Android实现粒子爆炸效果的方法
本文实例讲述了Android实现粒子爆炸效果的方法。分享给大家供大家参考。具体如下：
1.Explosion.java文件：
packagenet.obviam.particles.model;
importandroid.graphics.Canvas;
importandroid.graphics.Rect;
importandroid.util.Log;
publicclassExplosion{
privatestaticfinalStringTAG=Explosion.class.getSimpleName();
publicstaticfinalintSTATE_ALIVE=0;
//atleast1particleisalive
publicstaticfinalintSTATE_DEAD=1;
//allparticlesaredead
privateParticle[]particles;
//particlesintheexplosion
privateintx,y;
//theexplosion'sorigin
privatefloatgravity;
//thegravityoftheexplosion(+upward,-down)
privatefloatwind;
//speedofwindonhorizontal
privateintsize;//numberofparticles
privateintstate;//whetherit'sstillactiveornot
publicExplosion(intparticleNr,intx,inty){
Log.d(TAG,"Explosioncreatedat"+x+","+y);
this.state=STATE_ALIVE;
this.particles=newParticle[particleNr];
for(inti=0;i<this.particles.length;i++){
Particlep=newParticle(x,y);
this.particles[i]=p;
}
this.size=particleNr;
}
publicParticle[]getParticles(){
returnparticles;
}
publicvoidsetParticles(Particle[]particles){
this.particles=particles;
}
publicintgetX(){
returnx;
}
publicvoidsetX(intx){
this.x=x;
}
publicintgetY(){
returny;
}
publicvoidsetY(inty){
this.y=y;
}
publicfloatgetGravity(){
returngravity;
}
publicvoidsetGravity(floatgravity){
this.gravity=gravity;
}
publicfloatgetWind(){
returnwind;
}
publicvoidsetWind(floatwind){
this.wind=wind;
}
publicintgetSize(){
returnsize;
}
publicvoidsetSize(intsize){
this.size=size;
}
publicintgetState(){
returnstate;
}
publicvoidsetState(intstate){
this.state=state;
}
//helpermethods-------------------------
publicbooleanisAlive(){
returnthis.state==STATE_ALIVE;
}
publicbooleanisDead(){
returnthis.state==STATE_DEAD;
}
publicvoidupdate(){
if(this.state!=STATE_DEAD){
booleanisDead=true;
for(inti=0;i<this.particles.length;i++){
if(this.particles[i].isAlive()){
this.particles[i].update();
isDead=false;
}
}
if(isDead)
this.state=STATE_DEAD;
}
}
publicvoidupdate(Rectcontainer){
if(this.state!=STATE_DEAD){
booleanisDead=true;
for(inti=0;i<this.particles.length;i++){
if(this.particles[i].isAlive()){
this.particles[i].update(container);
//this.particles[i].update();
isDead=false;
}
}
if(isDead)
this.state=STATE_DEAD;
}
}
publicvoiddraw(Canvascanvas){
for(inti=0;i<this.particles.length;i++){
if(this.particles[i].isAlive()){
this.particles[i].draw(canvas);
}
}
}
}
2.Particle.java文件如下：
packagenet.obviam.particles.model;
importandroid.graphics.Canvas;
importandroid.graphics.Color;
importandroid.graphics.Paint;
importandroid.graphics.Rect;
publicclassParticle{
publicstaticfinalintSTATE_ALIVE=0;//particleisalive
publicstaticfinalintSTATE_DEAD=1;//particleisdead
publicstaticfinalintDEFAULT_LIFETIME=200;//playwiththis
publicstaticfinalintMAX_DIMENSION=5;//themaximumwidthorheight
publicstaticfinalintMAX_SPEED=10;//maximumspeed(perupdate)
privateintstate;//particleisaliveordead
privatefloatwidht;//widthoftheparticle
privatefloatheight;//heightoftheparticle
privatefloatx,y;//horizontalandverticalposition
privatedoublexv,yv;//verticalandhorizontalvelocity
privateintage;//currentageoftheparticle
privateintlifetime;//particledieswhenitreachesthisvalue
privateintcolor;//thecoloroftheparticle
privatePaintpaint;//internalusetoavoidinstantiation
publicintgetState(){
returnstate;
}
publicvoidsetState(intstate){
this.state=state;
}
publicfloatgetWidht(){
returnwidht;
}
publicvoidsetWidht(floatwidht){
this.widht=widht;
}
publicfloatgetHeight(){
returnheight;
}
publicvoidsetHeight(floatheight){
this.height=height;
}
publicfloatgetX(){
returnx;
}
publicvoidsetX(floatx){
this.x=x;
}
publicfloatgetY(){
returny;
}
publicvoidsetY(floaty){
this.y=y;
}
publicdoublegetXv(){
returnxv;
}
publicvoidsetXv(doublexv){
this.xv=xv;
}
publicdoublegetYv(){
returnyv;
}
publicvoidsetYv(doubleyv){
this.yv=yv;
}
publicintgetAge(){
returnage;
}
publicvoidsetAge(intage){
this.age=age;
}
publicintgetLifetime(){
returnlifetime;
}
publicvoidsetLifetime(intlifetime){
this.lifetime=lifetime;
}
publicintgetColor(){
returncolor;
}
publicvoidsetColor(intcolor){
this.color=color;
}
//helpermethods-------------------------
publicbooleanisAlive(){
returnthis.state==STATE_ALIVE;
}
publicbooleanisDead(){
returnthis.state==STATE_DEAD;
}
publicParticle(intx,inty){
this.x=x;
this.y=y;
this.state=Particle.STATE_ALIVE;
this.widht=rndInt(1,MAX_DIMENSION);
this.height=this.widht;
//this.height=rnd(1,MAX_DIMENSION);
this.lifetime=DEFAULT_LIFETIME;
this.age=0;
this.xv=(rndDbl(0,MAX_SPEED*2)-MAX_SPEED);
this.yv=(rndDbl(0,MAX_SPEED*2)-MAX_SPEED);
//smoothingoutthediagonalspeed
if(xv*xv+yv*yv>MAX_SPEED*MAX_SPEED){
xv*=0.7;
yv*=0.7;
}
this.color=Color.argb(255,rndInt(0,255),rndInt(0,255),rndInt(0,255));
this.paint=newPaint(this.color);
}
/**
*Resetstheparticle
*@paramx
*@paramy
*/
publicvoidreset(floatx,floaty){
this.state=Particle.STATE_ALIVE;
this.x=x;
this.y=y;
this.age=0;
}
//Returnanintegerthatrangesfrommininclusivetomaxinclusive.
staticintrndInt(intmin,intmax){
return(int)(min+Math.random()*(max-min+1));
}
staticdoublerndDbl(doublemin,doublemax){
returnmin+(max-min)*Math.random();
}
publicvoidupdate(){
if(this.state!=STATE_DEAD){
this.x+=this.xv;
this.y+=this.yv;
//extractalpha
inta=this.color>>>24;
a-=2;//fadeby5
if(a<=0){//ifreachedtransparencykilltheparticle
this.state=STATE_DEAD;
}else{
this.color=(this.color&0x00ffffff)+(a<<24);//setthenewalpha
this.paint.setAlpha(a);
this.age++;//increasetheageoftheparticle
//this.widht*=1.05;
//this.height*=1.05;
}
if(this.age>=this.lifetime){//reachedtheendifitslife
this.state=STATE_DEAD;
}
//http://lab.polygonal.de/2007/05/10/bitwise-gems-fast-integer-math/
//32bit
//varcolor:uint=0xff336699;
//vara:uint=color>>>24;
//varr:uint=color>>>16&0xFF;
//varg:uint=color>>>8&0xFF;
//varb:uint=color&0xFF;
}
}
publicvoidupdate(Rectcontainer){
//updatewithcollision
if(this.isAlive()){
if(this.x<=container.left||this.x>=container.right-this.widht){
this.xv*=-1;
}
//Bottomis480andtopis0!!!
if(this.y<=container.top||this.y>=container.bottom-this.height){
this.yv*=-1;
}
}
update();
}
publicvoiddraw(Canvascanvas){
//paint.setARGB(255,128,255,50);
paint.setColor(this.color);
canvas.drawRect(this.x,this.y,this.x+this.widht,this.y+this.height,paint);
//canvas.drawCircle(x,y,widht,paint);
}
}
希望本文所述对大家的Android程序设计有所帮助。