Is there documentation on clap_event_transport

[sagantech]

Specifically there is this in events.h:

clap_beattime song_pos_beats; // position in beats

clap_beattime is defined as int64_t. So song_pos_beats is a 64 bit integer. What are the units of measurement? With VST2 it was a double and at least documented as "Musical Position, in Quarter Note (1.0 equals 1 Quarter Note)"

Can anyone help me here?

[robbert-vdh]

There's a comment on how to use these fixed point numbers just above that definition for clap_beattime:

clap/include/clap/fixedpoint.h

Lines 6 to 16 in af1e05c

	/// We use fixed point representation of beat time and seconds time
	/// Usage:
	/// double x = ...; // in beats
	/// clap_beattime y = round(CLAP_BEATTIME_FACTOR * x);
	// This will never change
	static const CLAP_CONSTEXPR int64_t CLAP_BEATTIME_FACTOR = 1LL << 31;
	static const CLAP_CONSTEXPR int64_t CLAP_SECTIME_FACTOR = 1LL << 31;
	typedef int64_t clap_beattime;
	typedef int64_t clap_sectime;

And the length of a beat is determined by the tempo. So at a tempo of 174 beats per minute, a beat takes 60 / 174 ≈ 0.345 seconds. VST2 and VST3 use the term quarter note here, but I'm fairly sure they all refer to the same thing.

[sagantech]

Thanks I think I understand now. I didn't realize that this was a fixed point integer.

[baconpaul]

If it helps, https://github.com/free-audio/clap-juce-extensions/blob/698e0d05f5a2ac798c8bb30cfceeba5c4cdf45bf/src/wrapper/clap-juce-wrapper.cpp#L454 shows how we bridge the clap data structure to the juce TransportInfo object.

[sagantech]

Yes that is helpful. Thanks.