Add time as input to emigui to enable animations

emigui/src/style.rs

@@ -26,6 +26,10 @@ pub struct Style {
     /// For stuff like check marks in check boxes.
     pub line_width: f32,
 
+    // TODO: add ability to disable animations!
+    /// How many seconds a typical animation should last
+    pub animation_time: f32,
+
     pub window: Window,
 }
 
@@ -44,6 +48,7 @@ impl Default for Style {
             clickable_diameter: 34.0,
             start_icon_width: 20.0,
             line_width: 1.0,
+            animation_time: 1.0 / 20.0,
             window: Window::default(),
         }
     }