egui/emigui/src/containers/floating.rs

104 lines
2.9 KiB
Rust

//! A Floating is a region that has no parent, it floats on the background.
//! It is potentioally movable.
//! It has no frame or own size.
//! It is the foundation for a window
use std::{fmt::Debug, hash::Hash, sync::Arc};
use crate::*;
#[derive(Clone, Copy, Debug)]
pub struct State {
/// Last known pos
pub pos: Pos2,
/// Last know size. Used for catching clicks.
pub size: Vec2,
}
// TODO: rename Floating to something else.
#[derive(Clone, Copy, Debug)]
pub struct Floating {
id: Id,
movable: bool,
default_pos: Option<Pos2>,
}
impl Floating {
pub fn new(id_source: impl Hash) -> Self {
Self {
id: Id::new(id_source),
movable: true,
default_pos: None,
}
}
pub fn movable(mut self, movable: bool) -> Self {
self.movable = movable;
self
}
pub fn default_pos(mut self, default_pos: Pos2) -> Self {
self.default_pos = Some(default_pos);
self
}
}
impl Floating {
pub fn show(self, ctx: &Arc<Context>, add_contents: impl FnOnce(&mut Region)) {
let default_pos = self.default_pos.unwrap_or_else(|| pos2(100.0, 100.0)); // TODO
let id = ctx.register_unique_id(self.id, "Floating", default_pos);
let layer = Layer::Window(id);
let (mut state, _is_new) = match ctx.memory.lock().get_floating(id) {
Some(state) => (state, false),
None => {
let state = State {
pos: default_pos,
size: Vec2::zero(),
};
(state, true)
}
};
state.pos = state.pos.round();
let mut region = Region::new(
ctx.clone(),
layer,
id,
Rect::from_min_size(state.pos, Vec2::infinity()),
);
add_contents(&mut region);
state.size = region.bounding_size().ceil();
let rect = Rect::from_min_size(state.pos, state.size);
let move_interact = ctx.interact(layer, &rect, Some(id.with("move")));
if move_interact.active {
state.pos += ctx.input().mouse_move;
}
// Constrain to screen:
let margin = 32.0;
state.pos = state.pos.max(pos2(margin - state.size.x, 0.0));
state.pos = state.pos.min(pos2(
ctx.input.screen_size.x - margin,
ctx.input.screen_size.y - margin,
));
state.pos = state.pos.round();
if move_interact.active || mouse_pressed_on_floating(ctx, id) {
ctx.memory.lock().move_floating_to_top(id);
}
ctx.memory.lock().set_floating_state(id, state);
}
}
fn mouse_pressed_on_floating(ctx: &Context, id: Id) -> bool {
if let Some(mouse_pos) = ctx.input.mouse_pos {
ctx.input.mouse_pressed && ctx.memory.lock().layer_at(mouse_pos) == Layer::Window(id)
} else {
false
}
}