//FOV CODE


bool raycast(int sx, int sy, int sh, int tx, int ty, int th)
{
  int x = sx;
  int y = sy;

  int dx = tx - sx;
  int dy = ty - sy;
  if (dx == 0 && dy == 0) return false;
  float cdx = 10000.0;
  float cdy = 10000.0;
  if (dy != 0)
  {

    cdx = IntToFloat(dx)/IntToFloat(dy);
    if (cdx < 0.0) cdx = -cdx;
  }
  if (dx != 0)
  {

    cdy = IntToFloat(dy)/IntToFloat(dx);
    if (cdy < 0.0) cdy = -cdy;
  }

  float D = Maths.Sqrt(IntToFloat(dx*dx + dy*dy));

  // distance
  float fx = 0.0;
  float fy = 0.0;

  // initial steps to get from the center of the tile to lines
  float hdx = 0.5*cdx;
  float hdy = 0.5;
  float vdx = 0.5;
  float vdy = 0.5*cdy;

  int xstep = 1, ystep = 1;
  if (dx < 0) xstep = -1;
  if (dy < 0) ystep = -1;

  bool done = false;
  while (!done)
  {

    if (hdx < vdx)
    {
      //HIT H
      fx += hdx;
      fy += hdy;

      vdx -= hdx;
      vdy -= hdy;

      hdx = cdx;
      hdy = 1.0;

      y += ystep;
    }
    else
    {
      //HIT V
      fx += vdx;
      fy += vdy;

      hdx -= vdx;
      hdy -= vdy;

      vdx = 1.0;
      vdy = cdy;

      x += xstep;
    }
    // dcalc
    float d = Maths.Sqrt(fx*fx + fy*fy);
    float h = IntToFloat(sh) + (d/D)*IntToFloat(th - sh);
    int index = Map.Index(x, y, 0);
    int tileType = tiles[index];
    if (!TileInfo[tileType].Walkable)
    {
      return false;
    }
    else if (x == tx && y == ty)
    {

      return true;

    }
  }
}

void DoFov(int sX, int sY, float x, float y,  int radius)
{
  int i;
  float ox,oy;
  ox = IntToFloat(sX)+0.5;
  oy = IntToFloat(sY)+0.5;
  while (i < radius){
    int ix = FloatToInt(ox, eRoundDown);
    int iy = FloatToInt(oy, eRoundDown);
    if (!Map.Sane(ix, iy)) return;
    int index = Map.Index(ix, iy, 0);

    //tileMask[tileIndex(FloatToInt(ox, eRoundDown), FloatToInt(oy, eRoundDown))] = 1;//Set the tile to visible.
    //if(tiles[index].Height - tiles[tileIndex(pos.X, pos.Y)].Height > 1) return;
    if (raycast(sX, sY, 1, ix, iy, 1)) {
      tileMask[index] = 1;
    }

    ox+=x;
    oy+=y;
    i++;
  }
}

static void Map::SetFOV(int sX,  int sY, int radius)
{
  float x,y;
  int i;
  ClearTileMask();
  while (i < 360){
    x = Maths.Cos(IntToFloat(i) * 0.01745);
    y = Maths.Sin(IntToFloat(i) * 0.01745);
    DoFov(sX, sY, x, y, radius);
    i+=1;
  }
}