1 files changed, 67 insertions, 0 deletions
diff --git a/src/sound/ExternalTransport.h b/src/sound/ExternalTransport.h
new file mode 100644
index 0000000..f40a5a2
--- /dev/null
+++ b/src/sound/ExternalTransport.h
@@ -0,0 +1,67 @@
+// -*- c-basic-offset: 4 -*-
+/*
+    Rosegarden
+    A sequencer and musical notation editor.
+
+    This program is Copyright 2000-2008
+        Guillaume Laurent   <glaurent@telegraph-road.org>,
+        Chris Cannam        <cannam@all-day-breakfast.com>,
+        Richard Bown        <bownie@bownie.com>
+
+    The moral right of the authors to claim authorship of this work
+    has been asserted.
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#ifndef _EXTERNAL_TRANSPORT_H_
+#define _EXTERNAL_TRANSPORT_H_
+
+namespace Rosegarden {
+
+/**
+ * Simple interface that we can pass to low-level audio code and on
+ * which it can call back when something external requests a transport
+ * change.  The callback is asynchronous, and there's a method for the
+ * low-level code to use to find out whether its request has finished
+ * synchronising yet.
+ *
+ * (Each of the transportXX functions returns a token which can then
+ * be passed to isTransportSyncComplete.)
+ */
+
+class ExternalTransport
+{
+public:
+    typedef unsigned long TransportToken;
+
+    enum TransportRequest {
+        TransportNoChange,
+        TransportStop,
+        TransportStart,
+        TransportPlay,
+        TransportRecord,
+        TransportJumpToTime, // time arg required
+        TransportStartAtTime, // time arg required
+        TransportStopAtTime // time arg required
+    };
+
+    virtual TransportToken transportChange(TransportRequest) = 0;
+    virtual TransportToken transportJump(TransportRequest, RealTime) = 0;
+
+    virtual bool isTransportSyncComplete(TransportToken token) = 0;
+
+    // The value returned here is a constant (within the context of a
+    // particular ExternalTransport object) that is guaranteed never
+    // to be returned by any of the transport request methods.
+    virtual TransportToken getInvalidTransportToken() const = 0;
+};
+
+}
+
+#endif
+