AudioKit newbie: How to build a VCO with an invertable envelope on its pitch?

[Henri Hagenow]

Hi AudioKids!

I am still trying hard to find out how to modulate the pitch of an oscillator by an envelope, with the option of controlling the amount of modulation (depth).
I posted my question on Stackoverflow: https://stackoverflow.com/questions/49208551/audiokit-how-to-build-a-vco-with-an-invertable-envelope-on-its-pitch

Thanx for any help!

[headkit]

I gave it another try, getting another error, posted a new question here: https://stackoverflow.com/questions/49241328/audiokit-how-to-cast-akoperation-parameter-values-to-double-type