Unable to play note in synth using c api

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1

i've been losing my mind over the last couple hours trying to get the synth to play a note using the c api. current code i have can be summarised as follows:

SoundChannel* sound_effects = NULL;
PDSynth* projectile_sound = NULL;
// ....
snd = pd->sound;
// ...
sound_effects = snd->channel->newChannel();
projectile_sound = snd->synth->newSynth();
snd->channel->addSource(sound_effects, (SoundSource*)projectile_sound);
snd->channel->setVolume(sound_effects, 1.f);

snd->synth->setWaveform(projectile_sound, kWaveformSquare);
snd->synth->setAttackTime(projectile_sound, 0.f);
snd->synth->setDecayTime(projectile_sound, 0.f);
snd->synth->setSustainLevel(projectile_sound, 1.f);
snd->synth->setReleaseTime(projectile_sound, 0.1f);
xsnd->synth->setVolume(projectile_sound, 1.f, 1.f);
// ...
snd->synth->playNote(projectile_sound, 700.f, 1.f, 0.1f, 0);

happy to provide more if helpful, but i think this gives a good idea of where im at right now. given this code, i'm unable to make sounds either in the simulator or the actual hardware.

2

It's an easy fix, but not at all obvious: just need to add snd->addChannel(sound_effects);

We do that automatically on the Lua side, so we should in C as well. I'll get that change in as soon as I can!

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3

i thought it was going to be something like that, must have missed it in the documentation. thank you heaps!

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4

I'm new here so forgive me if I missed this in the change logs of previous versions but did this get added to the C API?

If so, am I correct in assuming this happens in playdate->sound->channel->newChannel();?

Thanks! I'm just learning the C API now and writing personal notes as I go.

5

According to the issue tracker, as of 1.12.0 snd->channel->newChannel() adds the channel to the audio engine after creating it. There should no longer be any need for an additional addChannel() call.

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