粒子动画

粒子动画中的关键概念是CAEmitterLayer和 CAEmitterCell,其中CAEmitterLayer是发射源,CAEmitterCell是发射出去的粒子.

其余的一些属性官网或者百度都可以知道.

另附代码如下

    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(self.view.bounds.size.width / 2 ,                                                            self.view.bounds.size.height, 200, 200)];    view.backgroundColor = [UIColor redColor];    view.layer.cornerRadius = 50;    [self.view addSubview:view];    //create particle emmitter layer    //CAEmitterLayer负责发射粒子(粒子也可以发射粒子)    CAEmitterLayer *emitter = [CAEmitterLayer layer];    emitter.frame = view.bounds;    //决定粒子发射形状的中心点    emitter.emitterPosition = CGPointMake(100, 100);    emitter.emitterZPosition = 3.0;    emitter.emitterShape = kCAEmitterLayerPoints;//发射器形状    emitter.emitterMode = kCAEmitterLayerPoints;//3d圆形的体积内发射    emitter.PReservesDepth = YES; //是否开启三维空间模式    emitter.emitterDepth = 2.0;//发射器的深度，有时可能会产生立体效果    emitter.spin = 5;//粒子的旋转角度    [view.layer addSublayer:emitter];    emitter.renderMode = kCAEmitterLayerAdditive;//渲染模式    //emitter.emitterPosition = CGPointMake(emitter.frame.size.width /2.0, emitter.frame.size.height / 2.0);    //creat a particle template]    CAEmitterCell *cell = [[CAEmitterCell alloc] init];    cell.contents = (__bridge id _Nullable)([UIImage imageNamed:@"d00"].CGImage);    cell.birthRate = 15.0;    cell.lifetime = 5.0;    cell.enabled = YES;//是否打开粒子的渲染效果    //  cell.color = [UIColor colorWithRed:1 green:0.5 blue:0.1 alpha:1.0].CGColor;    cell.alphaspeed = -0.4;    cell.velocity = 50; //粒子的速度    cell.velocityRange = 70;//粒子的速度范围    cell.emissionRange = M_PI * 2.0;    //creat a particle template]    CAEmitterCell *cell2 = [[CAEmitterCell alloc] init];    cell2.contents = (__bridge id _Nullable)([UIImage imageNamed:@"d01"].CGImage);    cell2.birthRate = 15.0;    cell2.lifetime = 5.0;    cell2.color = [UIColor colorWithRed:1 green:0.5 blue:0.1 alpha:1.0].CGColor;    cell2.alphaSpeed = -0.4;    cell2.velocity = 50;    cell2.velocityRange = 50;    cell2.emissionRange = M_PI * 2.0;    //add pareticle template to emitter    emitter.emitterCells = @[cell,cell2];