week 7. Project 1 demo & using sin(x)

sample codes:

float radius;
int segment = 10;
float centerX;
float centerY;

void setup(){
 size(600,600);
 background(0);
 stroke(255);
 centerX = height/2;
 centerY = width/2;
}

void draw(){
  background(0);
  radius = dist(centerX, centerY, mouseX, mouseY);
  spiral(centerX,centerY,radius,segment);
}
void spiral(float x_c,float y_c, float r, int seg){
    for(int i =0;i<=seg;i++){
      float x = x_c+cos(i*2*PI/seg)*r;  //算出x的位置
      float y = y_c+sin(i*2*PI/seg)*r;  //算出y的位置
      point(x,y);  // 畫出點，也能用其他形狀
    }
}



EX:
1. 每次點擊滑鼠，劃一個隨機半徑大小的圓。
2. draw flower of life (生命之花)

reference:

https://processing.org/examples/sine.html

https://processing.org/examples/sinecosine.html

John Whitney
https://www.youtube.com/watch?v=BzB31mD4NmA

https://www.youtube.com/watch?v=s_KIrIJkLoE