Week17

W17-01虎克定律的彈簧

背景顏色、畫線

~~程式碼~~

void setup(){

  size(300,300);

}

float x=100,y=150,vx,vy;

void draw(){

  background(#002966);

  stroke(#b7efff);

  line(x,y,200,150);

  

  fill(#b7efff);

  ellipse(x,y,13,13);

  ellipse(200,150,13,13);

  if( ! mousePressed){

    float dx=x-200;

    float dy=y-150;

    float len=sqrt(dx*dx+dy*dy);

    float f=(len-100);

    dx /= len;

    dy /= len;

    vx -= f*dx*0.01;

    vy -= f*dy*0.01;

    x += vx;

    y += vy;

    //x -= dx*(len-100)/len*0.1;

    //y -= dy*(len-100)/len*0.1;

  }

}

void mouseDragged(){

  x=mouseX;y=mouseY;

}