the projectile and spaceDog collide, remove them from the scene
        [spaceDog removeFromParent];
        [projectile removeFromParent];


    } else if (firstBody.categoryBitMask == collisionCategoryEnemy && secondBody.categoryBitMask == collisionCategoryGround ) {
        NSLog(@"Hit Ground");

//        SFX - Damage
        [self runAction:self.damageSFX];

        //        remove spaceDog if it hits the ground
        SpaceDogNode *spaceDog = (SpaceDogNode *)firstBody.node;
        [spaceDog removeFromParent];

    }

    [self createDebrisAtPosition:contact.contactPoint];

}

Answer 12 · 2014-12-28T21:01:38Z

December 28, 2014 9:01pm

I haven't gotten to the collision stuff in this app yet but I had the same ground not appearing thing and the only way i made it appear was that I set the zPosition property to 1.0. I'm not sure how this would impact the collision detection (you probably have to make all the dogNodes on zPosition 1.0 as well

Answer 13 · 2015-01-02T20:58:16Z

January 2, 2015 8:58pm

i have same problem !! any one can help us ?

Answer 14 · 2015-01-02T20:59:55Z

January 2, 2015 8:59pm

The problem because of BackGround try to comment

 SKSpriteNode * background =[SKSpriteNode spriteNodeWithImageNamed:@"background_1"];
    background.position=CGPointMake(self.size.width/2, self.size.height/2);
        [self addChild:background];

and look what happen

Answer 15 · 2015-07-06T20:12:47Z

July 6, 2015 8:12pm

I had the same issue and tweaked the zPosition for both background and ground, as Brittany Stubbs suggested though I had to use the opposite settings... on THGamePlayScene.m I set background.zPosition = 1;

and then I set ground.zPosition = 15;

Good luck!

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