Record FPS samples

TextCanvas.py

@@ -3,6 +3,7 @@
 from .RAIILock import RAIILock
 
 
+from collections import deque
 import math
 import os
 import threading
@@ -20,6 +21,8 @@ class TextCanvas:
 	__DRAW_RESOLUTION = 3
 	__DEFAULT_TEXT_HEIGHT_TO_WIDTH_RATIO = 2.0
 	
+	__MAX_FPS_SAMPLES = 100
+	
 	def __init__(
 		self,
 		output_width=None, output_height=None, text_to_height_width=None,
@@ -62,6 +65,49 @@ class TextCanvas:
 		self.__render_string = ""
 		self.__is_dirty = True
 		self.__last_render_time = time.time()
+		self.__last_get_render_time = time.time()
+		self.__fps_samples = deque(maxlen=self.__MAX_FPS_SAMPLES)
+		
+		self.__conveyor_enabled = False
+		self.__conveyor_thread = None
+		self._start_conveyor()
+	
+	def __exit__(self, exc_type, exc_val, exc_tb):
+		
+		self.shutdown()
+	
+	def shutdown(self):
+		
+		self._stop_conveyor()
+	
+	def _start_conveyor(self, acquire_locks=True):
+		
+		with RAIILock(self.__lock, defer=not acquire_locks):
+			
+			self._stop_conveyor(acquire_locks=False)
+			
+			self.__conveyor_enabled = True
+			self.__conveyor_thread = threading.Thread(target=self._conveyor)
+			self.__conveyor_thread.start()
+		
+	def _stop_conveyor(self, acquire_locks=True):
+		
+		with RAIILock(self.__lock, defer=not acquire_locks):
+			
+			if self.__conveyor_thread:
+				
+				self.__conveyor_enabled = False
+				self.__conveyor_thread.join()
+				self.__conveyor_thread = None
+	
+	def _conveyor(self):
+		
+		# So far simply does maintenance once per second
+		while self.__conveyor_enabled is True:
+			
+			self.__fps_samples.append(0)
+			
+			time.sleep(1)
 	
 	def _update_virtual_ratios(self, acquire_locks=True):
 		
@@ -105,10 +151,35 @@ class TextCanvas:
 		
 		with RAIILock(self.__lock, defer=not acquire_locks):
 			
+			self._record_frame_get(acquire_locks=False)
 			self._update_render_if_dirty(acquire_locks=False)
 			
 			return self.__render_string
 	
+	def _record_frame_get(self, acquire_locks=True):
+		
+		with RAIILock(self.__lock, defer=not acquire_locks):
+			
+			if len(self.__fps_samples) == 0:
+				return
+			
+			self.__fps_samples[0] += 1
+	
+	def get_fps(self, acquire_locks=True):
+		
+		with RAIILock(self.__lock, defer=not acquire_locks):
+			
+			if len(self.__fps_samples) == 0:
+				return 0
+			
+			fps = 0
+			for f in self.__fps_samples:
+				fps += f
+			
+			fps /= len(self.__fps_samples)
+			
+			return fps
+	
 	def print(self, acquire_locks=True):
 		
 		with RAIILock(self.__lock, defer=not acquire_locks):