sw: Implement livetime for screens

Also, implement volume screen.

software/webradio.py

@@ -18,7 +18,6 @@ class display(object):
 		self.font_info = ImageFont.truetype('/usr/share/fonts/TTF/DejaVuSans.ttf', 10)
 		self.img = Image.new('1', (self.width, self.height), color = not self.fg)
 		self.d = ImageDraw.Draw(self.img)
-		self.bar_redraw = True
 
 	def render(self):
 		print("render NYI")
@@ -39,10 +38,12 @@ class display_playback(display):
 		self.info = ""
 		self.syms = [];
 		self.title_img = Image.new('1', (0, 0), color = not self.fg)
+		self.bar_redraw = True
 
-	def update_text(self, title):
+	def update_text(self, title, center=False):
 		self.title = title
 
+		font_shift = 5
 		w,h = self.d.textsize(self.title, font=self.font_title)
 		if (w > self.width): # Check the text is short enough to be static
 			self.title += "."
@@ -53,11 +54,17 @@ class display_playback(display):
 			# Prerender
 			fw = w + self.width
 			self.title_img = Image.new('1', (fw, h), color = not self.fg)
-			font_shift = 5
 			ImageDraw.Draw(self.title_img).text((0,-font_shift), self.title, font=self.font_title, fill=self.fg)
 			self.title_img.paste(self.title_img, (w,0))
 			self.title_img = self.title_img.crop((0,0,fw,h-font_shift))
 		else:
+			if (center):
+				x_shift = (self.width - w) / 2
+			else:
+				x_shift = 0;
+			w = self.width
+			self.title_img = Image.new('1', (w, h), color = not self.fg)
+			ImageDraw.Draw(self.title_img).text((x_shift,-font_shift), self.title, font=self.font_title, fill=self.fg)
 			self.title_scroll = 0
 			self.title_scroll_max = -1
 
@@ -105,8 +112,14 @@ class display_manager(object):
 		self.tick = 0
 		self.current_display = None
 
-	def set_display(self, disp):
+	def set_display(self, disp, live=-1):
 		self.current_display = disp
+		self.current_display.live = live
+
+	def display_is_dead(self):
+		if (self.current_display):
+			return (self.current_display.live == 0)
+		return 0
 
 	def render(self):
 		if (self.current_display):
@@ -126,6 +139,8 @@ class display_manager(object):
 				self.current_display.ltick = old_tick
 			self.current_display.animate(self.tick - self.current_display.ltick)
 			self.current_display.ltick = self.tick
+			if (self.current_display.live > 0):
+				self.current_display.live -= ticks
 		# TODO: Consider also animating inactive screens... Might resolve some glitches when updating text while a screen is in the background (or pass `tick` to update funcs)
 
 class radioserv:
@@ -160,11 +175,16 @@ class radioserv:
 				nvol = 0;
 			elif (nvol > 100):
 				nvol = 100
+			self.disp_info.update_text("{}%".format(nvol), True)
+			self.disp_info.update_info("Volume")
+			self.disp_mgr.set_display(self.disp_info, 40)
 			self.mpd.setvol(nvol)
 		#print("Battery: {}".format(rdata[2]))
 
 	async def io_main(self):
 		while True:
+			if self.disp_mgr.display_is_dead():
+				self.disp_mgr.set_display(self.disp_playback)
 			self.disp_mgr.animate(1)
 			self.disp_mgr.render()
 			rdata = self.spi.xfer([100, 101, 102], 50000, 1000)
@@ -243,6 +263,9 @@ class radioserv:
 		self.disp_playback = display_playback()
 		self.disp_playback.update_text("Loading...")
 
+		self.disp_info = display_playback()
+		self.disp_info.update_text("---");
+
 		self.disp_mgr = display_manager()
 		self.disp_mgr.set_display(self.disp_playback)