display: Support requesting a screen redraw on a menu key press

Add a request_redraw() method and call it when a key menu event
occurs.  Limit these proactive screen redraws to no more than 4 per
second.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 16 insertions, 2 deletions

diff --git a/klippy/extras/display/display.py b/klippy/extras/display/display.py
index 11f60a57..8e47e5a1 100644
--- a/klippy/extras/display/display.py
+++ b/klippy/extras/display/display.py
@@ -100,9 +100,12 @@ class PrinterLCD:
         self.show_data_group = self.display_data_groups.get(dgroup)
         if self.show_data_group is None:
             raise config.error("Unknown display_data group '%s'" % (dgroup,))
+        # Screen updating
         self.printer.register_event_handler("klippy:ready", self.handle_ready)
         self.screen_update_timer = self.reactor.register_timer(
             self.screen_update_event)
+        self.redraw_request_pending = False
+        self.redraw_time = 0.
         # Register g-code commands
         gcode = self.printer.lookup_object("gcode")
         gcode.register_mux_command('SET_DISPLAY_GROUP', 'DISPLAY', name,
@@ -111,6 +114,8 @@ class PrinterLCD:
         if name == 'display':
             gcode.register_mux_command('SET_DISPLAY_GROUP', 'DISPLAY', None,
                                        self.cmd_SET_DISPLAY_GROUP)
+    def get_dimensions(self):
+        return self.lcd_chip.get_dimensions()
     # Configurable display
     def _parse_glyph(self, config, glyph_name, data, width, height):
         glyph_data = []
@@ -184,19 +189,28 @@ class PrinterLCD:
         self.reactor.update_timer(self.screen_update_timer, self.reactor.NOW)
     # Screen updating
     def screen_update_event(self, eventtime):
+        if self.redraw_request_pending:
+            self.redraw_request_pending = False
+            self.redraw_time = eventtime + 0.250
+        self.lcd_chip.clear()
         # update menu component
         if self.menu is not None:
             ret = self.menu.screen_update_event(eventtime)
             if ret:
-                return ret
+                self.lcd_chip.flush()
+                return eventtime + .500
         # Update normal display
-        self.lcd_chip.clear()
         try:
             self.show_data_group.show(self, self.display_templates, eventtime)
         except:
             logging.exception("Error during display screen update")
         self.lcd_chip.flush()
         return eventtime + .500
+    def request_redraw(self):
+        if self.redraw_request_pending:
+            return
+        self.redraw_request_pending = True
+        self.reactor.update_timer(self.screen_update_timer, self.redraw_time)
     def draw_text(self, row, col, mixed_text, eventtime):
         pos = col
         for i, text in enumerate(mixed_text.split('~')):