1 files changed, 158 insertions, 0 deletions
diff --git a/src/com/jsyn/ports/UnitGatePort.java b/src/com/jsyn/ports/UnitGatePort.java
new file mode 100644
index 0000000..43d5e7f
--- /dev/null
+++ b/src/com/jsyn/ports/UnitGatePort.java
@@ -0,0 +1,158 @@
+/*
+ * Copyright 2009 Phil Burk, Mobileer Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.jsyn.ports;
+
+import com.jsyn.unitgen.UnitGenerator;
+import com.softsynth.shared.time.ScheduledCommand;
+import com.softsynth.shared.time.TimeStamp;
+
+public class UnitGatePort extends UnitInputPort {
+    private boolean autoDisableEnabled = false;
+    private boolean triggered = false;
+    private boolean off = true;
+    private UnitGenerator gatedUnit;
+    public static final double THRESHOLD = 0.01;
+
+    public UnitGatePort(String name) {
+        super(name);
+    }
+
+    public void on() {
+        setOn(true);
+    }
+
+    public void off() {
+        setOn(false);
+    }
+
+    public void off(TimeStamp timeStamp) {
+        setOn(false, timeStamp);
+    }
+
+    public void on(TimeStamp timeStamp) {
+        setOn(true, timeStamp);
+    }
+
+    private void setOn(final boolean on) {
+        queueCommand(new ScheduledCommand() {
+            @Override
+            public void run() {
+                setOnInternal(on);
+            }
+        });
+    }
+
+    private void setOn(final boolean on, TimeStamp timeStamp) {
+        scheduleCommand(timeStamp, new ScheduledCommand() {
+            @Override
+            public void run() {
+                setOnInternal(on);
+            }
+        });
+    }
+
+    private void setOnInternal(boolean on) {
+        if (on) {
+            triggerInternal();
+        }
+        setValueInternal(on ? 1.0 : 0.0);
+    }
+
+    private void triggerInternal() {
+        getGatedUnit().setEnabled(true);
+        triggered = true;
+    }
+
+    public void trigger() {
+        queueCommand(new ScheduledCommand() {
+            @Override
+            public void run() {
+                triggerInternal();
+            }
+        });
+    }
+
+    public void trigger(TimeStamp timeStamp) {
+        scheduleCommand(timeStamp, new ScheduledCommand() {
+            @Override
+            public void run() {
+                triggerInternal();
+            }
+        });
+    }
+
+    /**
+     * This is called by UnitGenerators. It sets the off value that can be tested using isOff().
+     * 
+     * @param i
+     * @return true if triggered by a positive edge.
+     */
+    public boolean checkGate(int i) {
+        double[] inputs = getValues();
+        boolean result = triggered;
+        triggered = false;
+        if (off) {
+            if (inputs[i] >= THRESHOLD) {
+                result = true;
+                off = false;
+            }
+        } else {
+            if (inputs[i] < THRESHOLD) {
+                off = true;
+            }
+        }
+        return result;
+    }
+
+    public boolean isOff() {
+        return off;
+    }
+
+    public boolean isAutoDisableEnabled() {
+        return autoDisableEnabled;
+    }
+
+    /**
+     * Request the containing UnitGenerator be disabled when checkAutoDisabled() is called. This can
+     * be used to reduce CPU load.
+     * 
+     * @param autoDisableEnabled
+     */
+    public void setAutoDisableEnabled(boolean autoDisableEnabled) {
+        this.autoDisableEnabled = autoDisableEnabled;
+    }
+
+    /**
+     * Called by UnitGenerator when an envelope reaches the end of its contour.
+     */
+    public void checkAutoDisable() {
+        if (autoDisableEnabled) {
+            getGatedUnit().setEnabled(false);
+        }
+    }
+
+    private UnitGenerator getGatedUnit() {
+        return (gatedUnit == null) ? getUnitGenerator() : gatedUnit;
+    }
+
+    public void setupAutoDisable(UnitGenerator unit) {
+        gatedUnit = unit;
+        setAutoDisableEnabled(true);
+        // Start off disabled so we don't immediately swamp the CPU.
+        gatedUnit.setEnabled(false);
+    }
+}