Preliminary MIDI plugin support.

git-svn-id: svn://localhost/ardour2/branches/3.0@5036 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 82 insertions, 0 deletions

diff --git a/libs/ardour/ardour/chan_mapping.h b/libs/ardour/ardour/chan_mapping.h
new file mode 100644
index 0000000000..1dae20e34a
--- /dev/null
+++ b/libs/ardour/ardour/chan_mapping.h
@@ -0,0 +1,82 @@
+/*
+    Copyright (C) 2009 Paul Davis 
+	Author: Dave Robillard
+
+    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.
+
+    This program 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 more 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef __ardour_chan_mapping_h__
+#define __ardour_chan_mapping_h__
+
+#include <map>
+#include <cassert>
+#include <ostream>
+#include <utility>
+
+#include "ardour/data_type.h"
+
+namespace ARDOUR {
+
+
+/** A mapping from one set of channels to another
+ * (e.g. how to 'connect' two BufferSets).
+ */
+class ChanMapping {
+public:
+	ChanMapping() {}
+	ChanMapping(ChanCount identity) {
+		for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
+			for (size_t i = 0; i <= identity.get(*t); ++i)
+				set(*t, i, i);
+		}
+	}
+
+	uint32_t get(DataType t, uint32_t from) {
+		Mappings::iterator tm = _mappings.find(t);
+		assert(tm != _mappings.end());
+		TypeMapping::iterator m = tm->second.find(from);
+		assert(m != tm->second.end());
+		return m->second;
+	}
+	
+	void set(DataType t, uint32_t from, uint32_t to) {
+		Mappings::iterator tm = _mappings.find(t);
+		if (tm == _mappings.end()) {
+			tm = _mappings.insert(std::make_pair(t, TypeMapping())).first;
+		}
+		tm->second.insert(std::make_pair(from, to));
+	}
+
+	/** Increase the 'to' field of every mapping for type @a t by @a delta */
+	void offset(DataType t, uint32_t delta) {
+		Mappings::iterator tm = _mappings.find(t);
+		if (tm != _mappings.end()) {
+			for (TypeMapping::iterator m = tm->second.begin(); m != tm->second.end(); ++m) {
+				m->second += delta;
+			}
+		}
+	}
+
+private:
+	typedef std::map<uint32_t, uint32_t>    TypeMapping;
+	typedef std::map<DataType, TypeMapping> Mappings;
+	
+	Mappings _mappings;
+};
+
+} // namespace ARDOUR
+
+#endif // __ardour_chan_mapping_h__
+