egui/egui_demo_lib/src/apps/demo/dancing_strings.rs
2021-01-03 18:16:12 +01:00

68 lines
1.9 KiB
Rust

use egui::{containers::*, *};
#[derive(serde::Deserialize, serde::Serialize)]
#[serde(default)]
pub struct DancingStrings {}
impl Default for DancingStrings {
fn default() -> Self {
Self {}
}
}
impl super::Demo for DancingStrings {
fn name(&self) -> &str {
"♫ Dancing Strings"
}
fn show(&mut self, ctx: &CtxRef, open: &mut bool) {
use super::View;
Window::new(self.name())
.open(open)
.default_size(vec2(512.0, 256.0))
.scroll(false)
.show(ctx, |ui| self.ui(ui));
}
}
impl super::View for DancingStrings {
fn ui(&mut self, ui: &mut Ui) {
Frame::dark_canvas(ui.style()).show(ui, |ui| {
ui.ctx().request_repaint();
let time = ui.input().time;
let desired_size = ui.available_width() * vec2(1.0, 0.35);
let (_id, rect) = ui.allocate_space(desired_size);
let mut cmds = vec![];
for &mode in &[2, 3, 5] {
let mode = mode as f32;
let n = 120;
let speed = 1.5;
let points: Vec<Pos2> = (0..=n)
.map(|i| {
let t = i as f32 / (n as f32);
let amp = (time as f32 * speed * mode).sin() / mode;
let y = amp * (t * std::f32::consts::TAU / 2.0 * mode).sin();
pos2(
lerp(rect.x_range(), t),
remap(y, -1.0..=1.0, rect.y_range()),
)
})
.collect();
let thickness = 10.0 / mode;
cmds.push(paint::PaintCmd::line(
points,
Stroke::new(thickness, Color32::from_additive_luminance(196)),
));
}
ui.painter().extend(cmds);
});
ui.add(crate::__egui_github_link_file!());
}
}