split realtime timing from sim.step()

BlueSky_pygame.py

@@ -15,7 +15,7 @@ def main():
 
     # Main loop for BlueSky
     while not bs.sim.state == bs.END:
-        bs.sim.step()   # Update sim
+        bs.sim.update()   # Update sim
         bs.scr.update()   # GUI update
 
     bs.sim.quit()

bluesky/network/detached.py

@@ -10,8 +10,8 @@ def __init__(self, *args):
         self.host_id = b''
         self.running = True
 
-    def step(self):
-        ''' Perform one iteration step. Reimplemented in Simulation. '''
+    def update(self):
+        ''' Update timers. '''
         # Process timers
         Timer.update_timers()
 
@@ -28,7 +28,7 @@ def run(self):
         ''' Start the main loop of this node. '''
         while self.running:
             # Perform a simulation step
-            self.step()
+            self.update()
             bs.sim.step()
 
     def connect(self):

bluesky/network/node.py

@@ -19,8 +19,8 @@ def __init__(self, event_port, stream_port):
         self.event_port = event_port
         self.stream_port = stream_port
 
-    def step(self):
-        ''' Perform one iteration step. Reimplemented in Simulation. '''
+    def update(self):
+        ''' Update timers and perform I/O. '''
         # Process timers
         Timer.update_timers()
         # Get new events from the I/O thread
@@ -63,10 +63,10 @@ def run(self):
         ''' Start the main loop of this node. '''
         while self.running:
             # Perform a simulation step
-            self.step()
-            bs.sim.step()
+            self.update()
+            bs.sim.update()
             # Update screen logic
-            bs.scr.step()
+            bs.scr.update()
 
     def addnodes(self, count=1):
         self.send_event(b'ADDNODES', count)

bluesky/simulation/screenio.py

@@ -55,7 +55,7 @@ def __init__(self):
         self.fast_timer.timeout.connect(self.send_aircraft_data)
         self.fast_timer.start(int(1000 / self.acupdate_rate))
 
-    def step(self):
+    def update(self):
         if bs.sim.state == bs.OP:
             self.samplecount += 1
 

bluesky/simulation/simulation.py

@@ -53,24 +53,16 @@ def __init__(self):
         # Keep track of known clients
         self.clients = set()
 
-    def step(self):
-        ''' Perform a simulation timestep. '''
-        # Simulation starts as soon as there is traffic, or pending commands
+    def step(self, dt_increment=0):
+        ''' Perform one simulation timestep.
+        
+            Call this function instead of update if you don't want to run with a fixed
+            real-time rate.
+        '''
         if self.state == bs.INIT:
-            if self.syst < 0.0:
-                self.syst = time.time()
-
+            # Simulation starts as soon as there is traffic, or pending commands
             if bs.traf.ntraf > 0 or len(bs.stack.get_scendata()[0]) > 0:
                 self.op()
-                if self.benchdt > 0.0:
-                    self.fastforward(self.benchdt)
-                    self.bencht = time.time()
-
-        # When running at a fixed rate, or when in hold/init,
-        # increment system time with sysdt and calculate remainder to sleep.
-        remainder = self.syst - time.time()
-        if (not self.ffmode or self.state != bs.OP) and remainder > MINSLEEP:
-            time.sleep(remainder)
 
         # Always update stack
         simstack.process()
@@ -81,15 +73,8 @@ def step(self):
             datalog.update()
             simtime.preupdate()
 
-            # Determine interval towards next timestep
-            if remainder < 0.0 and self.rtmode:
-                # Allow a variable timestep when we are running realtime
-                self.simt, self.simdt = simtime.step(-remainder)
-            else:
-                # Don't accumulate delay when we aren't running realtime
-                if remainder < 0.0:
-                    self.syst -= remainder
-                self.simt, self.simdt = simtime.step()
+            # Determine interval towards next timestep                
+            self.simt, self.simdt = simtime.step(dt_increment)
 
             # Update UTC time
             self.utc += datetime.timedelta(seconds=self.simdt)
@@ -98,6 +83,34 @@ def step(self):
             bs.traf.update()
             simtime.update()
 
+    def update(self):
+        ''' Perform a simulation update. 
+            This involves performing a simulation step, and when running in real-time mode
+            (or a multiple thereof), sleeping an appropriate time. '''
+        if self.state == bs.INIT:
+            if self.syst < 0.0:
+                self.syst = time.time()
+
+            if self.benchdt > 0.0:
+                self.fastforward(self.benchdt)
+                self.bencht = time.time()
+
+        # When running at a fixed rate, or when in hold/init,
+        # increment system time with sysdt and calculate remainder to sleep.
+        remainder = self.syst - time.time()
+        if (not self.ffmode or self.state != bs.OP) and remainder > MINSLEEP:
+            time.sleep(remainder)
+
+        # Perform one simulation timestep
+        if remainder < 0.0 and self.rtmode:
+            # Allow a variable timestep when we are running realtime
+            self.step(-remainder)
+        else:
+            # Don't accumulate delay when we aren't running realtime
+            if remainder < 0:
+                self.syst -= remainder
+            self.step()
+
         # Always update syst
         self.syst += self.simdt / self.dtmult
 
@@ -111,6 +124,7 @@ def step(self):
             else:
                 self.op()
 
+
         # Inform main of our state change
         if self.state != self.prevstate:
             bs.net.send_event(b'STATECHANGE', self.state)
@@ -179,6 +193,7 @@ def realtime(self, flag=None):
 
     def fastforward(self, nsec=None):
         ''' Run in fast-time (for nsec seconds if specified). '''
+        self.state = bs.OP
         self.ffmode = True
         self.ffstop = (self.simt + nsec) if nsec else None