fyrox_impl/scene/graph/
event.rs

1// Copyright (c) 2019-present Dmitry Stepanov and Fyrox Engine contributors.
2//
3// Permission is hereby granted, free of charge, to any person obtaining a copy
4// of this software and associated documentation files (the "Software"), to deal
5// in the Software without restriction, including without limitation the rights
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7// copies of the Software, and to permit persons to whom the Software is
8// furnished to do so, subject to the following conditions:
9//
10// The above copyright notice and this permission notice shall be included in all
11// copies or substantial portions of the Software.
12//
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14// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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19// SOFTWARE.
20
21//! Graph event broadcaster allows you to receive graph events such as node deletion or addition.
22//! Check [GraphEventBroadcaster::subscribe] for examples.
23
24use crate::{core::pool::Handle, scene::node::Node};
25use std::{
26    fmt::{Debug, Formatter},
27    sync::mpsc::Sender,
28};
29
30/// An event that happened in a graph.
31#[derive(Clone, PartialEq, Debug, Eq)]
32pub enum GraphEvent {
33    /// A node was added.
34    Added(Handle<Node>),
35    /// A node was removed.
36    Removed(Handle<Node>),
37}
38
39/// Graph event broadcaster allows you to receive graph events such as node deletion or addition.
40/// Check [GraphEventBroadcaster::subscribe] for examples.
41#[derive(Default)]
42pub struct GraphEventBroadcaster {
43    senders: Vec<Sender<GraphEvent>>,
44}
45
46impl Debug for GraphEventBroadcaster {
47    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
48        write!(
49            f,
50            "GraphEventBroadcaster has {} senders.",
51            self.senders.len()
52        )
53    }
54}
55
56impl GraphEventBroadcaster {
57    /// Adds new subscriber, an instance of [Sender].
58    ///
59    /// # Examples
60    ///
61    /// ```rust
62    /// # use std::sync::mpsc::channel;
63    /// # use fyrox_impl::scene::base::BaseBuilder;
64    /// # use fyrox_impl::scene::graph::event::GraphEvent;
65    /// # use fyrox_impl::scene::graph::Graph;
66    /// # use fyrox_impl::scene::pivot::PivotBuilder;
67    /// # use fyrox_impl::graph::BaseSceneGraph;
68    ///
69    /// let mut graph = Graph::new();
70    ///
71    /// let (tx, rx) = channel();
72    /// graph.event_broadcaster.subscribe(tx);
73    ///
74    /// // Add a node
75    /// let handle = PivotBuilder::new(BaseBuilder::new()).build(&mut graph);
76    ///
77    /// assert_eq!(rx.recv(), Ok(GraphEvent::Added(handle)));
78    ///
79    /// graph.remove_node(handle);
80    ///
81    /// assert_eq!(rx.recv(), Ok(GraphEvent::Removed(handle)));
82    ///
83    /// ```
84    pub fn subscribe(&mut self, sender: Sender<GraphEvent>) {
85        self.senders.push(sender);
86    }
87
88    pub(crate) fn broadcast(&mut self, event: GraphEvent) {
89        self.senders
90            .retain_mut(|sender| sender.send(event.clone()).is_ok());
91    }
92}
fyrox_impl/scene/graph/event.rs

fyrox_impl/scene/graph/
event.rs
