May as well commit that!

py/hexagram/dial.py

@@ -31,6 +31,19 @@ class Dial(Gauge):
 
         return gradient
 
+    def draw_number(self, cr: cairo.Context, radius: float, value: float, text: str):
+        angle = self.min_angle + ((self.max_angle - self.min_angle) * value) - 1.658;
+
+        cr.set_source_rgb(1, 1, 1)
+        cr.move_to(self.x + radius * self.radius * math.cos(angle),
+                   self.y + radius * self.radius * math.sin(angle))
+
+        cr.save()
+        cr.rotate(angle + 1.658)
+        cr.show_text(text)
+        cr.stroke()
+        cr.restore()
+
     def draw_bg(self, cr: cairo.Context):
         arc = (self.x,
                self.y,

py/hexagram/speedo.py

@@ -1,5 +1,6 @@
 import enum
 import math
+import cairo
 
 from hexagram.cluster import Dial
 
@@ -18,3 +19,13 @@ class Speedo(Dial):
 
         self.units     = units
         self.max_speed = max_speed
+
+    def draw_bg(self, cr: cairo.Context):
+        super().draw_bg(cr)
+
+        cr.select_font_face("Helvetica")
+        cr.set_font_size(self.radius * 0.125)
+        cr.set_source_rgb(1, 1, 1)
+
+        for speed in range(0, int(self.max_speed), 50):
+            self.draw_number(cr, 0.75, speed, str(int(speed)))