Make gain controls step by roughly 1.0/0.1 dB.

Shoot for roughly 30 steps for all controls.

Always keep sensible step information in ParameterDescriptor and just convert
for the UI.

This is a little weird, but it's less weird than it was before, and works.

1 files changed, 5 insertions, 0 deletions

diff --git a/libs/ardour/ardour/dB.h b/libs/ardour/ardour/dB.h
index 4d5f6c9f44..abacdfcd29 100644
--- a/libs/ardour/ardour/dB.h
+++ b/libs/ardour/ardour/dB.h
@@ -34,6 +34,11 @@ static inline float accurate_coefficient_to_dB (float coeff) {
 	return 20.0f * log10f (coeff);
 }
 
+static inline double dB_coeff_step(double max_coeff) {
+	const double max_db = lrint(accurate_coefficient_to_dB(max_coeff));
+	return 0.1 * (max_coeff / max_db);
+}
+
 extern double zero_db_as_fraction;
 
 #endif /* __ardour_dB_h__ */