In order to properly determine the scaling of an ncvisual to
be rendered, ncvisual_geom() needs know the blitting method.
For this reason, it took an ncblitter_e argument. It also,
however, needs handle degradation, which means knowing whether
NCVISUAL_OPTIONS_NODEGRADE is in use. It thus really wants the
struct ncvisual_options. Pass and accept it. Closes#697, and
fixes the "yield" demo in ASCII mode (#696).
If we're in ASCII mode, no blitter except for NCBLIT_1x1 is going to
work. Whenever NCBLIT_DEFAULT is provided, select NCBLIT_1x1 if we're
in ASCII mode. Add NCVISUAL_OPTIONS_MAYDEGRADE and
NCPLOT_OPTIONS_MAYDEGRADE. Both serve to allow smooth degradation when a
blitter other than NCBLIT_DEFAULT has been provided. Closes#637.
Make calc_gradient_cell() static inline so our templated ncppplot
implementation can use it (ugh). When using NCBLIT_1x1 for plots in
ASCII mode, use space rather than full block, and invert colors.
Use NCBLIT_DEFAULT in the demo for the FPS plot.
This represents an essentially complete rewrite of ncvisual and associated code. It had two major goals:
Improve the ncvisual API based off lessons learned, pursuant to the upcoming API freeze. In particular, I wanted to:
decouple ncvisuals from ncplanes. It should be possible to render a ncvisual to multiple planes, with different scaling each time. It should be possible to create an ncvisual without a plane, etc.
normalize the various ways of constructing an ncvisual -- file, memory, plane, etc.
Support multiple blitters, from 7-bit ASCII to Sixel. This required writing the blitters in several cases, and they're not yet in their final implementations (but the API is fine)
I have not yet unified Plots and Visuals, and might not, given that the Plot code works fine. We could at this point implement Plots in terms of Visuals, though -- the blitter backend range has been unified. Sixel is not yet implemented, though it is listed.
There is a new POC tool, blitter. It renders its arguments using all possible blitter+scaling combinations. Another new POC, resize, displays its argument, then resizes it to the screen size and displays that, explicitly making use of ncvisual_resize() rather than a scaling parameter to ncvisual_render().
This also eliminates some memory leaks and bugs we were seeing in trunk, and brings in Sixel scaffolding.
The C++ wrapper will also need patching back up; I cut most of it down while wrestling with this crap, urk.
Closes#638, #562, and #622.
nick black