Function sapling_note_encryption 

pub fn sapling_note_encryption<R: RngCore>(
    ovk: Option<OutgoingViewingKey>,
    note: Note,
    memo: [u8; 512],
    rng: &mut R,
) -> NoteEncryption<SaplingDomain>

Creates a new encryption context for the given note.

Setting ovk to None represents the ovk = ⊥ case, where the note cannot be recovered by the sender.

NB: the example code here only covers the post-Canopy case.

Examples

use ff::Field;
use rand_core::OsRng;
use sapling_crypto::{
    keys::OutgoingViewingKey,
    note_encryption::{sapling_note_encryption, Zip212Enforcement},
    util::generate_random_rseed,
    value::{NoteValue, ValueCommitTrapdoor, ValueCommitment},
    Diversifier, PaymentAddress, Rseed, SaplingIvk,
};

let mut rng = OsRng;

let ivk = SaplingIvk(jubjub::Scalar::random(&mut rng));
let diversifier = Diversifier([0; 11]);
let to = ivk.to_payment_address(diversifier).unwrap();
let ovk = Some(OutgoingViewingKey([0; 32]));

let value = NoteValue::from_raw(1000);
let rcv = ValueCommitTrapdoor::random(&mut rng);
let cv = ValueCommitment::derive(value, rcv);
let rseed = generate_random_rseed(
    Zip212Enforcement::GracePeriod,
    &mut rng,
);
let note = to.create_note(value, rseed);
let cmu = note.cmu();

let mut enc = sapling_note_encryption(ovk, note, [0x37; 512], &mut rng);
let encCiphertext = enc.encrypt_note_plaintext();
let outCiphertext = enc.encrypt_outgoing_plaintext(&cv, &cmu, &mut rng);