-(void)renderViewInSpace:(UIView*)view atPos:(cpVect)atPos withRotAngleInRadians:(cpFloat)withRotAngleInRadians
{
     view.transform = CGAffineTransformIdentity;
     //translate to the center of the main view. this is the first step to simulate the chipmunk coordinate system
     view.transform = CGAffineTransformTranslate(view.transform, self.view.bounds.size.width/2.0, self.view.bounds.size.height/2.0);
     //tanslate to position, inversing the y-coordinate
     view.transform = CGAffineTransformTranslate(view.transform, atPos.x, -atPos.y);
     //translate the y position so that we render at top-left and not center
     view.transform = CGAffineTransformTranslate(view.transform, -view.bounds.size.width/2, -view.bounds.size.height/2);
     //rotate, but since we inversed the y-axis, inverse the rotation
     view.transform = CGAffineTransformRotate(view.transform, -withRotAngleInRadians);
}

#import "ObjectiveChipmunk.h"

#define GRABABLE_MASK_BIT (1<<31)
#define NOT_GRABABLE_MASK (~GRABABLE_MASK_BIT)

@interface BounceViewController : UIViewController
{
    NSMutableArray *shapes;
    UIView *boxView;

    ChipmunkSpace *space;
    ChipmunkBody *box;
    double timeStep;
}

-(void)setupSpace;
-(void)update;
-(void)renderViewInSpace:(UIView*)view atPos:(cpVect)atPos withRotAngleInRadians:(cpFloat)withRotAngleInRadians;

@end

#import "BounceViewController.h"

@implementation BounceViewController

- (void)dealloc
{
    [box release];
    [space release];
    [shapes release];
    [boxView release];

    [super dealloc];
}

- (void)viewDidLoad
{
    cpInitChipmunk();

    [self setupSpace];
    [NSTimer scheduledTimerWithTimeInterval:1.0/60.0 target:self selector:@selector(update) userInfo:nil repeats:YES];

    [super viewDidLoad];
}

-(void)update
{
    cpBodyUpdatePosition(box.body, timeStep);
    [space step:timeStep];

    [self renderViewInSpace:boxView atPos:box.pos withRotAngleInRadians:box.angle];

    for(int i=0; i<shapes.count; i++)
    {
        ChipmunkSegmentShape *shape = [shapes objectAtIndex:i];
        UIImageView* imageView = (UIImageView*)shape.data;
        [self renderViewInSpace:imageView atPos:shape.body.pos withRotAngleInRadians:shape.body.angle];
    }
}

-(void)renderViewInSpace:(UIView*)view atPos:(cpVect)atPos withRotAngleInRadians:(cpFloat)withRotAngleInRadians
{
    view.transform = CGAffineTransformIdentity;
    //translate to the center of the main view. this is the first step to simulate the chipmunk coordinate system
    view.transform = CGAffineTransformTranslate(view.transform, self.view.bounds.size.width/2.0, self.view.bounds.size.height/2.0);
    //tanslate to position, inversing the y-coordinate
    view.transform = CGAffineTransformTranslate(view.transform, atPos.x, -atPos.y);
    //translate the y position so that we render at top-left and not center
    view.transform = CGAffineTransformTranslate(view.transform, -view.bounds.size.width/2, -view.bounds.size.height/2);
    //rotate, but since we inversed the y-axis, inverse the rotation
    view.transform = CGAffineTransformRotate(view.transform, -withRotAngleInRadians);
}

-(void)setupSpace
{
    timeStep = 1.0/60.0;

    space = [[ChipmunkSpace alloc] init];
    space.gravity = cpv(0.0, -600.0);

    ChipmunkBody *body;
    ChipmunkShape *shape;

    box = [[ChipmunkBody alloc] initStaticBody];
    box.angVel = 0.4;

    boxView = [[UIView alloc] init];

    // Set up the static box.
    cpFloat boxWidth = 600.0;
    cpFloat boxHeight = 600.0;

    cpVect a = cpv(-boxWidth/2, -boxHeight/2);
    cpVect b = cpv(-boxWidth/2,  boxHeight/2);
    cpVect c = cpv( boxWidth/2,  boxHeight/2);
    cpVect d = cpv( boxWidth/2, -boxHeight/2);

    shape = [space add:[ChipmunkSegmentShape segmentWithBody:box from:a to:b radius:0.0]];
    shape.elasticity = 1.0; shape.friction = 1.0;
    shape.layers = NOT_GRABABLE_MASK;

    shape = [space add:[ChipmunkSegmentShape segmentWithBody:box from:b to:c radius:0.0]];
    shape.elasticity = 1.0; shape.friction = 1.0;
    shape.layers = NOT_GRABABLE_MASK;

    shape = [space add:[ChipmunkSegmentShape segmentWithBody:box from:c to:d radius:0.0]];
    shape.elasticity = 1.0; shape.friction = 1.0;
    shape.layers = NOT_GRABABLE_MASK;

    shape = [space add:[ChipmunkSegmentShape segmentWithBody:box from:d to:a radius:0.0]];
    shape.elasticity = 1.0; shape.friction = 1.0;
    shape.layers = NOT_GRABABLE_MASK;

    boxView.frame = CGRectMake(0, 0, boxWidth, boxHeight);

    boxView.backgroundColor = [UIColor blueColor];
    [self.view addSubview:boxView];

    if(shapes == NULL)
    {
        shapes = [[NSMutableArray alloc] init];
    }

    // Add the bricks.
    for(int i=0; i<3; i++)
    {
        for(int j=0; j<7; j++)
        {
            cpFloat width = 200.0/4;
            cpFloat height = 340.0/4;

            body = [space add:[ChipmunkBody bodyWithMass:1.0 andMoment:cpMomentForBox(1.0, width, height)]];
            body.pos = cpv( (boxWidth/2)-(i*width)-(width/2), (boxHeight/2)-(j*height)-(height/2));
            shape = [space add:[ChipmunkPolyShape boxWithBody:body width:width height:height]];
            shape.elasticity = 0.0; shape.friction = 1.0;

            UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Cozmo.png"]];
            imageView.contentMode = UIViewContentModeScaleAspectFill;
            imageView.clipsToBounds = TRUE;
            imageView.frame = CGRectMake(0, 0, width, height);
            [self.view addSubview:imageView];
            shape.data = imageView;
            [shapes addObject:shape];
        }
    }
}

// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return YES;
}

- (void)didReceiveMemoryWarning
{
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload
{
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}

@end