display: Support writing single character glyphs using write_glyph()

Add write_glyph() support to hd44780.py.  Update uc1701.py and
st7920.py to support writing single character glyphs via
write_glyph().

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

klippy/extras/display/display.py

@@ -142,12 +142,12 @@ class PrinterLCD:
         # Heaters
         if self.extruder0 is not None:
             info = self.extruder0.get_heater().get_status(eventtime)
-            self.lcd_chip.write_glyph(0, 0, 'nozzle')
+            self.lcd_chip.write_glyph(0, 0, 'extruder')
             self.draw_heater(2, 0, info)
         extruder_count = 1
         if self.extruder1 is not None:
             info = self.extruder1.get_heater().get_status(eventtime)
-            self.lcd_chip.write_glyph(0, 1, 'nozzle')
+            self.lcd_chip.write_glyph(0, 1, 'extruder')
             self.draw_heater(2, 1, info)
             extruder_count = 2
         if self.heater_bed is not None:

klippy/extras/display/hd44780.py

@@ -100,11 +100,18 @@ class HD44780:
             data = data[:20 - min(x, 20)]
         pos = [0, 40, 20, 60][y] + x
         self.text_framebuffer[0][pos:pos+len(data)] = data
+    def write_glyph(self, x, y, glyph_name):
+        char = TextGlyphs.get(glyph_name)
+        if char is not None:
+            # Draw character
+            self.write_text(x, y, char)
+            return 1
+        return 0
     def clear(self):
         self.text_framebuffer[0][:] = ' '*80
 
 HD44780_chars = [
-    # Thermometer
+    # Extruder (a thermometer)
     0b00100,
     0b01010,
     0b01010,
@@ -122,7 +129,7 @@ HD44780_chars = [
     0b11111,
     0b00000,
     0b00000,
-    # Speed factor
+    # Feed rate
     0b11100,
     0b10000,
     0b11000,
@@ -168,3 +175,14 @@ HD44780_chars = [
     0b11111,
     0b00000,
 ]
+
+TextGlyphs = {
+    'right_arrow': '\x7e',
+    'extruder': '\x00',
+    'bed': '\x01',
+    'feedrate': '\x02',
+    'clock': '\x03',
+    'degrees': '\x04',
+    'usb': '\x05',
+    'sd': '\x06',
+}

klippy/extras/display/icons.py

@@ -4,7 +4,7 @@
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 
-nozzle_icon = [
+extruder_icon = [
     0b0000000000000000,
     0b0000000000000000,
     0b0000111111110000,
@@ -138,7 +138,7 @@ feedrate_icon = [
 ]
 
 Icons16x16 = {
-    'nozzle': nozzle_icon,
+    'extruder': extruder_icon,
     'bed': bed_icon, 'bed_heat1': bed_heat1_icon, 'bed_heat2': bed_heat2_icon,
     'fan1': fan1_icon, 'fan2': fan2_icon,
     'feedrate': feedrate_icon,

klippy/extras/display/st7920.py

@@ -12,6 +12,8 @@ BACKGROUND_PRIORITY_CLOCK = 0x7fffffff00000000
 ST7920_CMD_DELAY  = .000020
 ST7920_SYNC_DELAY = .000045
 
+TextGlyphs = { 'right_arrow': '\x1a' }
+
 class ST7920:
     char_right_arrow = '\x1a'
     def __init__(self, config):
@@ -132,12 +134,19 @@ class ST7920:
         if glyph_id is not None and x & 1 == 0:
             # Render cached icon using character generator
             self.write_text(x, y, glyph_id)
-            return
+            return 2
         icon = icons.Icons16x16.get(glyph_name)
         if icon is not None:
             # Draw icon in graphics mode
             for i, bits in enumerate(icon):
                 self.write_graphics(x, y, i, [(bits >> 8) & 0xff, bits & 0xff])
+            return 2
+        char = TextGlyphs.get(glyph_name)
+        if char is not None:
+            # Draw character
+            self.write_text(x, y, char)
+            return 1
+        return 0
     def clear(self):
         self.text_framebuffer[0][:] = ' '*64
         zeros = bytearray(32)

klippy/extras/display/uc1701.py

@@ -9,6 +9,8 @@ import icons, font8x14
 
 BACKGROUND_PRIORITY_CLOCK = 0x7fffffff00000000
 
+TextGlyphs = { 'right_arrow': '\x1a' }
+
 class UC1701:
     char_right_arrow = '\x1a'
     CURRENT_BUF, OLD_BUF = 0, 1
@@ -153,6 +155,13 @@ class UC1701:
             # Draw icon in graphics mode
             for i, bits in enumerate(icon):
                 self.write_graphics(x, y, i, [(bits >> 8) & 0xff, bits & 0xff])
+            return 2
+        char = TextGlyphs.get(glyph_name)
+        if char is not None:
+            # Draw character
+            self.write_text(x, y, char)
+            return 1
+        return 0
     def clear(self):
         zeros = bytearray(128)
         for page in self.vram[self.CURRENT_BUF]: