能产生粒子效果的CAEmitterLayer
能产生粒子效果的CAEmitterLayer
下雪效果:
// // RootViewController.m // Cell // // Copyright (c) 2014年 Y.X. All rights reserved. // #import "RootViewController.h" @interface RootViewController () @end @implementation RootViewController - (void)viewDidLoad { [super viewDidLoad]; self.view.backgroundColor = [UIColor blackColor]; // 创建粒子Layer CAEmitterLayer *snowEmitter = [CAEmitterLayer layer]; // 粒子发射位置 snowEmitter.emitterPosition = CGPointMake(120,20); // 发射源的尺寸大小 snowEmitter.emitterSize = self.view.bounds.size; // 发射模式 snowEmitter.emitterMode = kCAEmitterLayerSurface; // 发射源的形状 snowEmitter.emitterShape = kCAEmitterLayerLine; // 创建雪花类型的粒子 CAEmitterCell *snowflake = [CAEmitterCell emitterCell]; // 粒子的名字 snowflake.name = @"snow"; // 粒子参数的速度乘数因子 snowflake.birthRate = 1.0; snowflake.lifetime = 120.0; // 粒子速度 snowflake.velocity =10.0; // 粒子的速度范围 snowflake.velocityRange = 10; // 粒子y方向的加速度分量 snowflake.yAcceleration = 2; // 周围发射角度 snowflake.emissionRange = 0.5 * M_PI; // 子旋转角度范围 snowflake.spinRange = 0.25 * M_PI; snowflake.contents = (id)[[UIImage imageNamed:@"snow"] CGImage]; // 设置雪花形状的粒子的颜色 snowflake.color = [[UIColor whiteColor] CGColor]; snowflake.scaleRange = 0.6f; snowflake.scale = 0.7f; snowEmitter.shadowOpacity = 1.0; snowEmitter.shadowRadius = 0.0; snowEmitter.shadowOffset = CGSizeMake(0.0, 0.0); // 粒子边缘的颜色 snowEmitter.shadowColor = [[UIColor whiteColor] CGColor]; // 添加粒子 snowEmitter.emitterCells = @[snowflake]; // 将粒子Layer添加进图层中 [self.view.layer addSublayer:snowEmitter]; } @end
烟花效果:
// // RootViewController.m // Cell // // Copyright (c) 2014年 Y.X. All rights reserved. // #import "RootViewController.h" @interface RootViewController () @end @implementation RootViewController - (void)viewDidLoad { [super viewDidLoad]; self.view.backgroundColor = [UIColor blackColor]; // Cells spawn in the bottom, moving up CAEmitterLayer *fireworksEmitter = [CAEmitterLayer layer]; CGRect viewBounds = self.view.layer.bounds; fireworksEmitter.emitterPosition = \ CGPointMake(viewBounds.size.width/2.0, viewBounds.size.height); fireworksEmitter.emitterSize = CGSizeMake(viewBounds.size.width/2.0, 0.0); fireworksEmitter.emitterMode = kCAEmitterLayerOutline; fireworksEmitter.emitterShape = kCAEmitterLayerLine; fireworksEmitter.renderMode = kCAEmitterLayerAdditive; fireworksEmitter.seed = (arc4random()%100)+1; // Create the rocket CAEmitterCell* rocket = [CAEmitterCell emitterCell]; rocket.birthRate = 1.0; rocket.emissionRange = 0.25 * M_PI; // some variation in angle rocket.velocity = 380; rocket.velocityRange = 100; rocket.yAcceleration = 75; rocket.lifetime = 1.02; // we cannot set the birthrate < 1.0 for the burst rocket.contents = (id) [[UIImage imageNamed:@"DazRing"] CGImage]; rocket.scale = 0.2; rocket.color = [[UIColor redColor] CGColor]; rocket.greenRange = 1.0; // different colors rocket.redRange = 1.0; rocket.blueRange = 1.0; rocket.spinRange = M_PI; // slow spin // the burst object cannot be seen, but will spawn the sparks // we change the color here, since the sparks inherit its value CAEmitterCell* burst = [CAEmitterCell emitterCell]; burst.birthRate = 1.0; // at the end of travel burst.velocity = 0; burst.scale = 2.5; burst.redSpeed =-1.5; // shifting burst.blueSpeed =+1.5; // shifting burst.greenSpeed =+1.0; // shifting burst.lifetime = 0.35; // and finally, the sparks CAEmitterCell* spark = [CAEmitterCell emitterCell]; spark.birthRate = 400; spark.velocity = 125; spark.emissionRange = 2* M_PI; // 360 deg spark.yAcceleration = 75; // gravity spark.lifetime = 3; spark.contents = (id) [[UIImage imageNamed:@"snow"] CGImage]; spark.scaleSpeed =-0.2; spark.greenSpeed =-0.1; spark.redSpeed = 0.4; spark.blueSpeed =-0.1; spark.alphaSpeed =-0.25; spark.spin = 2* M_PI; spark.spinRange = 2* M_PI; // putting it together fireworksEmitter.emitterCells = [NSArray arrayWithObject:rocket]; rocket.emitterCells = [NSArray arrayWithObject:burst]; burst.emitterCells = [NSArray arrayWithObject:spark]; [self.view.layer addSublayer:fireworksEmitter]; } @end
/* The birth rate of each cell is multiplied by this number to give the
* actual number of particles created every second. Default value is one.
* Animatable. */
@property float birthRate;
/* The cell lifetime range is multiplied by this value when particles are
* created. Defaults to one. Animatable. */
@property float lifetime;
/* The center of the emission shape. Defaults to (0, 0, 0). Animatable. */
@property CGPoint emitterPosition;
@property CGFloat emitterZPosition;
/* The size of the emission shape. Defaults to (0, 0, 0). Animatable.
* Depending on the `emitterShape' property some of the values may be
* ignored. */
@property CGSize emitterSize;
@property CGFloat emitterDepth;
/* Multiplies the cell-defined particle velocity. Defaults to one.
* Animatable. */
@property float velocity;
/* Multiplies the cell-defined particle scale. Defaults to one. Animatable. */
@property float scale;
/* Multiplies the cell-defined particle spin. Defaults to one. Animatable. */
@property float spin;
你需要知道的非常重要的细节:
CAEmitterCell的动画属性挺多的,但有点奇葩的是,必须是通过KVC设置值才行的通,而且,动画结束时的值也必须通过KVC设置才有效......
// // RootViewController.m // Cell // // Copyright (c) 2014年 Y.X. All rights reserved. // #import "RootViewController.h" #import "YXGCD.h" @interface RootViewController () @end @implementation RootViewController - (void)viewDidLoad { [super viewDidLoad]; self.view.backgroundColor = [UIColor blackColor]; // 创建粒子Layer CAEmitterLayer *snowEmitter = [CAEmitterLayer layer]; // 粒子发射位置 snowEmitter.emitterPosition = CGPointMake(120,20); // 发射源的尺寸大小 snowEmitter.emitterSize = self.view.bounds.size; // 发射模式 snowEmitter.emitterMode = kCAEmitterLayerSurface; // 发射源的形状 snowEmitter.emitterShape = kCAEmitterLayerLine; // 创建雪花类型的粒子 CAEmitterCell *snowflake = [CAEmitterCell emitterCell]; // 粒子参数的速度乘数因子 snowflake.birthRate = 20.0; snowflake.lifetime = 120.0; // 粒子速度 snowflake.velocity =10.0; // 粒子的速度范围 snowflake.velocityRange = 10; // 粒子y方向的加速度分量 snowflake.yAcceleration = 200; // 周围发射角度 snowflake.emissionRange = 0.5 * M_PI; // 子旋转角度范围 snowflake.spinRange = 0.25 * M_PI; snowflake.contents = (id)[[UIImage imageNamed:@"snow"] CGImage]; // 设置雪花形状的粒子的颜色 snowflake.color = [[UIColor whiteColor] CGColor]; snowEmitter.shadowOpacity = 1.0; snowEmitter.shadowRadius = 0.0; snowEmitter.shadowOffset = CGSizeMake(0.0, 0.0); // 粒子边缘的颜色 snowEmitter.shadowColor = [[UIColor whiteColor] CGColor]; // 粒子的名字 snowflake.name = @"snow"; // 添加粒子 snowEmitter.emitterCells = @[snowflake]; // 将粒子Layer添加进图层中 [self.view.layer addSublayer:snowEmitter]; // 7秒后执行 [[GCDQueue mainQueue] execute:^{ // 设置基本动画 CABasicAnimation *ani = \ [CABasicAnimation animationWithKeyPath:@"emitterCells.snow.birthRate"]; ani.fromValue = @(20.0); ani.toValue = @(0.0); ani.duration = 12.f; // 设置结束时的值 [snowEmitter setValue:[NSNumber numberWithFloat:0] forKeyPath:@"emitterCells.snow.birthRate"]; // 添加动画 [snowEmitter addAnimation:ani forKey:nil]; } afterDelay:NSEC_PER_SEC * 7]; } @end
