problem with Chipmunk cpBodyApplyImpulse rotation

roko · 10-13-2010, 04:30 AM

Hi all. I have some trouble when i call:

Code:

cpBodeApplyImpulse(cpBody *body, cpVect j, cpVect r)

My problem is that a ball is spinning after i call cpBodeApplyImpulse. How can i change it behavior such that the ball wouldn't spin at all?

here is code of creating of the ball:

Code:

ballSprite = [CCSprite spriteWithFile:@"ball.png"];
		[_tileMap addChild:ballSprite z:2];
		//[self addChild:ballSprite z:3];
		ballSprite.position = cpv(x,y);
		cpBody *someBody = cpBodyNew(10, 10);
		someBody->p = ccp(x, y);
		cpSpaceAddBody(space, someBody);
		player = cpCircleShapeNew(someBody, 10, cpvzero);
		player->e = 0.5f;
		player->u = 0.5f;
		player->data = ballSprite;
		cpSpaceAddShape(space, player);

here is code where i call cpBodeApplyImpulse:

Code:

- (void) ccTouchesBegan: (NSSet *)touches withEvent: (UIEvent *)event
{
	UITouch *touch = [touches anyObject];
	CGPoint pos = [touch locationInView:nil];
	pos = [[CCDirector sharedDirector] convertToGL:pos];	
	if (pos.y>upRect.origin.y && pos.y<upRect.origin.y + 55) {
		CGPoint playerPos = [(CCSprite *)(player->data) position];
		playerPos = [[CCDirector sharedDirector] convertToGL:playerPos];
			cpBodyApplyImpulse(player->body, CGPointMake(playerPos.x, playerPos.y), CGPointMake(playerPos.x, playerPos.y+1000));
		}
}

If need i can attach the rest of my code.

kqe · 11-08-2010, 07:36 AM

Use

Code:

cpBody *someBody = cpBodyNew(10, INFINITY);

to create your body.

Quote:

Originally Posted by roko

Hi all. I have some trouble when i call:

Code:

cpBodeApplyImpulse(cpBody *body, cpVect j, cpVect r)

My problem is that a ball is spinning after i call cpBodeApplyImpulse. How can i change it behavior such that the ball wouldn't spin at all?

here is code of creating of the ball:

Code:

ballSprite = [CCSprite spriteWithFile:@"ball.png"];
		[_tileMap addChild:ballSprite z:2];
		//[self addChild:ballSprite z:3];
		ballSprite.position = cpv(x,y);
		cpBody *someBody = cpBodyNew(10, 10);
		someBody->p = ccp(x, y);
		cpSpaceAddBody(space, someBody);
		player = cpCircleShapeNew(someBody, 10, cpvzero);
		player->e = 0.5f;
		player->u = 0.5f;
		player->data = ballSprite;
		cpSpaceAddShape(space, player);

here is code where i call cpBodeApplyImpulse:

Code:

- (void) ccTouchesBegan: (NSSet *)touches withEvent: (UIEvent *)event
{
	UITouch *touch = [touches anyObject];
	CGPoint pos = [touch locationInView:nil];
	pos = [[CCDirector sharedDirector] convertToGL:pos];	
	if (pos.y>upRect.origin.y && pos.y<upRect.origin.y + 55) {
		CGPoint playerPos = [(CCSprite *)(player->data) position];
		playerPos = [[CCDirector sharedDirector] convertToGL:playerPos];
			cpBodyApplyImpulse(player->body, CGPointMake(playerPos.x, playerPos.y), CGPointMake(playerPos.x, playerPos.y+1000));
		}
}

If need i can attach the rest of my code.

roko · 11-26-2010, 09:02 AM

kqe, i have sorted it out but anyway thanks you a lot for advance.