Resolves#410. notcurses_at_yx() accepted a cell*, but the
gcluster of this cell was always set to 0. The EGC is instead
a heap-allocated copy, returned as the primary return value.
This is due to the absence of an egcpool to bind against.
Existing callers can be converted thus:
* instead of passing cell 'c', pass &(c)->attrword, &(c)->channels
* either initialize 'c' with CELL_TRIVIAL_INITIALIZER, or set its
gcluster field to 0 following the call
I've updated all calls from tests/demos, updated the docs, and
updated the C++ and Python wrappers.
Add ncplane_bound(3). This allows a new plane N to be created in the
*bound* state relative to another ncplane B. If B moves, N moves the
same amount. If N is moved, the coordinates are taken relative to B
as opposed to the standard plane. If B is destroyed, N is destroyed.
Each plane can have many planes bound to it, but can only be bound to
a single plane. Add ncplane_reparent(3). This allows a plane to be
detached from any plane to which it is bound, and optionally rebound
to a new plane. The standard plane cannot be reparented.
Documentation and unit tests have been added for both.
ncvisual_render() now returns the number of cells emitted
rather than just 0/-1. -1 is still returned on failure.
Rather than 0 for length meaning "all possible length", it
now means 0, and -1 means "all possible length". All demos,
tests, and PoCs have been updated. #422
ncplane_mergedown() is similar to the "Merge down" operation
in the GIMP. It writes to the destination plane the result
of rendering the source and destination frames per se.
Add four new fields to notcurses_options: margin_{tblr}, which requests margins to the top, right, bottom, and left. Render only within those margins, leaving the screen otherwise untouched (well, cleared if using the alternate screen). #293