Arrowparallel

[Cyrille Piatecki]

In Arrowparrallel, the direction of the arrow is determined par the order of the point which are use for the construction of the line. I think it would be better to have a key word to decide the direction.

Also I have not found a way to decide of the lenght of the Arrow. It stop at the border of the canvas.

Is there a solution ?

[Cyrille Piatecki]

I would like to add that in bisector command or bisectorlines command, I have not found a way have only a segment  and not a line and in the case of bisector lines to have onlty one line.

[Alfred Wassermann]

Thank you very much for informing about this annoyance.

Meanwhile, arrowparallel is a very special element. Since a few years its usefulness may be limited:

in fact, it is just a parallel segment with an arrow head. In former times the underlying parallel line was constructed by 1) creating a parallel point element, 2) creating a segment

through the parallel point and the supplied point.

Meanwhile, parallel lines are constructed using the cross product between the given line and the line at infinity (working projectively).

That means the second point of the parallel line is always infinitely far away. Therefore, arrowparallel is in fact a ray.

We have to think if we can reverse this and make the arrow parallel a finite segment again.

As a workaround, I suggest to use a parallelpoint and create a segment with lastArrow through the two points.

Best wishes,

Alfred

[Alfred Wassermann]

Bisectorlines is an element which consists always of two lines.

Bisector: this element always contains a helper point which defines the line and has distance 1 from the center. you can see it. e.g with

var li = board.create('bisector', [p1, p2, p4], {straightFirst: false, straightLast: false, point: {visible:true}});

At the moment, if you want a different length of this segment, the bisector line has to be intersected with a circle.

The question is, if we allow to set the distance from the center point for this point or search for other, more general possibilities for segments.

What do you think?

Best wishes,

Alfred