This commit introduces support for inverting all types of cursor.
To invert the display without re-rendering any text, we draw the cursor
into a command list and then compose the command list with the existing
renderer using the MASK_INVERT composition flag.
This wouldn't normally work with our renderer because there is no
_background_ color to invert in some cases (such as when acrylic is in
use.)
To work around that, we're taking advantage of @zadjii-msft's two-pass
cursor renderer.
To properly invert the cursor over a transparent background:
(Examples are given below for two cursor types, but this applies to all
of them.)
First, we'll draw a "backplate" in the user's requested background color
(with the alpha channel set to 0xFF). (`firstPass` == true)
EMPTY BOX FILLED BOX
===== =====
= = =====
= = =====
= = =====
===== =====
Second, the glyph is drawn (outside of the cursor renderer).
EMPTY BOX FILLED BOX
==A== ==A==
=A A= =A=A=
AAAAA AAAAA
A A A===A
A===A A===A
Last, we'll draw the cursor again in all white and use that as the
*mask* for inverting the already-drawn pixels. (`firstPass` == false) (#
= mask, a = inverted A)
EMPTY BOX FILLED BOX
##a## ##a##
#A A# #a#a#
aAAAa aaaaa
a a a###a
a###a a###a
Related to #9610
## Validation Steps Performed
Manual visual validation in all configurations.
4b7d955012