2 different filtered shapes think they are the same

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2 different filtered shapes think they are the same

(8 posts) (5 voices)

Started 11 months ago by jonn4y
Latest reply from zzt4

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jonn4y
Member

Hi, i have been pulling my hair out over this code for about a week now, i have 3 different kinds of eggs, normal, bad eggs, golden eggs normal egg will give you 1 points, bad egg will -1 point and golden egg will +10 points.
when a bad egg is collected it does -1 but when either a golden egg or a normal egg is collected it gives +11, and putting CCLogs in the contact listeners shows both the if statments for normal and golden are being called and i just cant figure it out, i have re-wrote it, renamed things, changed things but no joy.

im hoping one of you guys will look at this and say "what a n00b, you put abc when it should be xyz, go read this bla bla"
that would be very helpful.

here is my scene:

Defining the bits

#define kCategoryGround 0x01
#define kCategoryPaddle 0x02
#define kCategoryNorm 0x04
#define kCategorySmell 0x08
#define kCategoryGolden 0x16
#define kCategoryPegs 0x32

create a paddle:

// Create paddle and add it to the layer
        CCSprite *paddle = [CCSprite spriteWithFile:@"goal.png"];
        paddle.position = ccp(screenSize.width/2, 50);
        paddle.tag = 2;
        [self addChild:paddle];

        // Create paddle body
        b2BodyDef paddleBodyDef;
        paddleBodyDef.type = b2_dynamicBody;
        paddleBodyDef.position.Set(screenSize.width/2/PTM_RATIO, 50/PTM_RATIO);
        paddleBodyDef.userData = paddle;
        _paddleBody = world->CreateBody(&paddleBodyDef);

        // Create paddle shape
        b2PolygonShape paddleShape;
        paddleShape.SetAsBox(paddle.contentSize.width/PTM_RATIO/3,
                             paddle.contentSize.height/PTM_RATIO/3);

        // Create shape definition and add to body
        b2FixtureDef paddleShapeDef;
        paddleShapeDef.shape = &paddleShape;
        paddleShapeDef.density = 10.0f;
        paddleShapeDef.friction = 0.4f;
        paddleShapeDef.restitution = 0.1f;
        paddleShapeDef.filter.groupIndex = 2; //int16(-3);
        paddleShapeDef.filter.categoryBits = kCategoryPaddle; //uint16(65535);
        paddleShapeDef.filter.maskBits = kCategoryGolden | kCategoryNorm | kCategorySmell | kCategoryGround ;
        _paddleFixture = _paddleBody->CreateFixture(&paddleShapeDef);

        // Restrict paddle along the x axis
        b2PrismaticJointDef jointDef;
        b2Vec2 worldAxis(1.0f, 0.0f);
        jointDef.collideConnected = true;
        jointDef.Initialize(_paddleBody, groundBody, _paddleBody->GetWorldCenter(), worldAxis);
        world->CreateJoint(&jointDef);

Create my eggs:

#pragma mark Normal Eggs
-(void) tick2: (ccTime) dt
{
 //   CGSize screenSize = [[CCDirector sharedDirector] winSize];

    CCSprite *Egg = [CCSprite spriteWithFile:@"ball.png" rect:CGRectMake(0, 0, 25, 25)];
	Egg.position = ccp(160, 420);
	Egg.tag = 1;
	[self addChild:Egg];

	// Create ball body
	b2BodyDef ballBodyDef;
	ballBodyDef.type = b2_dynamicBody;
	ballBodyDef.position.Set(160/PTM_RATIO, 420/PTM_RATIO);
	ballBodyDef.userData = Egg;
	ballBody = world->CreateBody(&ballBodyDef);
    ballBodyDef.angularDamping = 0.9f;

	// Create circle shape
	b2CircleShape circle;
	float radiusInMeters = (Egg.contentSize.width / PTM_RATIO) * 0.5f;
    circle.m_radius = radiusInMeters;

	// Create shape definition and add to body
	b2FixtureDef ballShapeDef;
	ballShapeDef.shape = &circle;
	ballShapeDef.density = 5.0f;
	ballShapeDef.friction = 10.f;
	ballShapeDef.restitution = 0.1f;
    ballShapeDef.filter.groupIndex = -3; //int16(-3);
    ballShapeDef.filter.categoryBits = kCategoryNorm; //uint16(65535);
    ballShapeDef.filter.maskBits = kCategoryGround| kCategoryPaddle;

	_ballFixture = ballBody->CreateFixture(&ballShapeDef);

    int fromNumber = -6;
    int toNumber = 10;
    daForce = (arc4random()%(toNumber-fromNumber))+fromNumber;

   // NSLog(@"its %i", daForce);

    b2Vec2 force = b2Vec2(daForce, 5);
    ballBody->ApplyLinearImpulse(force, ballBodyDef.position);

}

#pragma mark Bad Eggs
-(void) tickSmell: (ccTime) dt
{
    //   CGSize screenSize = [[CCDirector sharedDirector] winSize];

    int fromNo = 0;
    int toNo = 10;
    smell = (arc4random()%(toNo-fromNo))+fromNo;

   // NSLog(@"its %i", daForce);

    if (smell == 5) {

    CCSprite *Smelly = [CCSprite spriteWithFile:@"graphicEggRotten.png" rect:CGRectMake(0, 0, 25, 25)];
	Smelly.position = ccp(160, 420);
	Smelly.tag = 1;
	[self addChild:Smelly];

	// Create ball body
	b2BodyDef badEggBodyDef;
	badEggBodyDef.type = b2_dynamicBody;
	badEggBodyDef.position.Set(160/PTM_RATIO, 420/PTM_RATIO);
	badEggBodyDef.userData = Smelly;
	badEggBody = world->CreateBody(&badEggBodyDef);
    badEggBodyDef.angularDamping = 0.9f;

	// Create circle shape
	b2CircleShape circle;
	float radiusInMeters = (Smelly.contentSize.width / PTM_RATIO) * 0.5f;
    circle.m_radius = radiusInMeters;

	// Create shape definition and add to body
	b2FixtureDef badEggShapeDef;
	badEggShapeDef.shape = &circle;
	badEggShapeDef.density = 5.0f;
	badEggShapeDef.friction = 10.f;
	badEggShapeDef.restitution = 0.1f;
    badEggShapeDef.filter.groupIndex = -3; //int16(-3);
    badEggShapeDef.filter.categoryBits = kCategorySmell; //uint16(65535);
    badEggShapeDef.filter.maskBits =   kCategoryGround | kCategoryPaddle;

	_badEggFixture = badEggBody->CreateFixture(&badEggShapeDef);

    int fromNumber = -6;
    int toNumber = 10;
    daForce = (arc4random()%(toNumber-fromNumber))+fromNumber;

    NSLog(@"its %i", daForce);

    b2Vec2 force = b2Vec2(daForce, 5);
    badEggBody->ApplyLinearImpulse(force, badEggBodyDef.position);
    }

}

#pragma mark Gold Eggs
-(void) tickGold: (ccTime) dt
{
    //   CGSize screenSize = [[CCDirector sharedDirector] winSize];

    int fromNo = 0;
    int toNo = 10;
    gold = (arc4random()%(toNo-fromNo))+fromNo;

    // NSLog(@"its %i", daForce);

    if (gold == 5) {

        CCSprite *Goldy = [CCSprite spriteWithFile:@"graphicEggGolden.png" rect:CGRectMake(0, 0, 25, 25)];
        Goldy.position = ccp(160, 420);
        Goldy.tag = 1;
        [self addChild:Goldy];

        // Create Golden Egg body
        b2BodyDef goldEggBodyDef;
        goldEggBodyDef.type = b2_dynamicBody;
        goldEggBodyDef.position.Set(160/PTM_RATIO, 420/PTM_RATIO);
        goldEggBodyDef.userData = Goldy;
        goldEggBody = world->CreateBody(&goldEggBodyDef);
        goldEggBodyDef.angularDamping = 0.9f;

        // Create circle shape
        b2CircleShape circle;
        float radiusInMeters = (Goldy.contentSize.width / PTM_RATIO) * 0.5f;
        circle.m_radius = radiusInMeters;

        // Create shape definition and add to body
        b2FixtureDef goldEggShapeDef;
        goldEggShapeDef.shape = &circle;
        goldEggShapeDef.density = 5.0f;
        goldEggShapeDef.friction = 10.f;
        goldEggShapeDef.restitution = 0.1f;
        goldEggShapeDef.filter.groupIndex = -3; //int16(-3);
        goldEggShapeDef.filter.categoryBits = kCategoryGolden; //uint16(65535);
        goldEggShapeDef.filter.maskBits =  kCategoryGround | kCategoryPaddle;

        _goldEggFixture = goldEggBody->CreateFixture(&goldEggShapeDef);

        int fromNumber = -6;
        int toNumber = 10;
        daForce = (arc4random()%(toNumber-fromNumber))+fromNumber;

        NSLog(@"its %i", daForce);

        b2Vec2 force = b2Vec2(daForce, 5);
        goldEggBody->ApplyLinearImpulse(force, goldEggBodyDef.position);

    }

}

my collision detection / contact listener:

std::vector<b2Body *>toDestroy;
    std::vector<MyContact>::iterator pos;
    for(pos = _contactListener->_contacts.begin(); pos != _contactListener->_contacts.end(); ++pos) {
        MyContact contact = *pos;

        if ((contact.fixtureA->GetFilterData().categoryBits & kCategoryNorm &&
             contact.fixtureB->GetFilterData().categoryBits & kCategoryPaddle) ||
            (contact.fixtureB->GetFilterData().categoryBits & kCategoryNorm &&
             contact.fixtureA->GetFilterData().categoryBits & kCategoryPaddle)) {
                NSLog(@"Normal Egg Caught");
                //increase the score by 1
                score = score + 1;
                [scoreLabel setString: [NSString stringWithFormat:@"%d",score]];
            }

        if ((contact.fixtureA->GetFilterData().categoryBits & kCategoryGolden &&
             contact.fixtureB->GetFilterData().categoryBits & kCategoryPaddle) ||
            (contact.fixtureB->GetFilterData().categoryBits & kCategoryGolden &&
             contact.fixtureA->GetFilterData().categoryBits & kCategoryPaddle)) {

                NSLog(@"Golden Egg Caught");
                //increase the score by 10
                score = score + 9;
                [scoreLabel setString: [NSString stringWithFormat:@"%d",score]];

                NSString* playedTenSeconds = @"ID_Golden_Egg";
                GameKitHelper* gkHelper = [GameKitHelper sharedGameKitHelper];
                GKAchievement* achievement = [gkHelper getAchievementByID:playedTenSeconds];
                if (achievement.completed == NO)
                {
                    float percent = achievement.percentComplete + 100;
                    [gkHelper reportAchievementWithID:playedTenSeconds percentComplete:percent];
                }

            }

      if ((contact.fixtureA->GetFilterData().categoryBits & kCategorySmell &&
             contact.fixtureB->GetFilterData().categoryBits & kCategoryPaddle) ||
            (contact.fixtureB->GetFilterData().categoryBits & kCategorySmell &&
             contact.fixtureA->GetFilterData().categoryBits & kCategoryPaddle)) {

                NSLog(@"Bad Egg Caught");
                //decrease the score by 1
                score = score - 1;
                [scoreLabel setString: [NSString stringWithFormat:@"%d",score]];

                NSString* badegg = @"ID_Bad_Egg";
                GameKitHelper* gkHelper = [GameKitHelper sharedGameKitHelper];
                GKAchievement* achievement = [gkHelper getAchievementByID:badegg];
                if (achievement.completed == NO)
                {
                    float percent = achievement.percentComplete + 100;
                    [gkHelper reportAchievementWithID:badegg percentComplete:percent];
                }

            }

        b2Body *bodyA = contact.fixtureA->GetBody();
        b2Body *bodyB = contact.fixtureB->GetBody();

        if (bodyA->GetUserData() != NULL && bodyB->GetUserData() != NULL) {
            CCSprite *spriteA = (CCSprite *) bodyA->GetUserData();
            CCSprite *spriteB = (CCSprite *) bodyB->GetUserData();

            // Sprite A = ball, Sprite B = Block
            if (spriteA.tag == 1 && spriteB.tag == 2) {
                if (std::find(toDestroy.begin(), toDestroy.end(), bodyA) == toDestroy.end()) {
                    toDestroy.push_back(bodyA);
                }
            }
            // Sprite B = Ball, Sprite A = Block
             if (spriteA.tag == 2 && spriteB.tag == 1) {
                if (std::find(toDestroy.begin(), toDestroy.end(), bodyB) == toDestroy.end()) {
                    toDestroy.push_back(bodyB);
                }
            }
        }
    }

    std::vector<b2Body *>::iterator pos2;
    for(pos2 = toDestroy.begin(); pos2 != toDestroy.end(); ++pos2) {
        b2Body *body = *pos2;
        if (body->GetUserData() != NULL) {
            CCSprite *sprite = (CCSprite *) body->GetUserData();
            [self removeChild:sprite cleanup:YES];
        }
      //  NSLog(@"destroying body");
        world->DestroyBody(body);
        CCLOG(@"1 <- ballbody was Deleted!");

    }

Please help me figure this out, ANY help is appreciated.

Regards
Jonn4y

Posted 11 months ago #

aeroplane
Member

Well, I'm not sure what the problem is, but maybe if you re-tagged your eggs so each type was a different tag number and then did your collision detection based on the tag number, it might help pinpoint the issue. If it works after that, then you know there is a filtering problem, if it doesn't then it's something else.

Posted 11 months ago #
Birkemose
Moderator
Wow, thats a LOT of code for adding 10 if the egg is golden!

I managed to read your defines in the top ( phew ), and it looks like bit coding.
If that is the case,
```
#define kCategoryGolden 0x16
#define kCategoryPegs 0x32
```
should be
```
#define kCategoryGolden 0x10
#define kCategoryPegs 0x20
```
Posted 11 months ago #
Studder
Member

What's the advantage in doing it in bit code rather doing it like 1,2,3,4?

Posted 11 months ago #
jonn4y
Member

@Birkemose

YOU ARE A LEGEND!

every example i looked at for bit coding only ever went upto 8 so i assumed it would just follow on going X2, i changed them to 0x10 and 0x20 and it worked a dream..

and i know the coding isnt very good yet, wanted to get the functions right before i start cleaning it all up.

but thanks again you have just solved a problem i have had for a week in a matter of minutes

:)
cheers
jonn4y

Posted 11 months ago #
Birkemose
Moderator
Bit coding is a convenient way of storing a lot of boolean information in the least possible space. A 64 bit int can potentially store 64 bools, could be 64 levels completed or not.

While this memory-wise not is important today, it also forces you to use good solid typing, and that is always important.

If bit 0 in player status means player has shield on, you would never write
```
if ( player.status & 0x01 ) ...
```
because you would not know yourself what it ment after 30 seconds.
You would write
```
#define PLAYER_HAS_SHIELDS_ON 0x01

if ( player.status & PLAYER_HAS_SHIELDS_ON ) ...
```
Now your typing is good, and you will never get in doubt.

In any case, it is a matter of "taste" wether you would do it this way, or create a BOOL playerHasShieldsOn.
Hardware works this way, so I guess former hardware guys ( like myself ) like this approach.

EDIT:
Cool Jonn4y :)
Posted 11 months ago #
jonn4y
Member

thanks for that, you just explained there what i couldnt understand in the tutorials, i knew what i was typing i just didnt know why

Posted 11 months ago #
zzt4
Member
For collision categories, I would even recommend using bitshifting to get the proper values for your categories. So your categories would then look like this:
```
#define kCategoryGround  0x01 << 0
#define kCategoryPaddle  0x01 << 1
#define kCategoryNorm    0x01 << 2
#define kCategorySmell   0x01 << 3
#define kCategoryGolden  0x01 << 4
#define kCategoryPegs    0x01 << 5
```
In my opinion it's a little easier to read and less error prone. (Especially if you're going to use all 64 bits hehehe).
Posted 11 months ago #

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