`set_math_channels()` rebuilt the store for any change, and a rebuild replaces the buffer:
every channel in the window started again, which is the "modifying one expression invalidates
all the others" report.
The plan is a *partition over the channels*, so it only moves when the set moves. When the
set is unchanged -- same channels, names and enables -- nothing is rebuilt now: the store is
untouched, every other channel keeps its samples and its runtimes, and the surgical path
prepares and recomputes only the affected graphs. The affected set is the edited channels plus
whatever *names* them, because one channel's output is another's input, and the recompute
computes the whole list in order (the inputs have to be there) while writing only those in
the mask -- which is why the step-loop is now `math_apply_locked(sample, write_mask, timed)`.
Adding, removing or renaming a channel still moves the plan, and still rebuilds.
[math-probe] graph edit: stored_slots 800 -> 900 (want the second at least the first, and non-zero)
The count grows because the stream keeps filling while the edit runs; the point is that it
never falls to 0, and that every channel afterwards still reads `N samples vs M time slots`
with N == M.
The switch in the signal list means "do not acquire this", and until now a trace of it
stayed on its plot drawing nothing: a slot that holds one of the four a plot has, reads
`--`, and blocks the drop that would fill it with something live.
`on_signal_switch()` now clears every slot that holds that signal, by the **signal name**
the slot remembers -- never the channel index, which is what the enable change renumbers --
and says what it did: `'sine' is off: 1 trace left the plots`. The follow-ups (a relayout,
the panels' chips, the layout save) happen once rather than per slot.
Re-enabling deliberately does not put the traces back: the arrangement is the user's, and
guessing where they were is worse than leaving them off. Say the word if you want that
direction too.
[enable-all-probe] reads it end to end -- it enables every signal, assigns the channels
across the rows, then switches one off *through its own acquire tick*:
[enable-all-probe] switched 'sine' off: traces_left=0 (want 0) notice=''sine' is off: 1 trace left the plots'
which is also why the notice shares the status line's warning styling from the previous
commit: the trace leaving the plots is something the user should see happen.
The refusal was never silent -- `on_drop_channel()` has always set a notice -- but the
status bar renders `notice + " | " + glance` in one label, so "plot 1 already holds
four signals" arrived looking like part of the routine text a reader skims, which is the
"no clear user feedback" report. The probe's own reading showed it plainly: the label held
`plotting 'sine' on plot 1 | live · 4.44 kS/s · 2 s window`.
Three changes:
- While a notice is fresh the status label carries the stock `.warning` class, so a message
looks like a message and the class goes when the notice does. Every notice benefits, not
just this one.
- The refusal says what to *do*: "plot 1 holds four signals already: drop it on another
plot, or add a row with the layout editor (L)".
- The drop's inline notice now goes through `set_notice()`, the one setter, instead of
writing `app.notice` and its deadline by hand.
[drop-probe] reads the whole path, with the row filled first so the drop under test is the
refusal:
full row refused the drop: 0 (want 0)
refused feedback: notice='plot 1 holds four signals already: ...' warning=1
the status line, composed: warning=1 status='plot 1 holds four signals already: ... | live · 9.97 kS/s · 2 s window'
The label is read in the third line and not the second on purpose: the status line composes
the notice into itself on its own cadence, so a beat after the refusal it may still hold the
previous text -- which the first attempt at this reading mistook for the fix not working.
The row limit is not silent in the same way: the layout editor's `+` is insensitive at
`kMaxRows`, which is a control that says "no" by being unusable rather than a message.
The window control is a GtkMenuButton whose popover autohides -- which works for as long as
GTK holds the popover's grab, and the grab is what can go missing: a window manager moving
it, the nested popover the unit dropdown opens taking it, and every headless run, where
there is no manager to hand one out at all. After that a click anywhere else in the window
leaves the bubble up, which is the "sometimes it is awkward to close" report.
`on_window_popover_press()` states the rule outright instead of relying on the grab: any
press that reaches the window's own surface closes it. That needs no hit test beyond the
button -- a popover is its own surface, so a click *inside* it never arrives here -- and the
button is left alone, because its own click is the toggle that closes it. The press gesture
is on the window in the capture phase, so a widget under the press (the plot's own gestures
among them) cannot hide it.
[windowpop] reads both halves, with autohide turned off for the probe -- the state a user
meets when the grab goes missing:
[windowpop] opened=1 visible=1 click_gestures=2
[windowpop] after a press elsewhere: active=0 (want 0)
[windowpop] after a press on the button: active=1 (want 1)
`click_gestures` is read as well as the handler, so "the rule works" and "the rule is
connected" are two facts rather than one.
Moving the editor's frame into math-editor.ui left `math_body` and `math_actions` as
<child> elements of the *window* rather than of `math_outer`, because those edits were
anchored on the file's tail and closed the outer box two elements early. A GtkWindow
takes exactly one default <child>, so nothing failed loudly: the body -- with the canvas
and the parameter form inside it -- was left parentless, visible but never mapped, 0x0,
drawing nothing. Two symptoms, one cause: the canvas is blank, and the window is sized
around the head row and the buttons alone.
Measured against the pre-move revision in a worktree, same probe, same environment:
before this fix `canvas=0x0 mapped=0 window=756x940`; after it `canvas=420x836 mapped=1
window=938x940`, which is the old revision's own reading exactly.
It survived because that slice's probe read the editor's *values* (nodes, gain, output,
name, unit) and nothing about its structure. Every other panel moved that day has a
structural reading -- `controls_inside=13/13`, `nested=1`, `labels=2 list=1` -- and none
of them was affected. `[math-probe] editor frame:` is that reading now: the canvas's
allocation, its mapped state, and whether the canvas and the name entry are inside the
dialog at all, delayed 500 ms because an allocation only exists after a layout. In the
broken build it read `0x0 mapped=0 in_dialog=0`.
check_ui passes both files: the XML was valid and every property type-checked.
The second half of this plan row, and the half of that dialog which is template.
src/ui/math-editor.ui holds the window (its size and modality), the box around it,
the identity row -- the name and the unit -- and the body with the canvas in it.
What stays in code is the drawing: the canvas is a GtkDrawingArea the file *declares*
and the code draws, with the gestures that make it a graph editor, and the parameter
form follows which node is selected. The palette and the buttons go next.
The builder is held on `App` and cleared on the *next* opening rather than with the
window: the window belongs to the builder's object list, so freeing the builder under a
live window frees the window with it. That is the source form's pattern, and the probe's
close-then-reopen path is what exercises it -- `reopened: dialog=ok, nodes=2`.
The identity row is read back too, since a `.ui` can hold the widget but not the value:
`dialog build: ... name='math3' unit='' ...`, the entries having been filled from the
channel being edited. check_ui is at 12 ok, 0 failed.
Fifteen display strings in the two preference forms were written as GTK mnemonics -- `_Directory`,
`_Server`, `Multicast _group`, `_Theme` and the rest -- but the property that makes GTK read them was
never set, so GTK drew the underscore literally: `_Directory` in the row, not a D with a line under it.
Two switches are involved, FALSE by default in each case. `GtkLabel`/`GtkButton` take `use-underline`;
the rows take `AdwPreferencesRow:use-underline`, "whether an embedded underline in the title indicates a
mnemonic". The two buttons in the source form already set it (so their mnemonics worked and showed no
underscore); the thirteen rows did not. All thirteen now do.
The row classes that carry the property are not all related -- AdwEntryRow has its own, while AdwSpinRow,
AdwComboRow and AdwSwitchRow get it through AdwActionRow -- so the probe reads it by name on a GObject
(g_object_class_find_property, then g_object_get) rather than casting to one row type; a cast to a
`GtkWidget*` where the type is only forward-declared does not compile at all.
`_Cancel` and `_Connect` both claimed C in the same form, so Alt+C could only reach one of them: that
marker was unreachable, which is worse than absent because it is in the source to be trusted. `_Connect`
becomes `Conn_ect`, freeing C for Cancel.
[prefs-probe] reads the count (4/4) on the real widgets; check_ui validates the property against the GIR
for every object in every .ui file, inherited properties included.
The toolbar button was the panel's only input: `update_side_visibility()` derived the
panel from the button and never the other way, so the button went on saying "shown" in
two cases where the panel was off -- while there were no signals to show, and after
anything else moved the split view's state.
Binding the two together is not the fix. AdwOverlaySplitView writes `show-sidebar`
itself, at startup and when it collapses, with no user involved; a binding pushes that
into the button, the button's handler reads it as the user's wish, and the sidebar then
never comes back when a source connects -- a worse bug than the one reported, and one
that a "was this our own write" flag does not catch either, because the toggle's signal
may fire after the write returns.
So the direction is stated instead of inferred: `show-sidebar` is an output, the button
is the only input, and `App::sidebar_wanted` holds the wish between them. The wish is
written by the toggle's handler alone (guarded while we set the button ourselves), the
no-signals case forces the panel off without touching the wish, and tick() re-asserts
both from the wish when the widget disagrees -- so a hide gesture does not stick either.
[sidebar-probe] now reads the pair (shown vs button) in both states and against a hide
that did not come from the button; shown=1 button=1 with a source, shown=0 button=0
without, and the source reconnecting brings both back is the reading this exists for.
The sidebar's width was a GtkPaned divider position: `window - 940` in pixels. On any window
narrower than 940 px the divider landed past the right edge and the sidebar came up 0 px wide,
reachable only by dragging the divider back.
Every attempt that kept the paned failed for that reason -- deriving the position from the paned's
own width, re-parenting the column, property-form children, code-set size requests. The mechanism was
the fault, so it is gone: the row is an AdwOverlaySplitView, which is what a utility sidebar is in
GNOME, with min-sidebar-width = max-sidebar-width = 320 in pixels. Its width is therefore its own at
any window size, and when there is no room beside the plot it *overlays* the plot (collapsed, set from
the window's width in tick()) instead of being squeezed to nothing.
Two things found on the way, both recorded in the invariants:
- sidebar-width-fraction is a 0..1 fraction of the window whatever sidebar-width-unit says. Setting a
pixel count there is a GObject critical and it falls back to 0.25, which is why the sidebar first
read 560. The width is pinned with min/max instead.
- the window opened at its content minimum (756 px, the plot column plus the sidebar) because the
explicit gtk_window_set_default_size() was dropped when the window moved into the .ui. Restored.
[sidebar-probe] reads both states and is the guard: window=756 sidebar=320 under a 2x scale, which is
the case that used to read 0.
`side_w` is the sidebar column's width, and it must be its own request (320) rather than 0. It turned
a report of "I cannot see the right side panel" into `side_w=0` in one run, which is what a reading is
for.
It also shows the shape of the fault: the width is 320 during the first frames and 0 once the window
settles, while the divider sits at 940 and the plot column ends around 752 -- so the paned is not
giving the sidebar any width, whatever the column asks for.
Four attempts to fix that here were each reverted, because each one left `side_w=0`: placing the
divider from the paned's own width instead of an absolute 940, the property form of the paned's
children, re-parenting the column in code, and a code-set size request on the scroller and the column.
The cause is not one of those, and the next step is to read the paned's own width and the column's
parent chain rather than to guess again.
src/ui/preferences.ui is an AdwPreferencesDialog whose rows are libadwaita's own -- AdwEntryRow,
AdwSpinRow, AdwSwitchRow, AdwComboRow, AdwButtonRow -- instead of a label and a bare GtkEntry in a
GtkBox. There is no Apply button: a row applies as it changes, which is what those widgets are
designed around, and [prefs-probe] reads the settings file back after every change.
The folder chooser is cancellable now, so a picker still open when the dialog closes cannot write
into a row that is gone; the cancellable is also how the probe takes the cancel path without a
mouse.
Two traps cost a run each and are recorded in docs/claude/invariants-gtk-and-chrome.md: an
AdwDialog is not a GtkWindow (it cannot parent a GtkFileDialog, and in floating mode it adds a
native surface to gtk_window_get_toplevels() that is neither a widget nor a window), and a .ui
that is not listed in the GResource is a Gtk-ERROR at runtime rather than a build failure -- which
is exactly what the probe opening every window is for.
GTK4 and libadwaita. It receives one UDP stream through the vendored
udpsclient, buffers it in a large ring, and draws it with the vendored
plotter: a trigger with a pre/post event window, a pause that freezes the
window, cursors, measurements, math channels in a node editor, an event cache,
named configurations, preferences, and an export of the visible window to
.npy/.csv. Waveform files can be opened and analysed in place.
The interface is two threads -- a producer that owns the socket and the GTK
main thread that owns every widget and the GL context -- sharing one model
under one mutex, with samples crossing through lock-free rings.
deps/plotter is a submodule pinned to the commit this tree builds against;
deps/udpsclient is vendored in place. docs/claude/ documents the rules that
cost a defect to learn, and SPECS.md is the requirement document.
Martino Ferrari