/* 
 
  358. A 12" (30 cm) grid covering the wall. 
  Within each 12" (30 cm) square, one arc from 
  the corner. (The direction of the arcs and 
  their placement are determined by the draftsman.) 
  
  (Inches must be translated into pixels) 
  
  Implemented as software by Casey Reas <http://groupc.net> 
  March, 2004 
  Processing v.68 <http://processing.org> 
 
*/ 
 
void setup() 
{ 
  size(800, 600); 
  noFill(); 
  stroke(255); 
  background(0); 
  framerate(4); 
} 
 
int res = 50;   // Resolution of grid 
int arcres = 48; // Resolution of the arc 
 
void loop() 
{ 
  background(0); 
  for(int i=0; i<height; i+=res) { 
    for(int j=0; j<width; j+=res) { 
      int r = int(random(4)); 
      if(r == 0) { 
        arc_0(j, i, res); 
      } else if (r == 1) { 
        arc_1(j, i, res);        
      } else if (r == 2) { 
        arc_2(j, i, res);      
      } else if (r == 3) { 
        arc_3(j, i, res);        
      } 
    } 
  } 
} 
 
void arc_0(int xC, int yC, int r) 
{ 
  int x = 0, y = r, u = 1, v = 2 * r - 1, E = 0; 
  while (x < y) { 
    thin_point(xC + y, yC - x + res); // ESE 
    x++; E += u; u += 2; 
    if (v < 2 * E){ 
      y--; E -= v; v -= 2; 
    } 
    if (x > y) break; 
    thin_point(xC + x, yC - y + res); // SSE 
  } 
} 
 
void arc_1(int xC, int yC, int r) 
{ 
  int x = 0, y = r, u = 1, v = 2 * r - 1, E = 0; 
  while (x < y) { 
    thin_point(xC + x, yC + y); // NNE 
    x++; E += u; u += 2; 
    if (v < 2 * E){ 
      y--; E -= v; v -= 2; 
    } 
    if (x > y) break; 
    thin_point(xC + y, yC + x); // ENE 
  } 
  
} 
 
void arc_2(int xC, int yC, int r) 
{ 
  int x = 0, y = r, u = 1, v = 2 * r - 1, E = 0; 
  while (x < y) { 
    thin_point(xC - y + res, yC + x); // WNW 
    x++; E += u; u += 2; 
    if (v < 2 * E){ 
      y--; E -= v; v -= 2; 
    } 
    if (x > y) break; 
    thin_point(xC - x + res, yC + y); // NNW 
  } 
} 
 
void arc_3(int xC, int yC, int r) 
{ 
  int x = 0, y = r, u = 1, v = 2 * r - 1, E = 0; 
  while (x < y) { 
    thin_point(xC - x + res, yC - y + res); // SSW 
    x++; E += u; u += 2; 
    if (v < 2 * E){ 
      y--; E -= v; v -= 2; 
    } 
    if (x > y) break; 
    thin_point(xC - y + res, yC - x + res); // WSW 
  } 
} 
 
void thin_point(int x, int y) 
{ 
  point(x, y); 
}