當新形狀在加工時形成不規則形狀

Question

我想在形成新形狀時使舊形狀消失。請幫幫我。基本上，我想在點擊時創建一個矩形，但當我再次點擊時，圓圈應該消失。這應該以相等的概率發生。

void setup() 
{ 
    size(400, 400); 
    background(255); 
} 

void draw() 
{ 
    fill(255); 
    tileAp();  
} 

void tileAp() 
{  
    if (mousePressed && mouseY >= 0 && mouseY <= 200) 
    {  
     drawM(true); 
    } 
    else 
    {  
    } 
} 

void drawM(boolean b) 
{ 
    int prob = int(random(0, 2)); 
    if (b == true) 
    { 
     if (prob == 0) 
     { 
      rect(mouseX, mouseY, 50, 50); 
     } 

     if (prob == 1) 
     { 
      ellipse(mouseX, mouseY, 50, 50); 
     }  
    } 
} 

Answer 1

像suggested duplicate說，你需要調用background()功能來清除舊的框架。

比較一下素描：

<script src="https://cdnjs.cloudflare.com/ajax/libs/processing.js/1.6.6/processing.min.js"></script> 
 
<script type="application/processing"> 
 

 
void setup(){ 
 
    size(200, 200); 
 
    background(64); 
 
} 
 

 
void draw(){ 
 
ellipse(mouseX, mouseY, 20, 20); 
 
} 
 

 
</script> 
 
<canvas> </canvas>

這一個：

<script src="https://cdnjs.cloudflare.com/ajax/libs/processing.js/1.6.6/processing.min.js"></script> 
 
<script type="application/processing"> 
 

 
void setup(){ 
 
    size(200, 200); 
 
} 
 

 
void draw(){ 
 
background(64); 
 
ellipse(mouseX, mouseY, 20, 20); 
 
} 
 

 
</script> 
 
<canvas> </canvas>