diff options
| author | Robin Gareus <robin@gareus.org> | 2020-05-09 23:42:26 +0200 |
|---|---|---|
| committer | Robin Gareus <robin@gareus.org> | 2020-05-09 23:43:04 +0200 |
| commit | 52ae134efb055cfad701b7039df1c7544e47d011 (patch) | |
| tree | 9cbe94f6e7e73b1713486881151ffe2d60ee4c46 /libs | |
| parent | 34fd8b5356f79987473d36084325fba9961dbd2d (diff) | |
Fix initial sync to external time source
TransportMasterStart needs to be set when this cycle's delta
can reach _remaining_latency_preroll.
This allows to directly catch the master-position and start
rolling without initial vari-speed.
Diffstat (limited to 'libs')
| -rw-r--r-- | libs/ardour/session_process.cc | 19 | ||||
| -rw-r--r-- | libs/ardour/transport_master_manager.cc | 3 |
2 files changed, 18 insertions, 4 deletions
diff --git a/libs/ardour/session_process.cc b/libs/ardour/session_process.cc index a157c4a1d5..efc282a52b 100644 --- a/libs/ardour/session_process.cc +++ b/libs/ardour/session_process.cc @@ -1227,6 +1227,16 @@ Session::plan_master_strategy (pframes_t nframes, double master_speed, samplepos return actual_speed (); } + /* When calling TransportMasterStart, sould aim for + * delta >= _remaining_latency_preroll + * This way there can be silent pre-roll of exactly the delta time. + * + * In order to meet this condition, TransportMasterStart needs be set + * if the *end* of the current cycle can reach _remaining_latency_preroll. + * So current_block_size needs to be added here. + */ + const samplecnt_t wlp = worst_latency_preroll_buffer_size_ceil () + current_block_size; + TransportMasterManager& tmm (TransportMasterManager::instance()); const samplecnt_t locate_threshold = 5 * current_block_size; @@ -1279,7 +1289,6 @@ Session::plan_master_strategy (pframes_t nframes, double master_speed, samplepos return 1.0; } - const samplecnt_t wlp = worst_latency_preroll_buffer_size_ceil (); bool should_locate; if (transport_master_strategy.action == TransportMasterNoRoll) { @@ -1366,6 +1375,12 @@ Session::plan_master_strategy (pframes_t nframes, double master_speed, samplepos DEBUG_TRACE (DEBUG::Slave, string_compose ("master @ %1 is WITHIN %2 of our position %3 (delta is %4), so start\n", master_transport_sample, wlp, _transport_sample, delta)); + if (delta > _remaining_latency_preroll) { + /* increase pre-roll to match delta. this allows + * to directly catch the transport w/o vari-speed */ + _remaining_latency_preroll = delta; + } + transport_master_strategy.action = TransportMasterStart; transport_master_strategy.catch_speed = catch_speed; return catch_speed; @@ -1392,7 +1407,7 @@ Session::plan_master_strategy (pframes_t nframes, double master_speed, samplepos samplepos_t locate_target = master_transport_sample; - locate_target += lrintf (ntracks() * sample_rate() * 0.05); + locate_target += wlp + lrintf (ntracks() * sample_rate() * (1.5 * (current_usecs_per_track / 1000000.0))); DEBUG_TRACE (DEBUG::Slave, string_compose ("request locate to master position %1\n", locate_target)); diff --git a/libs/ardour/transport_master_manager.cc b/libs/ardour/transport_master_manager.cc index f3083f7af6..2875021966 100644 --- a/libs/ardour/transport_master_manager.cc +++ b/libs/ardour/transport_master_manager.cc @@ -231,10 +231,9 @@ TransportMasterManager::pre_process_transport_masters (pframes_t nframes, sample if (master_dll_initstate == 0) { init_transport_master_dll (_master_speed, _master_position); - _master_invalid_this_cycle = true; DEBUG_TRACE (DEBUG::Slave, string_compose ("no roll3 - still initializing master DLL, will be %1 next process cycle\n", master_dll_initstate)); - return 1.0; + return _master_speed; } /* compute delta or "error" between the computed master_position for |