turned out straightforward, in great part because the planes are
workplanes (6 DOF, represented by a unit quaternion and a point),
and therefore make it easy to get a vector in the plane, as well as
a normal.
And on that subject, replace the previous hack for parallel vector
constraints with a better hack: pivot on the initial numerical
guess, to choose which components of the cross product to drive to
zero. Ugly, but I think that will be as robust as I can get.
[git-p4: depot-paths = "//depot/solvespace/": change = 1699]
not have much motivation behind them, but they seem to work. And
make sure that we don't solve multiple times without repainting in
between, and tweak the text window a bit more.
[git-p4: depot-paths = "//depot/solvespace/": change = 1696]
and point-in-plane. These work, but the equation is still stupid,
solving everything at once and not substituting trivial equations.
[git-p4: depot-paths = "//depot/solvespace/": change = 1677]
points are now entities like any others; so a line segment request
will generate three entities, the line segment and its endpoints. I
think that's cleaner.
When I do step and repeats (and imports, and other similar), I'll
need a consistent way to assign those entity ids. That assignment
must not change if the sketch is edited. I don't have a clean way
to do that; best thought right now is to keep a record of what maps
have been used previously, and not pick a new map as long as it's
possible to use one that was used previously.
This all means that more crap gets pushed in to the Entity
structure, so that they can keep track of what solver variables
define them. Still seems better, though. I'm closer to ready
to start solving.
[git-p4: depot-paths = "//depot/solvespace/": change = 1673]