TitleBar and PhoneShell have drawn >_ knocked out of a solid accent tile since
v2, and both say in a comment that the launcher icon draws the same thing so the
three cannot drift. The launcher was still v1: an outlined square in the accent.
The comments are true now.
On Android the tile is the background layer rather than a rounded rectangle in
the foreground, because the rounding a launcher applies is its mask. Drawing the
tile would put a second rounded shape inside the mask, clipped at the corners on
any device whose mask is not the one it was drawn for; leaving it to the mask
gets a squircle on one device and a circle on another for free. Windows has no
mask, so dodossh.ico still draws its own corners.
The monochrome layer keeps only the glyph. A themed icon drops the background,
which is where the tile now lives, and a layer filled to the edges to stand in
for it would tint to a featureless square.
The glyph is half the width of the safe zone, taken from the two headers rather
than invented -- both set >_ a little under half the tile across. It is also
markedly more legible small than the outline was: dark on accent at 16px is a
mark, where a sub-pixel hairline was a smudge.
The window had no icon and the executable had no icon, so Windows drew its
generic one in the taskbar, in alt-tab and in Explorer, next to an application
that draws its own titlebar precisely so that nothing about it looks borrowed.
The geometry is the launcher vector's, mapped so the middle 72 of its 108-unit
viewport fills the canvas: that 72 is what an adaptive icon actually shows, and
rendering the full 108 would draw the mark at 39% of the width. Nine sizes,
because Windows asks for several and downsamples unkindly when one is missing,
and a floor of one pixel on the strokes so 16px is a mark rather than a smudge.
Windows takes an .ico and nothing else, so the raster the phone does not need
exists here. dodossh-icon.ps1 sits beside it and draws it from those same
numbers, so the two heads still have one geometry between them.
jaap-jan