use egui::widgets::plot::Values;

let v: Vec<MyType>;
let values = v.iter()
    // do the iterator things
    .map(|my| [my.x(), my.y()])
    .collect::<Values>();

use egui::widgets::plot::{Value, Values};

let v: Vec<MyType>;
let iter = v.iter()
    // do the iterator things
    .map(|my| Value::new(my.x(), my.y()));
let values = Values::from_values_iter(iter);