Merge pull request #198 from b-ma/feature/zero-delay

Enable sub quantum delay

src/context/concrete_base.rs

@@ -203,6 +203,17 @@ impl ConcreteBaseAudioContext {
         }
     }
 
+    /// Inform render thread that this node can act as a cycle breaker
+    #[doc(hidden)]
+    pub fn mark_cycle_breaker(&self, reg: &AudioContextRegistration) {
+        let id = reg.id().0;
+        let message = ControlMessage::MarkCycleBreaker { id };
+
+        // Sending the message will fail when the render thread has already shut down.
+        // This is fine
+        let _r = self.inner.render_channel.send(message);
+    }
+
     /// `ChannelConfig` of the `AudioDestinationNode`
     pub(super) fn destination_channel_config(&self) -> ChannelConfig {
         self.inner.destination_channel_config.clone()

src/message.rs

@@ -26,17 +26,28 @@ pub(crate) enum ControlMessage {
     },
 
     /// Clear the connection between two given nodes in the audio graph
-    DisconnectNode { from: u64, to: u64 },
+    DisconnectNode {
+        from: u64,
+        to: u64,
+    },
 
     /// Disconnect this node from the audio graph (drop all its connections)
-    DisconnectAll { from: u64 },
+    DisconnectAll {
+        from: u64,
+    },
 
     /// Notify the render thread this node is dropped in the control thread
-    FreeWhenFinished { id: u64 },
+    FreeWhenFinished {
+        id: u64,
+    },
 
     /// Pass an AudioParam AutomationEvent to the relevant node
     AudioParamEvent {
         to: Sender<AudioParamEvent>,
         event: AudioParamEvent,
     },
+
+    MarkCycleBreaker {
+        id: u64,
+    },
 }

src/node/constant_source.rs

@@ -162,11 +162,6 @@ impl AudioProcessor for ConstantSourceRenderer {
             return true;
         }
 
-        if stop_time < scope.current_time {
-            output.make_silent();
-            return false;
-        }
-
         output.force_mono();
 
         let offset_values = params.get(&self.offset);
@@ -186,7 +181,8 @@ impl AudioProcessor for ConstantSourceRenderer {
             current_time += dt;
         }
 
-        true
+        // tail_time false when output has ended this quantum
+        stop_time >= next_block_time
     }
 }