Be less dumb calculating angles

py/hexagram/dial.py

@@ -34,9 +34,16 @@ class Dial(Gauge):
 
         return gradient
 
+    def angle(self, value: float):
+        adj     = value - self.min_value
+        adj_max = self.max_value - self.min_value
+
+        return self.min_angle + \
+            (self.max_angle - self.min_angle) * (adj / adj_max) \
+           - self.ANGLE_OFFSET
+
     def draw_number(self, cr: cairo.Context, radius: float, value: float, text: str):
-        scale = value / self.max_value
+        angle = self.angle(value)
-        angle = self.min_angle + ((self.max_angle - self.min_angle) * scale) - self.ANGLE_OFFSET
 
         cr.move_to(self.x + radius * self.radius * math.cos(angle) - 20,
                    self.y + radius * self.radius * math.sin(angle))
@@ -45,11 +52,7 @@ class Dial(Gauge):
         cr.stroke()
 
     def draw_mark(self, cr: cairo.Context, min_radius: float, max_radius: float, value: float):
-        adj     = value - self.min_value
+        angle = self.angle(value)
-        adj_max = self.max_value - self.min_value
-
-        angle = self.min_angle + \
-            ((self.max_angle - self.min_angle) * (adj / adj_max)) - self.ANGLE_OFFSET
 
         cr.move_to(self.x + (min_radius * self.radius) * math.cos(angle),
                    self.y + (min_radius * self.radius) * math.sin(angle))
@@ -60,12 +63,7 @@ class Dial(Gauge):
         cr.stroke()
 
     def draw_needle(self, cr: cairo.Context, min_radius: float, max_radius: float, value: float):
-        adj     = value - self.min_value
+        angle = self.angle(value)
-        adj_max = self.max_value - self.min_value
-
-        angle = self.min_angle + \
-            ((self.max_angle - self.min_angle) * (adj / adj_max)) \
-            - self.ANGLE_OFFSET
 
         cr.set_source_rgba(1, 0.4, 1, 0.75)
         cr.set_line_width(8)
@@ -106,26 +104,33 @@ class Dial(Gauge):
         self.draw_needle(cr, 0.5, 0.89, self.value)
 
 class BottomDial(Dial):
-    def draw_mark(self, cr: cairo.Context, min_radius: float, max_radius: float, value: float):
+    MIN_ANGLE = 144.0 * (math.pi / 180.0)
-        adj     = value - self.min_value
+    MAX_ANGLE = 216.0 * (math.pi / 180.0)
-        adj_max = self.max_value - self.min_value
 
-        angle = self.min_angle + \
+    def angle(self, value: float):
-            ((self.max_angle - self.min_angle) * (adj / adj_max)) - self.ANGLE_OFFSET
+        return super().angle((self.max_value - value) + self.min_value)
 
-        cr.move_to(self.x + (min_radius * self.radius) * math.cos(angle),
+    def draw_value(self, cr: cairo.Context, radius: float, value: float, text: str, x_offset: float=0.0, y_offset: float=0.0):
-                   self.y + (min_radius * self.radius) * math.sin(angle))
+        angle = self.angle(value)
 
-        cr.line_to(self.x + (max_radius * self.radius) * math.cos(angle),
+        cr.move_to(self.x + radius * self.radius * math.cos(angle) + x_offset,
-                   self.y + (max_radius * self.radius) * math.sin(angle))
+                   self.y + radius * self.radius * math.sin(angle) + y_offset)
 
+        cr.show_text(text)
+        cr.stroke()
+
+    def draw_bg(self, cr: cairo.Context):
+        cr.set_line_width(24)
+        cr.set_source_rgb(0.2, 0.2, 0.2)
+        cr.arc(self.x,
+               self.y,
+               self.radius - 36,
+               self.MIN_ANGLE - self.ANGLE_OFFSET,
+               self.MAX_ANGLE - self.ANGLE_OFFSET + 4 * (math.pi / 180.0))
         cr.stroke()
 
     def draw_fg(self, cr: cairo.Context):
         min_radius = 0.8
         max_radius = 0.9
 
-        adj     = self.value - self.min_value
+        self.draw_needle(cr, min_radius, max_radius, self.value)
-        adj_max = self.max_value - self.min_value
-
-        self.draw_needle(cr, min_radius, max_radius, adj_max - adj)

py/hexagram/fuel.py

@@ -5,9 +5,6 @@ import cairo
 from hexagram.dial import BottomDial
 
 class FuelGauge(BottomDial):
-    MIN_ANGLE = 144.0 * (math.pi / 180.0)
-    MAX_ANGLE = 216.0 * (math.pi / 180.0)
-
     MIN_VALUE =  0
     MAX_VALUE = 15
 
@@ -22,25 +19,8 @@ class FuelGauge(BottomDial):
 
         self.value = 0
 
-    def draw_value(self, cr: cairo.Context, radius: float, value: float, text: str, x_offset: float):
-        scale = (self.max_value - value) / self.max_value
-        angle = self.min_angle + ((self.max_angle - self.min_angle) * scale) - self.ANGLE_OFFSET
-
-        cr.move_to(self.x + radius * self.radius * math.cos(angle) + x_offset,
-                   self.y + radius * self.radius * math.sin(angle))
-
-        cr.show_text(text)
-        cr.stroke()
-
     def draw_bg(self, cr: cairo.Context):
-        cr.set_line_width(24)
+        super().draw_bg(cr)
-        cr.set_source_rgb(0.2, 0.2, 0.2)
-        cr.arc(self.x,
-               self.y,
-               self.radius - 36,
-               self.MIN_ANGLE - self.ANGLE_OFFSET - 4 * (math.pi / 180.0),
-               self.MAX_ANGLE - self.ANGLE_OFFSET + 4 * (math.pi / 180.0))
-        cr.stroke()
 
         cr.select_font_face(self.FONT_FACE,
                             cairo.FontSlant.NORMAL,
@@ -67,4 +47,4 @@ class FuelGauge(BottomDial):
                 min_radius = 0.82
                 cr.set_source_rgb(1, 1, 1)
 
-            self.draw_mark(cr, min_radius, 0.87, self.max_value - level)
+            self.draw_mark(cr, min_radius, 0.87, level)

py/hexagram/thermo.py

@@ -4,9 +4,6 @@ import cairo
 
 from hexagram.dial import BottomDial
 
-    MIN_ANGLE = 144.0 * (math.pi / 180.0)
-    MAX_ANGLE = 216.0 * (math.pi / 180.0)
-
 class Thermometer(BottomDial):
     MIN_VALUE  =  85
     MAX_VALUE  = 110
@@ -21,31 +18,8 @@ class Thermometer(BottomDial):
                          self.MIN_VALUE,
                          self.MAX_VALUE)
 
-    def draw_needle(self, cr: cairo.Context, min_radius: float, max_radius: float, value: float):
-        super().draw_needle(cr, min_radius, max_radius, self.max_value - value)
-
-    def draw_value(self, cr: cairo.Context, radius: float, value: float, text: str, x_offset: float, y_offset: float):
-        adj     = value - self.min_value
-        adj_max = self.max_value - self.min_value
-
-        scale = adj / adj_max
-        angle = self.min_angle + ((self.max_angle - self.min_angle) * scale) - self.ANGLE_OFFSET
-
-        cr.move_to(self.x + radius * self.radius * math.cos(angle) + x_offset,
-                   self.y + radius * self.radius * math.sin(angle) + y_offset)
-
-        cr.show_text(text)
-        cr.stroke()
-
     def draw_bg(self, cr: cairo.Context):
-        cr.set_line_width(24)
+        super().draw_bg(cr)
-        cr.set_source_rgb(0.2, 0.2, 0.2)
-        cr.arc(self.x,
-               self.y,
-               self.radius - 36,
-               self.MIN_ANGLE - self.ANGLE_OFFSET,
-               self.MAX_ANGLE - self.ANGLE_OFFSET + 4 * (math.pi / 180.0))
-        cr.stroke()
 
         cr.select_font_face(self.FONT_FACE,
                             cairo.FontSlant.NORMAL,
@@ -54,17 +28,24 @@ class Thermometer(BottomDial):
         cr.set_font_size(self.radius * 0.1)
 
         cr.set_source_rgb(1, 1, 1)
-        self.draw_value(cr, 0.78, self.min_value, "C", -25, 0)
+        #self.draw_value(cr, 0.78, self.min_value, "C", -25, 0)
+        self.draw_value(cr, 0.78, self.min_value, "C")
 
         cr.set_source_rgb(1, 0, 0)
-        self.draw_value(cr, 0.75, self.max_value, "H", -5, 0)
+        #self.draw_value(cr, 0.75, self.max_value, "H", -5, 0)
+        self.draw_value(cr, 0.75, self.max_value, "H")
 
         cr.set_line_width(6.0)
 
-        for level in range(self.min_value, self.max_value, math.ceil((self.max_value - self.min_value ) / 9)):
+        level = self.min_value
+        incr  = (self.max_value - self.min_value) / 9
+
+        while level <= self.max_value:
             if level >= self.WARN_VALUE:
                 cr.set_source_rgb(0.8, 0, 0)
             else:
                 cr.set_source_rgb(1, 1, 1)
 
             self.draw_mark(cr, 0.83, 0.87, level)
+
+            level += incr