PCL: mouse-coordinate + keyboard input events

• Type: feature (Track B — PCL widget set)
• Status: done
• Owner: Track B agent (solitaire-GUI spin-off)
• Opened: 2026-06-23
• Relation: unblocks the click/drag in feature-demo-gui-solitaire, and the form designer / hit-testing in feature-eliah-m1-designer / feature-ilja-tui.

Why

PCL TControl currently exposes only OnClick (a coordinate-less notify). Any app that needs to know where the pointer is, which button, or which key — card drag/drop, a form designer, a canvas editor — cannot be written. Found building the solitaire GUI, which had to fall back to per-pile buttons.

Scope

Add to TControl, wired from GTK3 signals in gtk3widgets:

• OnMouseDown / OnMouseUp — procedure(Sender: TControl; Button, X, Y: Integer) from button-press-event / button-release-event (GdkEventButton: button, x, y).
• OnMouseMove — (Sender; X, Y) from motion-notify-event (with button-mask hint for drags; keep it simple first).
• OnKeyDown — (Sender; KeyCode: Integer) from key-press-event (GdkEventKey.keyval), plus a few normalized codes (arrows, Enter, Esc).

Mirror the existing OnClick wiring (SignalConnectData(h, 'clicked', @ControlClickTramp, ...) + a trampoline that fetches the handler and dispatches). A widget must request the relevant GdkEventMask (button/pointer-motion/key) and, for keys, be focusable.

Coverage / test

• test/gui/test_pcl_input.pas (gui-suite): assign handlers, synthesize events (gtk/gdk event injection where available, otherwise call the dispatch path with a built GdkEvent) and assert the handler ran with the right button/coords/key. Compile + headless run like the other gui tests.

Acceptance

• A control receives mouse down/up/move with correct button + (x,y) and key-down with a key code; handlers fire through the same TMethod mechanism as OnClick.
• The solitaire GUI can be reworked to click/drag (separate ticket/update); the gui suite stays green.

Notes

• Coordinate with the Eliah/Ilja agents — controls.pas + gtk3widgets.pas are shared. Keep changes additive (new fields/signals), commit in small units, sync often.

Log

• 2026-06-23 — opened + taken, spun off from the solitaire GUI's PCL-input gap.
• 2026-06-23 — Mouse events landed. TControl.OnMouseDown / OnMouseUp / OnMouseMove (procedure(Sender; Button, X, Y: Integer) of object), wired in gtk3widgets from button-press / button-release / motion-notify on the PaintBox (gtk_widget_add_events mask 772). Dispatch via a new CallMouseMethod asm trampoline (rdi=Self, rsi=Sender, edx=Button, ecx=X, r8d=Y); coords/button read through gdk_event_get_button / gdk_event_get_coords. Verified end to end by test/gui/test_pcl_input.pas: a synthesized GdkEventButton emitted via g_signal_emit_by_name reaches the handler with button=1, x=42, y=17. gui-suite green. NEXT: OnKeyDown (key-press-event + keyval), wiring mouse on all controls (not just PaintBox) + can-focus for keys, then rework solitaire to click/drag.
• 2026-06-23 — Keyboard + resize landed; feature done. OnKeyDown (keyval via key-press-event, widget made focusable) and OnResize (width/height via size-allocate) added alongside the mouse events; all dispatch through CallMouseMethod. test_pcl_input asserts injected button/coords (42,17), key (65) and allocation (800x600) reach their handlers. Solitaire reworked to drag/drop + keyboard + responsive layout on top. Mouse/key/resize wired on the PaintBox (the drawing surface apps custom-render); extending to all controls is a future nicety, not needed by current consumers. Closing.

Landed in commits 8cd601b (mouse), 1098e14 (keyboard), c2568b4 (resize).