When drawing the outline of a rectangle, the bounding
box must cover the whole pixel of the line. Otherwise
the line would be left behind when the rectangle shrinks.
This is a follow up to 248e37ac0c.
A line at 0 with 1px width should draw from 0.5 to 1.5
(cairo pixel offset). The same line with a width of 3px
is -0.5 to 2.5.
The self.intersection code calculates this correctly, subtracting
shift, the drawing code however incorrectly added it.
This fixes MIDI track grid/note offset as well as a bleed
below the track.
This reverts commit 37cae2f971.
This changes causes issues with recursive calls to the enter/leave event handling
stacks in gtk2_adour. Semantically, the change makes perfect sense, but finding
a solution to the recursion is challenging.
This is mostly a simple lexical search+replace but the absence of operator< for
std::weak_ptr<T> leads to some complications, particularly with Evoral::Sequence
and ExportPortChannel.
> This group functionality can be convenient for performing
> intermediate compositing. One common use of a group is to
> render objects as opaque within the group, (so that they
> occlude each other), and then blend the result with
> translucence onto the destination.
https://www.cairographics.org/manual/cairo-cairo-t.html#cairo-push-group
The main use case where will be to render opaque layered
[MIDI] regions transparently onto a grid.
This is never for inline references to parameters, only for starting parameter
documentation blocks. The "@p" command is for this, although unfortunately
Doxygen doesn't actually do anything with it and it's just an alias for code
text.
