IOS粒子系统的实现

IOS粒子系统的实现

 IOS的CoreGraphic可以实现简单的粒子系统的效果
我们来简单介绍一下，实现粒子系统其实非常简单，比较复杂的是其参数的设置
实现粒子系统主要用到两个类
CAEmitterLayer和CAEmitterCell 
先介绍一下CAEmitterLayer(发射层)
其主要的属性有

@property(copy) NSArray *emitterCells; //粒子单元数组，有多少个粒子单元@property float birthRate; 出生率因子，每秒产生的粒子数量，默认是1@property float lifetime; 生命周期，单位是秒，默认是1@property CGPoint emitterPosition; 粒子位置默认是CGPointZero@property CGFloat emitterZPosition;  Z轴位置默认是0@property CGSize emitterSize;  发射尺寸@property CGFloat emitterDepth; 发射深度依赖属性emitterShape，可以被忽略 @property(copy) NSString *emitterShape;发射形状kCAEmitterLayerPoint 点 默认值kCAEmitterLayerLine 线kCAEmitterLayerRectangle 三角kCAEmitterLayerCuboid 立方kCAEmitterLayerCircle 圆kCAEmitterLayerSphere 球@property(copy) NSString *emitterMode; 发射模式kCAEmitterLayerPoints 点群kCAEmitterLayerOutline 轮廓kCAEmitterLayerSurface 地面kCAEmitterLayerVolume 团 默认值@property(copy) NSString *renderMode;//渲染模式kCAEmitterLayerUnordered 无序的  默认值kCAEmitterLayerOldestFirst 从头开始kCAEmitterLayerOldestLast 从后面开始kCAEmitterLayerBackToFront 按照z轴kCAEmitterLayerAdditive 加法的@property BOOL preservesDepth; 保留深度，默认为No，如果为true会导致某些属性不确定 @property float velocity; 速度 默认为1@property float scale; 比例，默认为1 @property float spin; 旋转角度@property unsigned int seed; 粒子数量 默认是0CAEmitterCell的 的类的主要属性有 + (id)emitterCell; 构造方法+ (id)defaultValueForKey:(NSString *)key;根据keyPath读取效果- (BOOL)shouldArchiveValueForKey:(NSString *)key; 保存效果@property(copy) NSString *name; 根据keyPath构造@property(getter=isEnabled) BOOL enabled; 能否被渲染@property float birthRate;@property float lifetime, lifetimeRange;   lifetimeRange生命周期范围，默认是0@property CGFloat emissionLatitude, emissionLongitude; 粒子经纬度 默认是0  z轴和x轴的位置@property CGFloat emissionRange; 发射角度，默认是0@property CGFloat velocity, velocityRange;  速度，速度范围@property CGFloat xAcceleration, yAcceleration, zAcceleration; 三方向加速度@property CGFloat scale, scaleRange, scaleSpeed; 缩放，缩放范围，缩放速度@property CGFloat spin, spinRange; 旋转角度 旋转范围@property CGColorRef color; 粒子颜色@property float redRange, greenRange, blueRange, alphaRange; 颜色范围和透明度范围@property float redSpeed, greenSpeed, blueSpeed, alphaSpeed; 速度@property(retain) id contents; 内容 类型是CGImageRef 默认是nil@property CGRect contentsRect; 内容范围 默认是[0,0,1,1]@property(copy) NSString *minificationFilter, *magnificationFilter; 过滤@property float minificationFilterBias;@property(copy) NSArray *emitterCells; 发射的子粒子@property(copy) NSDictionary *style; 继承layer的属性

   

        

     

本人写的Demo
粒子层类 

 

#ifndef IPhone5

    #define IPhone5 ([UIScreen instancesRespondToSelector:@selector(currentMode)] ? CGSizeEqualToSize(CGSizeMake(640, 1136), [[UIScreen mainScreen] currentMode].size) : NO)

#endif

#import <QuartzCore/QuartzCore.h>

typedef enum{    PaticleFromePositionModeNone,    PaticleFromePositionModeTop,    PaticleFromePositionModeCenter,    PaticleFromePositionModeBottom}PaticleFromePositionMode;

@interface PaticleLayer : CAEmitterLayer//发射类型@property(nonatomic,assign) PaticleFromePositionMode fromPositonMode;#pragma 初始化//通过粒子图片名字/数组初始化-(id)initWithImageName:(NSString *)imageName;-(id)initWithImageNameArray:(NSArray*)imageArray;-(id)init;#pragma 粒子图片//发射时间-(void)setEmitterTime:(CGFloat)time;//开始倒计时-(void)begin;@end

#import "PaticleLayer.h"//粒子系统s@interface PaticleLayer(){    //图片数组     __strong NSArray* _imageNameArray;        //发射位置模式    PaticleFromePositionMode _fromPositonMode;        //发射时间    CGFloat _emitterTime;}@end

@implementation PaticleLayer@dynamic fromPositonMode;-(id)init{    self = [super init];    if (self) {        _imageNameArray = [NSMutableArray array];        [self DefaultSetting];    }    return self;}-(id)initWithImageName:(NSString *)imageName{    self = [super init];    if (self) {        _imageNameArray = @[imageName];        [self DefaultSetting];    }    return self;}-(id)initWithImageNameArray:(NSArray *)imageArray{    self = [super init];    if (self) {        _imageNameArray = imageArray;        [self DefaultSetting];    }    return self;}-(void)setFromPositonMode:(PaticleFromePositionMode)fromPositonMode{    switch (fromPositonMode) {        case PaticleFromePositionModeNone:            break;        case PaticleFromePositionModeCenter:            [self setEmitterPosition:CGPointMake(320/2.0f,(480+(IPhone5?88:0))/2)];            break;        case PaticleFromePositionModeTop:            [self setEmitterPosition:CGPointMake(320/2.0f,30)];            break;        case  PaticleFromePositionModeBottom:            [self setEmitterPosition:CGPointMake(320/2.0f,(480+(IPhone5?88:0))-30)];            break;        default:            break;    }    _fromPositonMode = fromPositonMode;}-(PaticleFromePositionMode)fromPositonMode{    return _fromPositonMode;}-(void)setEmitterTime:(CGFloat)time{    _emitterTime = time;}//渐渐消失-(void)fade{    CABasicAnimation* fade = [CABasicAnimation animationWithKeyPath:@"opacity"];    fade.duration = 1.0;    fade.fromValue = @1.0;    fade.toValue = @0.0;    [self addAnimation:fade forKey:@"fade"];    [NSTimer scheduledTimerWithTimeInterval:0.9 target:self selector:@selector(removeFromSuperlayer) userInfo:nil repeats:NO];}//默认设置-(void)DefaultSetting{    //设置出现时间为永远    [self setEmitterTime:-1.0f];        //设置在中间发射    [self setFromPositonMode:PaticleFromePositionModeCenter];    //设置发射尺寸为全屏幕    [self setEmitterSize:CGSizeMake(320*2.0, 0)];    //设置发射模式    [self setEmitterMode:kCAEmitterLayerOutline];    //设置发射形状，默认圆形    [self setEmitterShape:kCAEmitterLayerLine];        //设置阴影透明度    [self setShadowOpacity:1.0];    //设置半径    [self setShadowRadius:0.0];    //    [self setShadowOffset:CGSizeMake(0.0, 1.0)];    //    [self setShadowColor:[[UIColor whiteColor]CGColor]];    //    [self setSeed:arc4random()%30+1];    //跟粒子    CAEmitterCell* rootCell = [CAEmitterCell emitterCell];    [rootCell setBirthRate:5.0];    [rootCell setVelocity:0];    [rootCell setLifetime:0.35];    //Cells    NSArray* children = [self getImageArray];    if (rootCell) {        [rootCell setEmitterCells:children];        [self setEmitterCells:@[rootCell]];    }    else    {        [self setEmitterCells:children];    }}-(CAEmitterCell *)createCellWithImage:(UIImage *)image{    CAEmitterCell *cellLayer = [CAEmitterCell emitterCell];    cellLayer.birthRate= 5.0;    cellLayer.lifetime= 5.0;cellLayer.velocity= -100;// falling down slowlycellLayer.velocityRange = 0;cellLayer.yAcceleration = 2;    cellLayer.emissionRange = 0.5 * M_PI;// some variation in angle    cellLayer.spinRange= 0.25 * M_PI;// slow spin        cellLayer.contents= (id)[image CGImage];    cellLayer.color= [[UIColor colorWithRed:0.600 green:0.658 blue:0.743 alpha:1.000] CGColor];        return cellLayer;}-(NSArray*)getImageArray{    NSMutableArray* array = [NSMutableArray array];    for (NSString* imageName in _imageNameArray) {        UIImage* image = [UIImage imageNamed:imageName];        if (image) {            CAEmitterCell* cell = [self createCellWithImage:image];            [array addObject:cell];        }    }    return array;}-(void)begin{    if (_emitterTime > 0) {        [NSTimer scheduledTimerWithTimeInterval:_emitterTime target:self selector:@selector(fade) userInfo:nil repeats:NO];    }}

 


ViewController

-(IBAction)Render:(id)sender{    PaticleLayer* layer = [[PaticleLayer alloc]initWithImageName:@"birthday.png"];    [layer setEmitterShape:kCAEmitterLayerLine];    [layer setEmitterTime:10.0];    [self.view.layer addSublayer:layer];    [layer begin];}