【互动媒体创意编程3】小球弹跳：震荡

秒速五厘米 2023-06-27 06:22 34阅读 0赞

## 【互动媒体创意编程3】小球弹跳：震荡 ##

首先老规矩先放效果：  
![在这里插入图片描述][20200104212251347.gif]  
我们需要在随机的位置生成小球且赋予他们一定的质量。  
小球的质量决定了小球的重量。根据物理原则，mg = ma。故每个小球的加速度就是我们设置地g。  
在固定的位置放置小球，之后再draw()中调用函数计算当前帧的速度和小球位置。  
没有什么特别的。在上一章里讲过了，再说就没有意思了。  
直接贴代码：

PVector p1,p2,p3,p4,p5;
    PVector m,n;
    PVector mouse;
    PVector e;
    PVector circle;
    float t;
    float a;
    float color1,color2,color3;
    PVector v[]=new PVector[30];
    PVector location[]=new PVector[30];
    
    float x; 
    float y; 
    float yspeed = 0; 
    float xspeed = 0; 
    float balldiameter = 10; 
    float ballradius = balldiameter/2; 
    
    
    
    void setup(){
        
      size(800,800);
      p1=new PVector(0,500);
      p2=new PVector(800,500);
      for(int i=1;i<20;i++){
        
    
        location[i]=new PVector(random(800),random(300));
        v[i]=new PVector(random(5),random(10));
      }
      
    }
    void draw(){
        
     
      background(255);
      strokeWeight(1);
      
       mousemouvement();
       boundary(); 
       Ball();
      
      
      PVector vec = PVector.sub(p1, p2);
      vec.normalize();
      n = new PVector(-vec.y, vec.x);
      n.normalize();
      //line(p1.x,p1.y,p2.x,p2.y);
      noFill();
      mouse=new PVector(mouseX,mouseY);
      //ellipse(mouse.x,mouse.y,300,300);
      float d = n.dot(p1);
      PVector temp=PVector.mult(n,d-PVector.dot(mouse,n));
      p3=PVector.add(mouse,temp);
      //line(p3.x,p3.y,mouse.x,mouse.y);
      color1=random(250);
      color2=random(250);
      color3=random(250);
      fill(color1,color2,color3);
      //ellipse(p3.x,p3.y,15,15);
      fill(color3,color2,color1);
      //ellipse(mouse.x,mouse.y,15,15);
      
      m=PVector.sub(p2,p1);
      m.normalize();
      e=PVector.sub(mouse,p1);
      a=PVector.dot(e,m);
      t=a-sqrt(22500-(PVector.dot(e,e)-a*a));
      p4=PVector.add(p1,PVector.mult(m,t));
      p5=PVector.add(p1,PVector.mult(m,t+sqrt(22500-(PVector.dot(e,e)-a*a))*2));
      
      
      float j=PVector.sub(mouse,p3).mag();
      fill(0);
      ellipse(p5.x,p5.y,16,16);
      ellipse(p4.x,p4.y,16,16);
      strokeWeight(4);
      //line(mouse.x,mouse.y,p1.x,p1.y);
      //line(mouse.x,mouse.y,p2.x,p2.y);
      noFill();
      for(int i=1;i<20;i++){
        
      location[i]=location[i].add(v[i]);
      if(location[i].x>=790||location[i].x<=10)
        v[i].x=-v[i].x;
        if(location[i].y>=490||location[i].y<=10)
        v[i].y=-v[i].y;
      ellipse(location[i].x,location[i].y,40,40);}
       
    }
    
    void mousemouvement(){
        
    if(mousePressed==true){
        
    x=mouseX;
    y=mouseY;
    yspeed = mouseY-pmouseY;
    xspeed = mouseX-pmouseX;
     
    }
    }
    
    void boundary() {
         
    if (y >= height - ballradius) {
         
    y = height - ballradius; 
    yspeed = -yspeed/1.1; 
    } 
    if (y <= ballradius) {
         
    y = ballradius; 
    yspeed = -yspeed/1.35; 
    } 
    if (x >= width -ballradius) {
         
    x = width -ballradius; 
    xspeed = -xspeed/1.10; 
    } 
    if (x <= ballradius) {
         
    x = ballradius; 
    xspeed = -xspeed/1.10; 
    } 
    } 
    
    void Ball() {
         
    if (balldiameter < 2) {
         
    balldiameter = 2; 
    } 
    if (balldiameter > 400) {
         
    balldiameter = 400; 
    } 
    ballradius = balldiameter/2; 
    background(254);
    
    fill(#1C86EE);
    ellipse (x,y,50,50); 
    
    yspeed = yspeed += 0.2; 
    xspeed = xspeed/1.1; 
    y = y + yspeed; 
    x = x + xspeed; 
    }

--------------------

[【互动媒体创意编程0】柏林噪声生成的随机地形][0]  
[【互动媒体创意编程1&2】万千星河都涌向你：向量、速度、力与加速度][1_2]  
[【互动媒体创意编程4】processing中用粒子系统实现的烟花][4_processing]

[20200104212251347.gif]: https://img-blog.csdnimg.cn/20200104212251347.gif
[0]: https://blog.csdn.net/Ha1f_Awake/article/details/103835992
[1_2]: https://blog.csdn.net/Ha1f_Awake/article/details/103837101
[4_processing]: https://blog.csdn.net/Ha1f_Awake/article/details/103837924