蒲立年的學習筆記 Week 10

一、用Processing寫Android程式

打開Processing，在右上角選擇添加模式

選擇Android模式

手機要設置開發人員選項，設定USB偵錯模式
就可以在Android手機上執行喽~

二、圓球碰撞模擬
這是老師的程式碼範例

void setup() {
size(500, 500);
}
float ballX=250, ballY=450, ballVX=1.3, ballVY=-10;
float ball2X=250, ball2Y=50;
void draw() {
if ( dist(ballX, ballY, ball2X, ball2Y)<100 ) {
float cx=(ballX+ball2X)/2, cy=(ballY+ball2Y)/2;
float nx=ballX-ball2X, ny=ballY-ball2Y;
line(ballX,ballY, ball2X,ball2Y);
PVector N=new PVector(nx, ny);
N.normalize();
PVector v0=new PVector(ballVX, ballVY);
float len= -N.dot(v0);
v0.add(N.mult(len*2));
line(cx,cy, cx+10*ballVX, cy+10*ballVY);
line(cx,cy, cx+20*v0.x, cy+20*v0.y);
ellipse(cx, cy, 10, 10);
stroke(0); 
line(ballX, ballY, ball2X, ball2Y);
stroke(255, 128, 0); 
line(cx, cy, cx+5*ballVX, cy+5*ballVY);
stroke(255, 128, 0); 
line(cx, cy, cx+5*v0.x, cy+5*v0.y);
stroke(255, 0, 0); 
line(cx, cy, cx+N.x, cy+N.y);
//return;
ballVX=v0.x; 
ballVY=v0.y;
}
background(255);
ballX+=ballVX; 
ballY+=ballVY;
if(ballX<50 || ballX>500-50) ballVX = -ballVX;
if(ballY<50 || ballY>500-50) ballVY = -ballVY;
ellipse(ballX, ballY, 100, 100);
ellipse(ball2X, ball2Y, 100, 100);
}
void mouseDragged(){
ball2X=mouseX; ball2Y=mouseY;
}

但其實這個程式有BUG，用滑鼠控制移動的時候有機率兩個球會黏在一起~