add example for bevy-egui #67

Cargo.toml

@@ -3,3 +3,4 @@ members = [
     "egui_node_graph",
     "egui_node_graph_example",
 ]
+resolver = "2"

egui_node_graph/Cargo.toml

@@ -20,3 +20,9 @@ slotmap = { version = "1.0" }
 smallvec = { version = "1.7.0" }
 serde = { version = "1.0", optional = true, features = ["derive"] }
 thiserror = "1.0"
+
+[dev-dependencies]
+anyhow = "1.0.68"
+bevy = "0.9.1"
+bevy_egui = "0.17"
+eframe = "0.19.0"

egui_node_graph/examples/bevy.rs

@@ -0,0 +1,67 @@
+mod node_graph;
+
+use std::collections::HashMap;
+
+use bevy::prelude::*;
+use bevy_egui::{EguiContext, EguiPlugin};
+use egui::TextStyle;
+use egui_node_graph::*;
+use node_graph::*;
+
+impl NodeGraphExample {
+    fn draw(&mut self, ctx: &egui::Context) {
+        egui::TopBottomPanel::top("top").show(ctx, |ui| {
+            egui::menu::bar(ui, |ui| {
+                egui::widgets::global_dark_light_mode_switch(ui);
+            });
+        });
+        let graph_response = egui::CentralPanel::default()
+            .show(ctx, |ui| {
+                self.state
+                    .draw_graph_editor(ui, AllMyNodeTemplates, &mut self.user_state)
+            })
+            .inner;
+        for node_response in graph_response.node_responses {
+            // Here, we ignore all other graph events. But you may find
+            // some use for them. For example, by playing a sound when a new
+            // connection is created
+            if let NodeResponse::User(user_event) = node_response {
+                match user_event {
+                    MyResponse::SetActiveNode(node) => self.user_state.active_node = Some(node),
+                    MyResponse::ClearActiveNode => self.user_state.active_node = None,
+                }
+            }
+        }
+
+        if let Some(node) = self.user_state.active_node {
+            if self.state.graph.nodes.contains_key(node) {
+                let text = match evaluate_node(&self.state.graph, node, &mut HashMap::new()) {
+                    Ok(value) => format!("The result is: {:?}", value),
+                    Err(err) => format!("Execution error: {}", err),
+                };
+                ctx.debug_painter().text(
+                    egui::pos2(10.0, 35.0),
+                    egui::Align2::LEFT_TOP,
+                    text,
+                    TextStyle::Button.resolve(&ctx.style()),
+                    egui::Color32::WHITE,
+                );
+            } else {
+                self.user_state.active_node = None;
+            }
+        }
+    }
+}
+
+fn draw_graph(mut context: ResMut<EguiContext>, mut graph: ResMut<NodeGraphExample>) {
+    graph.draw(context.ctx_mut());
+}
+
+fn main() {
+    App::new()
+        .add_plugins(DefaultPlugins)
+        .add_plugin(EguiPlugin)
+        .init_resource::<NodeGraphExample>()
+        .add_system(draw_graph)
+        .run();
+}

egui_node_graph/examples/eframe.rs

@@ -0,0 +1,96 @@
+mod node_graph;
+
+use std::collections::HashMap;
+
+use egui::TextStyle;
+use egui_node_graph::NodeResponse;
+use node_graph::*;
+
+#[cfg(feature = "persistence")]
+const PERSISTENCE_KEY: &str = "egui_node_graph";
+
+#[cfg(feature = "persistence")]
+impl NodeGraphExample {
+    pub fn new(cc: &eframe::CreationContext<'_>) -> Self {
+        let state = cc
+            .storage
+            .and_then(|storage| eframe::get_value(storage, PERSISTENCE_KEY))
+            .unwrap_or_default();
+
+        Self {
+            state,
+            user_state: MyGraphState::default(),
+        }
+    }
+}
+
+impl eframe::App for NodeGraphExample {
+    #[cfg(feature = "persistence")]
+    /// If the persistence function is enabled,
+    /// Called by the frame work to save state before shutdown.
+    fn save(&mut self, storage: &mut dyn eframe::Storage) {
+        eframe::set_value(storage, PERSISTENCE_KEY, &self.state);
+    }
+    /// Called each time the UI needs repainting, which may be many times per second.
+    /// Put your widgets into a `SidePanel`, `TopPanel`, `CentralPanel`, `Window` or `Area`.
+    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
+        egui::TopBottomPanel::top("top").show(ctx, |ui| {
+            egui::menu::bar(ui, |ui| {
+                egui::widgets::global_dark_light_mode_switch(ui);
+            });
+        });
+        let graph_response = egui::CentralPanel::default()
+            .show(ctx, |ui| {
+                self.state
+                    .draw_graph_editor(ui, AllMyNodeTemplates, &mut self.user_state)
+            })
+            .inner;
+        for node_response in graph_response.node_responses {
+            // Here, we ignore all other graph events. But you may find
+            // some use for them. For example, by playing a sound when a new
+            // connection is created
+            if let NodeResponse::User(user_event) = node_response {
+                match user_event {
+                    MyResponse::SetActiveNode(node) => self.user_state.active_node = Some(node),
+                    MyResponse::ClearActiveNode => self.user_state.active_node = None,
+                }
+            }
+        }
+
+        if let Some(node) = self.user_state.active_node {
+            if self.state.graph.nodes.contains_key(node) {
+                let text = match evaluate_node(&self.state.graph, node, &mut HashMap::new()) {
+                    Ok(value) => format!("The result is: {:?}", value),
+                    Err(err) => format!("Execution error: {}", err),
+                };
+                ctx.debug_painter().text(
+                    egui::pos2(10.0, 35.0),
+                    egui::Align2::LEFT_TOP,
+                    text,
+                    TextStyle::Button.resolve(&ctx.style()),
+                    egui::Color32::WHITE,
+                );
+            } else {
+                self.user_state.active_node = None;
+            }
+        }
+    }
+}
+
+fn main() {
+    use eframe::egui::Visuals;
+
+    eframe::run_native(
+        "Egui node graph example",
+        eframe::NativeOptions::default(),
+        Box::new(|cc| {
+            cc.egui_ctx.set_visuals(Visuals::dark());
+            #[cfg(feature = "persistence")]
+            {
+                Box::new(NodeGraphExample::new(cc))
+            }
+            #[cfg(not(feature = "persistence"))]
+            Box::new(NodeGraphExample::default())
+        }),
+    );
+}