sinカーブでくねくねしながら球を周る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 () <SCNSceneRendererDelegate>
@property (nonatomic, weak) SCNView *sceneView;
@property (nonatomic) int count;
@end
struct SCoordinate {
float r;
float t;
float p;
};
typedef struct SCoordinate SCoordinate;
NS_INLINE SCoordinate SCoordinateMake(float x, float y, float z) {
SCoordinate v = {x, y, z};
return v;
}
@interface CustomNode : SCNNode
@property (nonatomic) SCoordinate coordinate;
@property (nonatomic) float baseTheta;
@end
@implementation CustomNode
– (void)setCoordinate:(SCoordinate)coordinate {
_coordinate = coordinate;
float x = coordinate.r * sin(coordinate.t) * cos(coordinate.p);
float y = coordinate.r * sin(coordinate.t) * sin(coordinate.p);
float z = coordinate.r * cos(coordinate.t);
self.position = SCNVector3Make(x, y, z);
}
@end
@implementation ViewController
– (void)viewDidLoad {
[super viewDidLoad];
[self setupScene];
[self createSphere];
[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;
sv.delegate = self;
[self.view addSubview:sv];
self.sceneView = sv;
}
– (void)createSphere {
SCNSphere *sp = [SCNSphere sphereWithRadius:20];
sp.firstMaterial.diffuse.contents = [[self color:1] colorWithAlphaComponent:0.8];
SCNNode *spn = [SCNNode nodeWithGeometry:sp];
[self.sceneView.scene.rootNode addChildNode:spn];
for (int i=0; i<4; i++) {
SCNSphere *s = [SCNSphere sphereWithRadius:1];
s.firstMaterial.diffuse.contents = [self color:i + 1];
s.firstMaterial.shininess = 1.0;
CustomNode *sNode = [CustomNode node];
sNode.baseTheta = (M_PI / 6.0) * (i+1);
sNode.geometry = s;
sNode.name = [NSString stringWithFormat:@”satellite”];
sNode.coordinate = SCoordinateMake(20,sNode.baseTheta,1);
[self.sceneView.scene.rootNode addChildNode:sNode];
}
}
– (void)createCamera {
SCNNode *camera = [SCNNode node];
camera.camera = [SCNCamera camera];
camera.position = SCNVector3Make(0, 0, 80);
[self.sceneView.scene.rootNode addChildNode:camera];
}
– (void)renderer:(id<SCNSceneRenderer>)aRenderer updateAtTime:(NSTimeInterval)time {
[[self.sceneView.scene.rootNode.childNodes filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@”name = %@”, @”satellite”]] enumerateObjectsUsingBlock:^(CustomNode *cn, NSUInteger idx, BOOL *stop) {
float phi = self.count * M_PI / 50.0;
cn.coordinate = SCoordinateMake(20, cn.baseTheta + 0.1 * sin(4 * phi), phi);
}];
self.count = (self.count + 1) % 100;
[aRenderer setPlaying:YES];
}
#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[] = {0x202A38, 0x5E606F, 0x0E606F, 0xD1DBBD, 0xF5FFCC};
return ColorHex(colorCode[i]);
}
@end