Juggling things around...

git-svn-id: http://svn.drobilla.net/lad/grauph@13 a436a847-0d15-0410-975c-d299462d15a1

1 files changed, 86 insertions, 0 deletions

diff --git a/src/engine/events/QueuedEvent.h b/src/engine/events/QueuedEvent.h
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+++ b/src/engine/events/QueuedEvent.h
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+/* This file is part of Om.  Copyright (C) 2006 Dave Robillard.
+ * 
+ * Om 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.
+ * 
+ * Om is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef QUEUEDEVENT_H
+#define QUEUEDEVENT_H
+
+#include "Event.h"
+
+namespace Om {
+
+class Responder;
+class QueuedEventSource;
+
+
+/** An Event with a not-time-critical preprocessing stage.
+ *
+ * These events are events that aren't able to be executed immediately by the
+ * Jack thread (because they allocate memory or whatever).  They are pushed
+ * on to the QueuedEventQueue where they are preprocessed then pushed on
+ * to the realtime Event Queue when they are ready.
+ *
+ * Lookups for these events should go in the pre_process() method, since they are
+ * not time critical and shouldn't waste time in the audio thread doing
+ * lookups they can do beforehand.  (This applies for any expensive operation that
+ * could be done before the execute() method).
+ *
+ * \ingroup engine
+ */
+class QueuedEvent : public Event
+{
+public:
+	/** Process this event into a realtime-suitable event.
+	 */
+	virtual void pre_process() {
+		assert(m_pre_processed == false);
+		m_pre_processed = true;
+	}
+
+	virtual void execute(samplecount offset) {
+		assert(m_pre_processed);
+		Event::execute(offset);
+	}
+
+	virtual void post_process() {}
+
+	/** If this event blocks the prepare phase of other slow events */
+	bool is_blocking() { return m_blocking; }
+
+	bool is_prepared() { return m_pre_processed; }
+	
+protected:
+	// Prevent copies
+	QueuedEvent(const QueuedEvent& copy);
+	QueuedEvent& operator=(const QueuedEvent&);
+	
+	QueuedEvent(CountedPtr<Responder> responder, bool blocking = false, QueuedEventSource* source=NULL)
+	: Event(responder), m_pre_processed(false), m_blocking(blocking), m_source(source)
+	{}
+	
+	// NULL event base (for internal events)
+	QueuedEvent()
+	: Event(), m_pre_processed(false), m_blocking(false), m_source(NULL)
+	{}
+
+	bool               m_pre_processed;
+	bool               m_blocking;
+	QueuedEventSource* m_source;
+};
+
+
+} // namespace Om
+
+#endif // QUEUEDEVENT_H