Add English localization and MIT-licensed public release documentation

tools/capture_screenshots.py

@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+"""Capture the actual GTK application with fictional demo data, without USB access."""
+import sys
+from pathlib import Path
+sys.path.insert(0, str(Path(__file__).resolve().parents[1]))
+from btd700.app import Application
+from gi.repository import GLib, Gtk
+
+output = Path(__file__).resolve().parents[1] / 'docs/screenshots'
+output.mkdir(parents=True, exist_ok=True)
+app = Application(demo=True, language='en')
+phase = 0
+attempts = 0
+success = False
+
+
+def capture(name):
+    window = app.window
+    snapshot = Gtk.Snapshot.new()
+    Gtk.WidgetPaintable.new(window).snapshot(snapshot, window.get_width(), window.get_height())
+    node = snapshot.to_node()
+    if node is None:
+        return False
+    texture = window.get_renderer().render_texture(node, None)
+    if not texture.save_to_png(str(output / name)):
+        raise RuntimeError('Could not save screenshot')
+    print(f'{name}: {window.get_width()} × {window.get_height()}', flush=True)
+    return True
+
+
+def tick():
+    global phase, attempts, success
+    attempts += 1
+    try:
+        if attempts > 40:
+            raise TimeoutError('Screenshot window did not become ready')
+        if not app.status or app.busy:
+            return True
+        if phase == 0:
+            app.window.set_default_size(620, 880)
+            phase = 1
+        elif phase == 1:
+            if capture('main-window.png'):
+                adjustment = app.scroll.get_vadjustment()
+                adjustment.set_value(adjustment.get_upper() - adjustment.get_page_size())
+                phase = 2
+        elif phase == 2:
+            if capture('auracast-settings.png'):
+                success = True
+                app.quit()
+                return False
+    except Exception as exc:
+        print(f'Capture failed: {exc}', file=sys.stderr)
+        app.quit()
+        return False
+    return True
+
+GLib.timeout_add(500, tick)
+app.run(['btd700-screenshots'])
+raise SystemExit(0 if success else 1)