1 files changed, 85 insertions, 0 deletions
diff --git a/render.py b/render.py
new file mode 100644
index 0000000..833b5f5
--- /dev/null
+++ b/render.py
@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+
+import queue
+import time
+import threading
+
+from .audio import DefaultAudioPlayer, AudioPlayer
+from .output import LightingOutput
+from .workspace import SHOW, CHASER, Advanceable 
+
+class FunctionQueue:
+    def after(self, t: float, f: callable):
+        """Run the given function after t milliseconds."""
+        self.queue.put((time.monotonic() + t/1000, f))
+
+    def start(self):
+        """Run until the queue is empty."""
+        while not self.queue.empty():
+            t, f = self.queue.get()
+            time.sleep(max(0, time.monotonic() - t))
+            f()
+
+    def __init__(self):
+        self.queue = queue.SimpleQueue()
+
+class Renderer:
+    """Basic renderer for functions.
+
+    Supports live-rendering Chasers and Shows.
+
+    Instances of this class are NOT thread-safe, with the exception of the advance() method, 
+    which may be called from other threads.
+    """
+    def start(self):
+        if self.start_time != -1:
+            raise ValueError("Already running")
+        self.f.after(0, self.render_step)
+        self.f.start()
+        self.nx = None
+        self.data = None
+        self.vals = {}
+
+    def render_step(self):
+        """Output the current step and render the next one."""
+        if self.nx not in (None, -1):
+            self.fq.after((max(self.minnx, self.nx), self.render_step))
+        elif self.nx is None:
+            self.start_time = time.monotonic()
+
+        self.lo.set_values(tuple(self.values.items()))
+
+        with self.data_lock:
+            t = 1000*(int((time.monotonic() - self.start_time)/1000 + 1) + self.nx)
+            vals, acues, self.nx, self.data = self.f.render(t)
+            for c, v in vals:
+                self.values[c] = v
+
+    def advance(self):
+        """Advance the function, if possible.
+
+        It is not an error to call this function when dealing with non-Advanceable toplevel 
+        functions; this will just do nothing.
+        """
+        with self.data_lock:
+            if self.start_time == -1:
+                raise ValueError("Cannot advance a function that has not been started!")
+            if issubclass(type(self.f), Advanceable):
+                t = 1000*int(self.monotonic() - self.start_time)
+                self.data = self.f.advance(self.data, time.monotonic() - self.start_time)
+                *_, self.data = self.f.render(t)
+
+    def __init__(self, f, lo:LightingOutput, ao: AudioPlayer=DefaultAudioPlayer, minnx=-1):
+        if f.type not in (SHOW, CHASER):
+            raise ValueError("Only Shows and Chasers may be used as toplevel functions")
+        self.start_time = -1
+        self.f = f
+        self.fq = FunctionQueue()
+        self.minnx = minnx
+        self.nx = None
+        self.data = None
+        self.data_lock = threading.Lock() 
+        self.values = {c: 0 for c in self.f.scope}
+        self.lo = lo
+        self.ao = ao
+        self.aplayers = {}