Too bad, you cannot see the grid on the picture I sent before. The lines are starting at the center of the cells and the dot is at the end of the line pointing into the direction. I attached another picture with different sized vectors and a visible grid. A T would probably be faster. I have tried a rectangle instead of the dot before, but this looked rather confusing. Christian On 01.10.2015 18:20, Sean Luke wrote: > Do you think the dot should be at the center of the cell? That is, a > maximum-length line would be half the width of the cell? Or should > the center of the cell be the center of the line? > > If speed is at issue, a small orthogonal line, like a T, would be a > bit faster than a dot; might do that. > > Sean > > I also note from below that your class is basically a replacement for > OrientedPortrayal2D: it can be used (and from the picture, appears to > be used) in ContinuousPortrayal2D, for example. >