This uses the graph_width to get the proper time range of the
visualizer row. Mostly, this is just complicated because we
the ticks to be an overlay rather than inline with the list
rows.
We can avoid using the inline scrollbar in favor of overlay
scrolling if we bridge the adjustment into the GtkViewport.
This sadly requires us to subclass things to get it just
right.
When changing the zoom (zooming out), we could potentially
let the scrollbar be past the end. This looks pretty bad when
the GtkWindow doesn't clip correctly.
This just adjusts things so we push ourselves back into the
visible area.
We need to take into account the real start of the capture to
land the ticks in the right position. Add "epoch" concept
to SpVisualizerTicks for just this purpose.
Generally we want this thing hidden, so only show it if we have
zoomed in enough to cause it to be useful.
We need to also find a way for the container to be able to
handle the change in size request and adjust the GtkPaned
to be non-ugly.
There are lots of little things that need fixing, such as the
ticks positioning, and reusing surfaces as much as possible, but
this gets our "MVP" panning in place.
If we don't have a minute worth of input, we should shrink the
visible area to exactly what we came across.
We still have the issue of the UI creating the capture file
before auth has completed, but we can fix that later so we
have a "semantically" correct start time.
These signals are emitted when a visualizer row has been added
or removed from the view. This might be handy if you want to
resize a paned based on the natural size of the visualizers.
This adds a new helper widget SpVisualizerView to simplify using
visualizers from applications using libsysprof-ui-2 such as
Builder.
We can manage the view range, zoom, etc from this widget going
forward.
