A simple particle effect implementation in iOS

1. Display

2. Realization of Ideas

1> first to achieve the above effect, the first step to deal with is a simple artboard, on the view with the mouse to slide the time to draw lines, this function can be implemented using Uibezierpath

2> on the implementation of particle effects, you can create a calayer and then copy the layer with Careplicatorlayer to achieve particle effects

3. Code implementation

Encapsulation and writing of Drawview class

////drawview.m//06-Particle effect////Created by Xiaomage on 15/6/24.//Copyright (c) 2015 xiaomage. All rights reserved.//#import "DrawView.h"@interfaceDrawview () @property (nonatomic, strong) Uibezierpath*path; @property (nonatomic, weak) Calayer*Dotlayer, @property (nonatomic, weak) Careplicatorlayer*RepL;@end@implementationDrawview#pragmaMark-Lazy Load point Layer-(Calayer *) dotlayer{if(_dotlayer = =Nil) {        //Create a layerCalayer *layer =[Calayer layer]; CGFloat WH=Ten; Layer.frame= CGRectMake (0, - +, WH, WH); Layer.cornerradius= WH/2; Layer.backgroundcolor=[Uicolor Bluecolor].        Cgcolor;                [_repl Addsublayer:layer]; _dotlayer=layer; }    return_dotlayer;}-(Uibezierpath *) path{if(_path = =Nil) {_path=[Uibezierpath Bezierpath]; }        return_path;}#pragmaMark-Start tapping call-(void) Touchesbegan: (Nsset *) touches withevent: (Uievent *)Event{        //Get Touch ObjectUitouch *touch =[touches anyobject]; //get current Touch pointCgpoint curp =[Touch locationinview:self]; //set the starting point[Self.path movetopoint:curp]; }Static int_instanscount =0;- (void) touchesmoved: (Nsset *) touches withevent: (Uievent *)Event{    //Get Touch ObjectUitouch *touch =[touches anyobject]; //get current Touch pointCgpoint curp =[Touch locationinview:self]; //add a line to a point[_path addlinetopoint:curp]; //Redraw[self setneedsdisplay]; _instanscount++; }//Only override Drawrect:if perform custom drawing.//An empty implementation adversely affects performance during animation.- (void) DrawRect: (cgrect) rect {//Drawing Code[_path stroke];}#pragmaMark-Start Animation-(void) startanim{//Create a frame animationCakeyframeanimation *anim =[cakeyframeanimation animation]; Anim.keypath=@"position"; Anim.path=_path.        Cgpath; Anim.duration=3; Anim.repeatcount=maxfloat;        [Self.dotlayer Addanimation:anim Forkey:nil]; //Note: If the copied sub-layer has animations, first add the animation in the copy//Copy Child layer_repl.instancecount =_instanscount; //Delay Layer Animation_repl.instancedelay =0.2; }#pragmaMark-After loading the xib call, create the replication Layer-(void) awakefromnib{//Creating a replication layerCareplicatorlayer *REPL =[Careplicatorlayer layer]; Repl.frame=Self.bounds;      [Self.layer ADDSUBLAYER:REPL]; _repl=RepL;}#pragmaMark-Redraw-(void) redraw{//Clear Drawing Information_path =Nil;        [Self setneedsdisplay]; //removes the parent control from the layer, and the copy layer is removed. [_dotlayer Removefromsuperlayer]; _dotlayer=Nil; //total number of cleared empty layers_instanscount =0; }@end

Use of Drawview

// Click Start Animation -(Ibaction) Startanim: (ID) sender {        *view = (Drawview *) Self.view;    [View Startanim];    } // Reset button -(ibaction) ReDraw: (ID) sender {        *view = (Drawview *) Self.view;    [View ReDraw];}

A simple particle effect implementation in iOS