Questions about the new clip launcher

ToxVox · March 6, 2024, 11:10am

I’m trying to figure out the new feature clip launcher feature at the develop-branch. Maybe I’m too early with my questions…

I checked classes like ClipSlotList, ClipSlot, SceneList, Scene, LaunchHandle
and came up with this structure:

Here is my interpretation of it:
Scene is managed by SceneList. Scene creates ClipSlots to all available AudioTracks. A Clip lives in a ClipSlot and is managed by the ClipSlotList. An AudioTrack owns the ClipSlotList. If I want to launch a clip, I should use the LaunchHandle thats belongs to the Clip.

For a simple test I wrote this code:

edit->getSceneList().insertScene(0);
audioTrack1->getClipSlotList().getClipSlots()[0]->setClip(audioClip1);
audioTrack1->getClipSlotList().getClipSlots()[0]->getClip()->getLaunchHandle()->play( tracktion::MonotonicBeat(  { 0_bp } ) );

Is this the right direction? Did I miss something?

dave96 · March 6, 2024, 11:45am

No, that’s correct.
The MonotonicBeat is the point in the future that you want to launch it though. If you want to launch it immediately, just pass an empty optional i.e. play ({}).
Although a MonotonicBeat (0_bp) will probably do the same thing as 0_bp is likely to be in the past and hence launched immediately.

It is a bit early to rely on the exact APIs and behaviour though. It won’t be fixed until we release v3.0 of the Engine.

Also note that the feature/launcher branch is a technical preview so can’t be commercially licensed yet.

ToxVox · March 7, 2024, 7:35pm

Thanks for the hint @dave96!
In my code example the ->getClip() doesn’t work correct. I’m getting an error
JUCE Message Thread (1): EXC_BAD_ACCESS (code=1, address=0x0)
Should I call something between ->setClip() and ->getClip ?

Do you have a rough roadmap or schedule for v3.0?

For my project, I will publish it open source.

dave96 · March 8, 2024, 1:26pm

Can you step through the SceneList::insertScene and see if it’s actually adding the slots to the ClipSlotLists?

Can you call auto clipSlots = audioTrack1->getClipSlotList().getClipSlots() and see what it’s contents is?

ToxVox · March 13, 2024, 1:36pm

@dave96 Yes, I think this part is ok…

Here is the result:

Below is the complete code:

github.com

toxvox/BentoClipLauncher/blob/master/BentoClipLauncher/Source/BentoClipLauncher.h

/*
 ==============================================================================
 
 BentoClipLauncher.h
 Created: 03 March 2024 10:58:42am
 Author:  Halil Kleinmann
 
 ==============================================================================
 */

#pragma once

#include <JuceHeader.h>

#include "common/Utilities.h"
//#include "common/BinaryData.h"

using namespace std::literals;
using namespace tracktion::literals;

This file has been truncated. show original

dave96 · March 14, 2024, 10:17am

Can you step in to the setClip call and see if it’s adding the clip state?

ToxVox · March 14, 2024, 10:50am

Do you mean this spot here?

ToxVox · March 18, 2024, 10:16am

@dave96 I checked the setClip-section again. Seems like dynamic_cast<ClipTrack*> (&newParent) fails in my case…

bool Clip::moveTo (ClipOwner& newParent)
{
    if (auto to = dynamic_cast<ClipTrack*> (&newParent))
    {
        if (canBeAddedTo (*to))
        {
            if (parent != to)
            {
                if (! to->isFrozen (Track::anyFreeze))
                {
                    Clip::Ptr refHolder (this);
                    to->addClip (this);
                }
            }
            return true;
        }
    }
    return false;
}

I’m getting true if I check it with tracktion::Clip::isClipState(stepClip1->state);

dave96 · March 20, 2024, 3:59pm

Does this work for you:

ToxVox · March 20, 2024, 10:41pm

Yes, it works better. But I have another issue here:

void ClipSlot::setClip (Clip* c)
{
    if (c == nullptr)
        return;

    if (auto existingClip = getClip())
        existingClip->removeFromParent();

    jassert (findClipForID (c->itemID) == nullptr);  <== No matching function for call to 'findClipForID'

    auto um = c->getUndoManager();
    c->state.getParent().removeChild (c->state, um);
    state.addChild (c->state, -1, um);
}

It works when I comment this out: jassert (findClipForID (c->itemID) == nullptr);

Now I’m playing around with the LaunchHandle. If I start a clip (while the transport is playing) I hear a very short part (like a short click sound) of it. My approach is to launch and stop a clip with a quantisation of 1 bar. The clip should loop until I stop it. This is my code:

switch(launchHandle->getPlayingStatus())
{
    case tracktion::LaunchHandle::PlayState::playing:
    {
        launchHandle->stop( tracktion::MonotonicBeat( {} ) );
        break;
    }
    case tracktion::LaunchHandle::PlayState::stopped:
    {
        launchHandle->play( tracktion::MonotonicBeat( {} ) );
        break;
    }
}

Should I use other function like the FollowActions?

dave96 · March 25, 2024, 1:56pm

jassert (findClipForID (c->itemID) == nullptr); <== No matching function for call to 'findClipForID
I thought this was fixed? Can you grab the latest and try again please?

tracktion::MonotonicBeat( {} ) means, “as soon as possible”, i.e. not in the future so it sounds like you’re starting and stopping it straight away.

You probably want to look at Edit::getLaunchQuantisation()

ToxVox · April 2, 2024, 10:02pm

@dave96 Congratulation to the Tracktion 13 launch! The new clip launcher works well!

I got the latest version but didn’t help:

As I mentioned, it works for me if I comment the line out.

I think I figure it out how the new tracktion::MonotonicBeat works. It’s like a parallel beat based timeline - right? And the clip launcher syncs the clip start and stop to it.

With this code I can synced launch / stop the clip with 1 bar quantisation (4_bd) :

auto& ts = edit->tempoSequence;
auto& tc = edit->getTransport();            
tracktion::MonotonicBeat startSyncBeat;
tracktion::MonotonicBeat endSyncBeat;

const auto currentBarsBeats = ts.toBarsAndBeats (tc.getPosition());
const auto barStartBeat = ts.toBeats (tracktion::tempo::BarsAndBeats { .bars = currentBarsBeats.bars });
startSyncBeat = tracktion::MonotonicBeat { barStartBeat + 4_bd };
endSyncBeat = tracktion::MonotonicBeat { barStartBeat + 4_bd }; 
.
.
.
switch(launchHandle->getPlayingStatus())
{
    case tracktion::LaunchHandle::PlayState::playing:
    {
        DBG("barStartBeat - Stop:" + juce::String( endSyncBeat.v.inBeats() ) );
        launchHandle->stop( endSyncBeat );
        break;
    }
    case tracktion::LaunchHandle::PlayState::stopped:
    {
        DBG("barStartBeat - Start:" + juce::String( startSyncBeat.v.inBeats() ) );
        launchHandle->play( startSyncBeat );
        break;
    }
}

Currently the clips are played as one shots. How can I loop it? This function didn’t help:
stepClip->setLoopRangeBeats( {0_bp, 4_bp} );

ToxVox · April 9, 2024, 11:41am

I’m exploring the Waveform 13. I can’t find the right place to set clips in a loop mode.

@dave96 Can you give me a hint where the “Loop” checkbox activate the loop, please?

Thanks!

dave96 · April 9, 2024, 3:52pm

“Loop” is just if the loop length is non-zero.
If you set the loop length in beats, you also need to enable “auto-tempo”.

Sorry I’m being slow to respond but the clip launcher branch isn’t really ready for public consumption yet so I can’t really prioritise it this soon after a major app launch I’m afraid.

ToxVox · April 9, 2024, 9:09pm

If I understand you correctly, does ‘non-zero’ mean a value greater than zero?.
My code ( stepClip->setLoopRangeBeats( {0_bp, 4_bp} ); ) should work - right?
I can’t set up “auto-tempo” for StepClip. I only found it for AudioClipBase.

No worries about the delayed response, I’m grateful for your insight and guidance.

dave96 · April 11, 2024, 3:41pm

I think that should work… Maybe debug in LoopingMidiNode to see if it’s not getting the correct loop region?

ToxVox · April 11, 2024, 10:22pm

Finally it works!

This is my quick’n’dirty solution for a clip launch button:

clipLaunchButton2.onClick = [this]
{
    auto& ts = edit->tempoSequence;
    auto& tc = edit->getTransport();
    
    tracktion::MonotonicBeat startSyncBeat;
    tracktion::MonotonicBeat endSyncBeat;
    const auto currentBarsBeats = ts.toBarsAndBeats (tc.getPosition());
    const auto barStartBeat = ts.toBeats (tracktion::tempo::BarsAndBeats { .bars = currentBarsBeats.bars });
    startSyncBeat = tracktion::MonotonicBeat { barStartBeat + 4_bd };
    endSyncBeat = tracktion::MonotonicBeat { barStartBeat + 4_bd };

    stopAllClips(endSyncBeat);
    audioTrack1->getClipSlotList().getClipSlots()[1]->getClip()->setLoopRangeBeats( { 0_bp, 4_bp } );
    audioTrack1->getClipSlotList().getClipSlots()[1]->getClip()->getLaunchHandle()->play( startSyncBeat );
};

I schedule a stop clip for every clip in the ClipSlotList before launching another clip in the slot list. Or is there a build in function for this clip launch behaviour?

void stopAllClips(std::optional<tracktion::MonotonicBeat> endSyncBeat)
{
    for( auto clipSlot : audioTrack1->getClipSlotList().getClipSlots() )
    {
        if(clipSlot)
        {
            if(auto clip = clipSlot->getClip())
            {
                if(auto launchHandle = clip->getLaunchHandle())
                {
                    launchHandle->stop( endSyncBeat) ;
                }
            }
        }
    }
}

dave96 · April 15, 2024, 10:41am

That’s pretty good, just a few quick comments.

Rather than doing your manual toBarsAndBeats calculation, you can use the LaunchQuantisation class which effectively does this for you.
This is just the same calculation so no point in doing it twice.

    startSyncBeat = tracktion::MonotonicBeat { barStartBeat + 4_bd };
    endSyncBeat = tracktion::MonotonicBeat { barStartBeat + 4_bd };

No that’s what we do currently. You could optimise by keeping track of all the playing or queued clips but it wouldn’t be much more efficient.

Or is there a build in function for this clip launch behaviour?

What you’ve got will probably only work once when play starts from the beginning. The MonotonicBeat continues during playback so you need to find the “current” MonotonicBeat and use that as a reference. In Waveform what we do is get the current sync point from the current sync point from the EditPlaybackContext::getSyncPoint(), find the next BeatPosition to launch at using LaunchQuantisation and SyncPoint::beat. Find the duration number of beats between the current beat position and the launch position, then add that on to the SyncPoint::MonotonicBeat to find out where to launch/stop the clips.

ToxVox · April 23, 2024, 10:40am

It seams there was little bit refactoring in case of targeting a track to send midi data.

In my scenario we have two audio tracks and I want to switch between this tracks and send send midi notes via GUI to the selected one. But I can reach audioTrackB with midi data only. Did I miss something @dave96 ?

This are my steps:

Create a virtual midi device
- tracktion::VirtualMidiInputDevice* virtualMidiInputDevice;
- engine.getDeviceManager().createVirtualMidiDevice ("myVirtualMidiDevice");
- Enable midi in with VirtualMidiInputDevice::setEnabled ()
Prepare a button to send midi notes

sendMidiNoteButton.onClick = [this]
{
        auto midiNote = juce::MidiMessage::noteOff(1, 36, 100);
        virtualMidiInputDevice->handleIncomingMidiMessage(nullptr, midiNote);  
};
  
sendMidiNoteButton.onStateChange = [this]
{
    if(sendMidiNoteButton.isDown())
    {
        auto midiNote = juce::MidiMessage::noteOn(1, 36, 100);
        virtualMidiInputDevice->handleIncomingMidiMessage(nullptr, midiNote); 
    }
};

Switch between audioTrackA and audioTrackB

selectButtonTrackA.onClick = [this]
{
    for (auto instance : edit->getAllInputDevices())
    {
        if("myVirtualMidiDevice" == instance->getInputDevice().getName())
        {
            auto result = instance->setTarget(audioTrackA->itemID, true, nullptr, 0);
            auto removeTargetResult = instance->removeTarget(audioTrackB->itemID, nullptr);          
        }
    }
};

selectButtonTrackB.onClick = [this]
{
    for (auto instance : edit->getAllInputDevices())
    {
        if("myVirtualMidiDevice" == instance->getInputDevice().getName())
        {
            auto result = instance->setTarget(audioTrackB->itemID, true, nullptr, 0);
            auto removeTargetResult = instance->removeTarget(audioTrackA->itemID, nullptr);          
        }
    }
};

RolandMR · April 23, 2024, 12:17pm

Is your input armed? We added a new input monitoring mode “auto”, where midi only processed when input armed. Either arm your input or set monitor mode to “on”.

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