These points can be used for constraining the width of the text
(or to the width of the text).
The main parts of the commit are:
* TtfFont is restructured to be able to return the aspect ratio
for a given string.
* This aspect ratio is written to the savefile, such that even if
the font is missing, the sketch would still be solved correctly.
* The two additional points are constrained via perpendicularly
to the two main points (which form a v vector).
The compatibility features are as follows:
* When the font is missing in old files, 1:1 aspect ratio is used,
which works for the replacement symbol anyhow.
* When the two additional points are missing in old files, their
would-be positions are calculated and they are moved there,
avoiding 'jumping' of underconstrained sketches.
Before this commit, a translate group based on another translate
group would always use the "union" boolean operation, which does not
work at all if one wants an array with a difference operation, and
results in degraded performance if one wants an array with
an assemble operation.
This significantly improves performance e.g. in case of a sketch
containing a multitude of wooden panels, as the meshes can be
merely transformed instead of being joined.
The states are:
* Draw all lines (on top of shaded mesh).
* Draw occluded (by shaded mesh) lines as stippled.
* Do not draw occluded (by shaded mesh) lines.
As usual, the export output follows the screen output.
In 2.0, the distance between the points in the TTF request specified
cap height. In 2.1, that was accidentally changed to some arbitrary
value near cap height instead, due to a 72pt factor mess-up.
This commit restores the old behavior.
If SolveSpace crashes after the open, or hangs and is forcibly
killed, data would be lost. (I lost my data.) Instead, remove
autosave only in two cases: right after a successful save, or right
after a save is declined. This should be completely safe.