openlayers/openlayers — pull request #783 by mwa (2012-12-04 12:14:26+00:00)
Title: Add construction tools for digitizing (arc intersection, orthogonal lines)

I have created two new digitizing tools for geometric construction of features.

* Arc intersection control

Select two points and a radius for each to construct the intersection point(s) of the two circles.

* Orthogonal lines control

Select two points defining a base line and distances along and perpendicular to the base line to construct an orthogonal linestring starting from the first point.

There are examples and unit tests for both controls.

see also http://trac.osgeo.org/openlayers/wiki/ProjectsUnderDev/ConstructionTools