Applying envelope to RP2040 PWM output

[Mickeyluv]

I want to apply a simple AR envelope to the PWM output of the Hagiwo chord VCO V2. My thought is to use a variable 'envelope_level' which is an integer value (say, 0-511) that follows the attack and decay cycles.

Presumably the output levels are set by, for example;
pwm_set_chan_level(slice_num, PWM_CHAN_A, wavetable[(int)osc_progress[0]]/4+wavetable[(int)osc_progress[1]]/4+wavetable[(int)osc_progress[3]]/4+511);

How should the envelope be applied so that the output ranges from silent through to the original level?

I'm thinking that envelope_level could be normalised in the range 0 to 1 and used to multiply
wavetable[(int)osc_progress[0]]/4+wavetable[(int)osc_progress[1]]/4+wavetable[(int)osc_progress[3]]/4 before adding the 511 offset. Is this correct?

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RP2040 Chord VCO V2.ino.txt
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[Mickeyluv]

Just done some experimenting and found that multiplying by envelope_level then dividing by 511 before adding 511 works fine.