Implement true color support define in:
https://en.wikipedia.org/wiki/ANSI_escape_code
The sequence is:
ESC[ … 38;2;;; … m Select RGB foreground color
ESC[ … 48;2;;; … m Select RGB background color
A character cell can only be either narrow or wide. It's more
convenient to represent that as an int containing 1 or 2, but slightly
more correct to represent it as a "boolean" single-bit integer.
The terminal framebuffer was not resetting the wrap state of a row
when a previously-wrapping line was overwritten by a non-wrapping
line. Restore previous, subtle behavior of line wrap. Fix wrap
verification bug now exposed by emulation-wrap-across-frames.test.
Also hoist some getters, mostly for clarity.
Fixes#820.
Add another round-trip verification. For both original and generated
state, generate a diff from an initial, empty state. Verify that
these two diffs are the same.
The problem was that the round-trip verification code copies the
current state, which may contain intermediate Parser state for
multibyte characters and ANSI escape sequences. It then applies diffs
to that copy, which may appear as badly formed input.
Also removes some dead, never-used code.
* Refactor put_cell() and parts of new_frame(), and associated state, into put_row().
* Optimize display and line wrap handling code/output.
* Make last_frame a const ref, to eliminate a costly copy of the framebuffer on every screen refresh.
* In new_frame()'s scroll optimization, don't copy rows, use pointers instead.
* Don't check entire frame buffer for scrolling if first line hasn't scrolled.
* Add a generation counter on Row objects to allow quicker/better identification of scroll regions
* Use at() for bounds-checking on framebuffers, because they can be resized.
* Copy and resize scroll buffer on window resize.
* Reduce the size of Terminal::Cell.
* Change colors and attributes in Terminal::Rendition to bitfields/bitmask.
* Change Cells to use UTF-8 strings instead of vector<wchar_t>. Store Rows in a vector instead of a deque.
* Add various Framebuffer::append() methods for more efficient passing of single and repeated characters.
* Change title/icon strings from deques to a vector typedef-- this is more for tidiness than any real performance.
* Fix inefficient STL use around Parser::UTF8Parser.
* Reduce typeid() usage, change some of it to a virtual method
* Do multiple-line scrolls as a single move
terminalfunctions.cc: set_if_available() was undeclared.
Fix printf() wint_t/wchar_t warnings.
mosh-server.cc: Fix warning for side effects inside typeid().
Signed-off-by: John Hood <cgull@glup.org>