gistfile1.py

    def inLos(self, x1, y1, px, py):
        """Checks if point is in LOS"""
        x2 = px
        y2 = py
        if FAST_LOS:
            self.gamemap[x1][y1].changed = True
            issteep = abs(y2 - y1) > abs(x2 - x1)
            if issteep:
                x1, y1 = y1, x1
                x2, y2 = y2, x2
            if x1 > x2:
                x1, x2 = x2, x1
                y1, y2 = y2, y1
            deltax = x2 - x1
            deltay = abs(y2 - y1)
            error = int(deltax / 2)
            y = y1
            ystep = None
            if y1 < y2:
                ystep = 1
            else:
                ystep = -1
            b = False
            for x in range(x1, x2 + 1):
                if b:
                    return False
                if issteep:
                    if not self.gamemap[y][x].type[1]:
                        b = True
                else:
                    if not self.gamemap[x][y].type[1]:
                        b = True
                error -= deltay
                if error < 0:
                    y += ystep
                    error += deltax
            return True
        else:
            b = False
            ret = True
            line = self.getLine(py, px, y1, x1)
            for j in line:
                if b:
                    ret = False
                jx = j[1]
                jy = j[0]
                if not self.gamemap[jx][jy].type[1]:
                    b = True
            self.gamemap[x1][y1].changed = True
            return ret