initial volley of work for AudioPlaylistSource, the basic prototype for sources-that-are-nested

git-svn-id: svn://localhost/ardour2/branches/3.0@9507 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 250 insertions, 0 deletions

diff --git a/libs/ardour/audio_playlist_source.cc b/libs/ardour/audio_playlist_source.cc
new file mode 100644
index 0000000000..568b72129d
--- /dev/null
+++ b/libs/ardour/audio_playlist_source.cc
@@ -0,0 +1,250 @@
+/*
+    Copyright (C) 2011 Paul Davis
+
+    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.
+*/
+
+#ifdef WAF_BUILD
+#include "libardour-config.h"
+#endif
+
+#include <vector>
+#include <cstdio>
+
+#include <glibmm/fileutils.h>
+
+#include "pbd/error.h"
+#include "pbd/convert.h"
+#include "pbd/enumwriter.h"
+
+#include "ardour/audioplaylist.h"
+#include "ardour/audio_playlist_source.h"
+#include "ardour/audioregion.h"
+#include "ardour/debug.h"
+#include "ardour/session.h"
+#include "ardour/session_directory.h"
+#include "ardour/session_playlists.h"
+#include "ardour/source_factory.h"
+
+#include "i18n.h"
+
+using namespace std;
+using namespace ARDOUR;
+using namespace PBD;
+
+AudioPlaylistSource::AudioPlaylistSource (Session& s, const std::string& name, boost::shared_ptr<AudioPlaylist> p, 
+					  uint32_t chn, frameoffset_t begin, framecnt_t len, bool copy, Source::Flag flags)
+	: Source (s, DataType::AUDIO, name)
+	, AudioSource (s, name)
+	, _playlist_channel (chn)
+{
+	/* PlaylistSources are never writable, renameable, removable or destructive */
+	_flags = Flag (_flags & ~(Writable|CanRename|Removable|RemovableIfEmpty|RemoveAtDestroy|Destructive));
+
+	if (!copy) {
+		_playlist = p;
+		_playlist_offset = begin;
+		_playlist_length = len;
+	} else {
+		_playlist.reset (new AudioPlaylist (p, begin, len, "XXXNAMEXXX", true));
+		_playlist_offset = 0;
+		_playlist_length = len;
+	}
+
+	_peak_path = tempnam (_session.session_directory().peak_path().to_string().c_str(), "apspk");
+}
+
+AudioPlaylistSource::AudioPlaylistSource (Session& s, const XMLNode& node)
+	: Source (s, DataType::AUDIO, "toBeRenamed")
+	, AudioSource (s, node)
+{
+	/* PlaylistSources are never writable, renameable, removable or destructive */
+	_flags = Flag (_flags & ~(Writable|CanRename|Removable|RemovableIfEmpty|RemoveAtDestroy|Destructive));
+	
+	set_state (node, 3000);
+}
+
+AudioPlaylistSource::~AudioPlaylistSource ()
+{
+}
+
+XMLNode&
+AudioPlaylistSource::get_state ()
+{
+	XMLNode& node (AudioSource::get_state ());
+	char buf[64];
+	snprintf (buf, sizeof (buf), "%" PRIi64, _playlist_offset);
+	node.add_property ("offset", buf);
+	snprintf (buf, sizeof (buf), "%" PRIu64, _playlist_length);
+	node.add_property ("length", buf);
+	snprintf (buf, sizeof (buf), "%" PRIu32, _playlist_channel);
+	node.add_property ("channel", buf);
+	node.add_property ("name", name());
+	node.add_property ("peak-path", _peak_path);
+
+	return node;
+}
+
+int
+AudioPlaylistSource::set_state (const XMLNode& node, int /* version */) 
+{
+	/* get playlist ID */
+
+	const XMLProperty *prop = node.property (X_("playlist"));
+
+	if (!prop) {
+		throw failed_constructor ();
+	}
+
+	PBD::ID id (prop->value());
+
+	/* get playlist */
+
+	boost::shared_ptr<Playlist> p = _session.playlists->by_id (id);
+
+	if (!p) {
+		throw failed_constructor ();
+	}
+
+	/* other properties */
+
+	if ((prop = node.property (X_("name"))) == 0) {
+		throw failed_constructor ();
+	}
+	
+	set_name (prop->value());
+
+	if ((prop = node.property (X_("offset"))) == 0) {
+		throw failed_constructor ();
+	}
+	sscanf (prop->value().c_str(), "%" PRIi64, &_playlist_offset);
+
+	if ((prop = node.property (X_("length"))) == 0) {
+		throw failed_constructor ();
+	}
+
+	sscanf (prop->value().c_str(), "%" PRIu64, &_playlist_length);
+
+	if ((prop = node.property (X_("channel"))) == 0) {
+		throw failed_constructor ();
+	}
+
+	sscanf (prop->value().c_str(), "%" PRIu32, &_playlist_channel);
+
+	if ((prop = node.property (X_("peak-path"))) == 0) {
+		throw failed_constructor ();
+	}
+
+	_peak_path = prop->value ();
+
+	return 0;
+}
+
+framecnt_t 
+AudioPlaylistSource::read_unlocked (Sample* dst, framepos_t start, framecnt_t cnt) const
+{
+	framecnt_t to_read;
+	framecnt_t to_zero;
+	pair<framepos_t,framepos_t> extent = _playlist->get_extent();
+
+	/* we must be careful not to read beyond the end of our "section" of
+	 * the playlist, because otherwise we may read data that exists, but
+	 * is not supposed be part of our data.
+	 */
+
+	if (cnt > _playlist_length - start) {
+		to_read = _playlist_length - start;
+		to_zero = cnt - to_read;
+	} else {
+		to_read = cnt;
+		to_zero = 0;
+	}
+
+	_playlist->read (dst, 0, 0, start+_playlist_offset, to_read, _playlist_channel);
+	
+	if (to_zero) {
+		memset (dst+to_read, 0, sizeof (Sample) * to_zero);
+	}
+
+	return cnt;
+}
+
+framecnt_t 
+AudioPlaylistSource::write_unlocked (Sample *src, framecnt_t cnt) 
+{
+	fatal << string_compose (_("programming error: %1"), "AudioPlaylistSource::write() called - should be impossible") << endmsg;
+	/*NOTREACHED*/
+	return 0;
+}
+
+bool
+AudioPlaylistSource::empty () const
+{
+	return !_playlist || _playlist->empty();
+}
+
+uint32_t
+AudioPlaylistSource::n_channels () const
+{
+	/* use just the first region to decide */
+
+	if (empty()) {
+		return 1;
+	}
+
+	boost::shared_ptr<Region> r = _playlist->region_list().front ();
+	boost::shared_ptr<AudioRegion> ar = boost::dynamic_pointer_cast<AudioRegion> (r);
+
+	return ar->audio_source()->n_channels ();
+}
+
+float
+AudioPlaylistSource::sample_rate () const
+{
+	/* use just the first region to decide */
+
+	if (empty()) {
+		_session.frame_rate ();
+	}
+
+	boost::shared_ptr<Region> r = _playlist->region_list().front ();
+	boost::shared_ptr<AudioRegion> ar = boost::dynamic_pointer_cast<AudioRegion> (r);
+
+	return ar->audio_source()->sample_rate ();
+}
+
+int
+AudioPlaylistSource::setup_peakfile ()
+{
+	/* the peak data is setup once and once only 
+	 */
+
+	if (!Glib::file_test (_peak_path, Glib::FILE_TEST_EXISTS)) {
+		/* the 2nd argument here will be passed
+		   in to ::peak_path, and is irrelevant
+		   since our peak file path is fixed and
+		   not dependent on anything.
+		*/
+		
+		return initialize_peakfile (true, string());
+	} 
+	return 0;
+}
+
+string
+AudioPlaylistSource::peak_path (string /*audio_path*/)
+{
+	return _peak_path;
+}