繋げた板をくるくるまわすiPhoneアプリのサンプルコードを描いてみます。
#import “ViewController.h”
@import SceneKit;
@interface ViewController ()
@property (nonatomic, weak) SCNView *sceneView;
@end
@implementation ViewController
– (void)viewDidLoad {
[super viewDidLoad];
[self setupScene];
SCNNode *main = [self createWheel:40 x:0];
SCNPhysicsHingeJoint *joint = [SCNPhysicsHingeJoint jointWithBody:main.physicsBody axis:SCNVector3Make(0, 0, 1) anchor:SCNVector3Zero];
[self.sceneView.scene.physicsWorld addBehavior:joint];
[self createCamera];
}
– (void)setupScene {
SCNView *sv = [[SCNView alloc] initWithFrame:self.view.bounds];
sv.backgroundColor = [self color:0];
sv.scene = [SCNScene scene];
sv.autoenablesDefaultLighting = YES;
sv.allowsCameraControl = YES;
[self.view addSubview:sv];
self.sceneView = sv;
}
– (SCNNode *)createWheel:(float)l x:(float)x{
SCNBox *bar = [SCNBox boxWithWidth:l*0.95 height:0.2 length:2 chamferRadius:0];
bar.firstMaterial.diffuse.contents = [UIColor colorWithHue:l*0.02 saturation:1 brightness:1 alpha:1];//[self color:1];
SCNNode *barNode = [SCNNode nodeWithGeometry:bar];
barNode.position = SCNVector3Make(x, 0, 0);
barNode.physicsBody = [SCNPhysicsBody dynamicBody];
barNode.physicsBody.collisionBitMask = 0x0;
[self.sceneView.scene.rootNode addChildNode:barNode];
if (l > 4) {
SCNNode *right = [self createWheel:l * 0.5 x:x + l*0.25];
SCNNode *left = [self createWheel:l * 0.5 x:x -l*0.25];
for (SCNNode *child in @[right, left]) {
SCNPhysicsHingeJoint *joint = [SCNPhysicsHingeJoint jointWithBodyA:child.physicsBody axisA:SCNVector3Make(0, 0, 1) anchorA:SCNVector3Zero bodyB:barNode.physicsBody axisB:SCNVector3Make(0, 0, 1) anchorB:[self.sceneView.scene.rootNode convertPosition:child.position toNode:barNode]];
[self.sceneView.scene.physicsWorld addBehavior:joint];
}
} else {
barNode.physicsBody.collisionBitMask = 0xF;
}
return barNode;
}
– (void)createCamera {
SCNNode *camera = [SCNNode node];
camera.camera = [SCNCamera camera];
camera.position = SCNVector3Make(35, 0, 60);
camera.rotation = SCNVector4Make(0, 1, 0.1, 0.5);
[self.sceneView.scene.rootNode addChildNode:camera];
}
– (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
SCNBox *box = [SCNBox boxWithWidth:1 height:1 length:1 chamferRadius:0];
box.firstMaterial.diffuse.contents = [self color:3];
SCNNode *boxNode = [SCNNode nodeWithGeometry:box];
int rand = arc4random() % 40;
boxNode.position = SCNVector3Make(rand – 20,10,0);
boxNode.physicsBody = [SCNPhysicsBody dynamicBody];
[self.sceneView.scene.rootNode addChildNode:boxNode];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[boxNode removeFromParentNode];
});
}
#define ColorHex(rgb) [UIColor colorWithRed:((rgb & 0xFF0000)>>16)/255.0 green:((rgb & 0xFF00)>>8)/255.0 blue:(rgb & 0xFF)/255.0 alpha:1.0]
– (UIColor *)color:(int)i {
if (i>4) return nil;
int colorCode[] = {0x006D8D, 0x008A6E, 0x549E39, 0x8AB833, 0xC0CF3A};
return ColorHex(colorCode[i]);
}
@end