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. On Oct 1, 2015, at 12:13 PM, Christian Meyer <[log in to unmask]> wrote: > You are right about Oriented2D and Scaled2D, they should not be > implemented by Double2D. I am just using a line with a dot at the end to portray the directions without any transformations. That is quite a different approach which might not fit well into VectorPortrayal2D because it uses its own shape. > > I attached my class and how the direction vectors look like. > Christian