Link various screens accessible from the bridge

This kind of linking is starting to creak...

internal/ui/buttons.go

@@ -11,7 +11,9 @@ func init() {
 	registerBuilder(menus.TypeSimpleButton, registerSimpleButton)
 	registerBuilder(menus.TypeInvokeButton, registerInvokeButton)
 	registerBuilder(menus.TypeMainButton, registerMainButton)
-	registerBuilder(menus.TypeDoorHotspot, registerDebug("Unimplemented DoorHotspot", nil))
+	registerBuilder(menus.TypeDoorHotspot, registerDoorHotspot)
+	registerBuilder(menus.TypeDoorHotspot2, registerDoorHotspot)
+	registerBuilder(menus.TypeDoorHotspot3, registerDoorHotspot)
 }
 
 // A button without hover animation
@@ -79,6 +81,29 @@ func registerMainButton(d *Driver, r *menus.Record) error {
 	return nil
 }
 
+func registerDoorHotspot(d *Driver, r *menus.Record) error {
+	sprites, err := d.menu.Sprites(r.Share, 2) // base, pressed
+	if err != nil {
+		return err
+	}
+
+	btn := &button{
+		path:      r.Path(),
+		baseSpr:   sprites[0],
+		clickSpr:  sprites[1],
+		frozenSpr: sprites[0], // No disabled sprite
+		hoverImpl: hoverImpl{text: r.Text},
+	}
+
+	d.clickables = append(d.clickables, btn)
+	d.freezables = append(d.freezables, btn)
+	d.hoverables = append(d.hoverables, btn)
+	d.paintables = append(d.paintables, btn)
+
+	return nil
+
+}
+
 func registerButton(d *Driver, r *menus.Record, spriteId int) error {
 	sprites, err := d.menu.Sprites(spriteId, 3) // base, pressed, disabled
 	if err != nil {