Move Memory and Region to own files

emigui/src/memory.rs

@@ -0,0 +1,50 @@
+use std::collections::{HashMap, HashSet};
+
+use crate::{window::WindowState, *};
+
+#[derive(Clone, Debug, Default)]
+pub struct Memory {
+    /// The widget being interacted with (e.g. dragged, in case of a slider).
+    pub(crate) active_id: Option<Id>,
+
+    /// Which foldable regions are open.
+    pub(crate) open_foldables: HashSet<Id>,
+
+    windows: HashMap<Id, WindowState>,
+
+    /// Top is last
+    window_order: Vec<Id>,
+}
+
+impl Memory {
+    /// default_rect: where to put it if it does NOT exist
+    pub fn get_or_create_window(&mut self, id: Id, default_rect: Rect) -> WindowState {
+        if let Some(state) = self.windows.get(&id) {
+            *state
+        } else {
+            let state = WindowState { rect: default_rect };
+            self.windows.insert(id, state);
+            self.window_order.push(id);
+            state
+        }
+    }
+
+    pub fn set_window_state(&mut self, id: Id, state: WindowState) {
+        self.windows.insert(id, state);
+    }
+
+    pub fn layer_at(&self, pos: Vec2) -> Layer {
+        for window_id in self.window_order.iter().rev() {
+            if let Some(state) = self.windows.get(window_id) {
+                if state.rect.contains(pos) {
+                    return Layer::Window(*window_id);
+                }
+            }
+        }
+        Layer::Background
+    }
+
+    pub fn move_window_to_top(&mut self, _id: Id) {
+        // TODO
+    }
+}