[DrakilorP2P]

Originally Posted by Chompy

They aren't for checking distances tho

it's to draw pretty lights

But, the only thing I mislike in those scripts is that you edit variables with the same name as the function params Only that, other then that they are very nice

Only small adjustments are required in order to check if a particular baddy have a clear line of sight to the intended target.

PHP Code:

function lineOfSight(x0, y0, x1, y1)
{
  // Things can screw up if we don't use integers.
  x0 = int(x0); y0 = int(y0); x1 = int(x1); y1 = int(y1);
  
  dx = abs(x1 - x0) << 1;
  dy = abs(y1 - y0) << 1;
  
  if (x1 > x0) ix = 1;
  else ix = -1;
  if (y1 > y0) iy = 1;
  else iy = -1;
  
  if (onwall(x0, y0)) return false;
  
  if (dx >= dy) {
    error = dy - (dx >> 1);
    
    while (x0 != x1) {
      if (error >= 0) {
        if (error != 0 || (ix > 0)) {
          y0 += iy;
          error -= dx;
        }
      }
      
      x0 += ix;
      error += dy;
      
      if (onwall(x0, y0)) return false;
    }
  }
  else {
    error = dx - (dy >> 1);
    
    while (y0 != y1) {
      if (error >= 0) {
        if (error != 0 || iy > 0) {
          x0 += ix;
          error -= dy;
        }
      }
      
      y0 += iy;
      error += dx;
      
      if (onwall(x0, y0)) return false;
    }
  }
  
  // Success
  return true;
} 


If you want distance with that, add a counter or employ trigonometry in a separate function.