unify callbacks with & without graphics & window

src_testbed/harness/mod.rs

@@ -1,4 +1,8 @@
-use crate::physics::{PhysicsEvents, PhysicsState};
+use crate::{
+    physics::{PhysicsEvents, PhysicsState},
+    GraphicsManager,
+};
+use kiss3d::window::Window;
 use plugin::HarnessPlugin;
 use rapier::dynamics::{IntegrationParameters, JointSet, RigidBodySet};
 use rapier::geometry::{BroadPhase, ColliderSet, NarrowPhase};
@@ -48,7 +52,17 @@ pub struct Harness {
     pub state: RunState,
 }
 
-type Callbacks = Vec<Box<dyn FnMut(&mut PhysicsState, &PhysicsEvents, &RunState)>>;
+type Callbacks = Vec<
+    Box<
+        dyn FnMut(
+            Option<&mut Window>,
+            Option<&mut GraphicsManager>,
+            &mut PhysicsState,
+            &PhysicsEvents,
+            &RunState,
+        ),
+    >,
+>;
 
 #[allow(dead_code)]
 impl Harness {
@@ -130,7 +144,15 @@ impl Harness {
         self.plugins.push(Box::new(plugin));
     }
 
-    pub fn add_callback<F: FnMut(&mut PhysicsState, &PhysicsEvents, &RunState) + 'static>(
+    pub fn add_callback<
+        F: FnMut(
+                Option<&mut Window>,
+                Option<&mut GraphicsManager>,
+                &mut PhysicsState,
+                &PhysicsEvents,
+                &RunState,
+            ) + 'static,
+    >(
         &mut self,
         callback: F,
     ) {
@@ -138,6 +160,14 @@ impl Harness {
     }
 
     pub fn step(&mut self) {
+        self.step_with_graphics(None, None);
+    }
+
+    pub fn step_with_graphics(
+        &mut self,
+        window: Option<&mut Window>,
+        graphics: Option<&mut GraphicsManager>,
+    ) {
         #[cfg(feature = "parallel")]
         {
             let physics = &mut self.physics;
@@ -180,8 +210,26 @@ impl Harness {
             plugin.step(&mut self.physics, &self.state)
         }
 
-        for f in &mut self.callbacks {
-            f(&mut self.physics, &self.events, &self.state)
+        // FIXME: This assumes either window & graphics are Some, or they are all None
+        // this is required as we cannot pass Option<&mut Window> & Option<&mut GraphicsManager directly in a loop
+        // there must be a better way of doing this?
+        match (window, graphics) {
+            (Some(window), Some(graphics)) => {
+                for f in &mut self.callbacks {
+                    f(
+                        Some(window),
+                        Some(graphics),
+                        &mut self.physics,
+                        &self.events,
+                        &self.state,
+                    );
+                }
+            }
+            _ => {
+                for f in &mut self.callbacks {
+                    f(None, None, &mut self.physics, &self.events, &self.state);
+                }
+            }
         }
 
         for plugin in &mut self.plugins {

src_testbed/testbed.rs

@@ -3,10 +3,10 @@ use std::mem;
 use std::path::Path;
 use std::rc::Rc;
 
-use crate::engine::GraphicsManager;
-use crate::physics::{PhysicsSnapshot, PhysicsState};
+use crate::physics::{PhysicsEvents, PhysicsSnapshot, PhysicsState};
 use crate::plugin::TestbedPlugin;
 use crate::ui::TestbedUi;
+use crate::{engine::GraphicsManager, harness::RunState};
 
 use kiss3d::camera::Camera;
 use kiss3d::event::Event;
@@ -392,6 +392,21 @@ impl Testbed {
         self.plugins.clear();
     }
 
+    pub fn add_callback<
+        F: FnMut(
+                Option<&mut Window>,
+                Option<&mut GraphicsManager>,
+                &mut PhysicsState,
+                &PhysicsEvents,
+                &RunState,
+            ) + 'static,
+    >(
+        &mut self,
+        callback: F,
+    ) {
+        self.harness.add_callback(callback);
+    }
+
     pub fn add_plugin(&mut self, plugin: impl TestbedPlugin + 'static) {
         self.plugins.push(Box::new(plugin));
     }
@@ -1221,7 +1236,9 @@ impl State for Testbed {
         if self.state.running != RunMode::Stop {
             for _ in 0..self.nsteps {
                 if self.state.selected_backend == RAPIER_BACKEND {
-                    self.harness.step();
+                    let graphics = &mut self.graphics;
+                    self.harness
+                        .step_with_graphics(Some(window), Some(graphics));
 
                     for plugin in &mut self.plugins {
                         plugin.step(&mut self.harness.physics)