feat: add runtime play tick and play-mode scene editing semantics

editor/src/Core/PlaySessionController.cpp

@@ -0,0 +1,122 @@
+#include "Core/PlaySessionController.h"
+
+#include "Core/EditorEvents.h"
+#include "Core/EventBus.h"
+#include "Core/IEditorContext.h"
+#include "Core/ISceneManager.h"
+#include "Core/IUndoManager.h"
+
+namespace XCEngine {
+namespace Editor {
+
+void PlaySessionController::Attach(IEditorContext& context) {
+    if (m_playStartRequestedHandlerId == 0) {
+        m_playStartRequestedHandlerId = context.GetEventBus().Subscribe<PlayModeStartRequestedEvent>(
+            [this, &context](const PlayModeStartRequestedEvent&) {
+                StartPlay(context);
+            });
+    }
+
+    if (m_playStopRequestedHandlerId == 0) {
+        m_playStopRequestedHandlerId = context.GetEventBus().Subscribe<PlayModeStopRequestedEvent>(
+            [this, &context](const PlayModeStopRequestedEvent&) {
+                StopPlay(context);
+            });
+    }
+
+    if (m_playPauseRequestedHandlerId == 0) {
+        m_playPauseRequestedHandlerId = context.GetEventBus().Subscribe<PlayModePauseRequestedEvent>(
+            [this, &context](const PlayModePauseRequestedEvent&) {
+                PausePlay(context);
+            });
+    }
+}
+
+void PlaySessionController::Detach(IEditorContext& context) {
+    StopPlay(context);
+
+    if (m_playStartRequestedHandlerId != 0) {
+        context.GetEventBus().Unsubscribe<PlayModeStartRequestedEvent>(m_playStartRequestedHandlerId);
+        m_playStartRequestedHandlerId = 0;
+    }
+
+    if (m_playStopRequestedHandlerId != 0) {
+        context.GetEventBus().Unsubscribe<PlayModeStopRequestedEvent>(m_playStopRequestedHandlerId);
+        m_playStopRequestedHandlerId = 0;
+    }
+
+    if (m_playPauseRequestedHandlerId != 0) {
+        context.GetEventBus().Unsubscribe<PlayModePauseRequestedEvent>(m_playPauseRequestedHandlerId);
+        m_playPauseRequestedHandlerId = 0;
+    }
+}
+
+void PlaySessionController::Update(IEditorContext& context, float deltaTime) {
+    (void)context;
+    if (!m_runtimeLoop.IsRunning()) {
+        return;
+    }
+
+    m_runtimeLoop.Tick(deltaTime);
+}
+
+bool PlaySessionController::StartPlay(IEditorContext& context) {
+    if (context.GetRuntimeMode() != EditorRuntimeMode::Edit) {
+        return false;
+    }
+
+    auto& sceneManager = context.GetSceneManager();
+    if (!sceneManager.HasActiveScene()) {
+        return false;
+    }
+
+    m_editorSnapshot = sceneManager.CaptureSceneSnapshot();
+    if (!m_editorSnapshot.hasScene) {
+        return false;
+    }
+
+    if (!sceneManager.RestoreSceneSnapshot(m_editorSnapshot)) {
+        return false;
+    }
+
+    sceneManager.SetSceneDocumentDirtyTrackingEnabled(false);
+    m_runtimeLoop.Start(sceneManager.GetScene());
+    context.GetUndoManager().ClearHistory();
+    context.SetRuntimeMode(EditorRuntimeMode::Play);
+    context.GetEventBus().Publish(PlayModeStartedEvent{});
+    return true;
+}
+
+bool PlaySessionController::StopPlay(IEditorContext& context) {
+    if (!IsEditorRuntimeActive(context.GetRuntimeMode())) {
+        return false;
+    }
+
+    auto& sceneManager = context.GetSceneManager();
+    m_runtimeLoop.Stop();
+    sceneManager.SetSceneDocumentDirtyTrackingEnabled(true);
+
+    if (!sceneManager.RestoreSceneSnapshot(m_editorSnapshot)) {
+        return false;
+    }
+
+    context.GetUndoManager().ClearHistory();
+    context.SetRuntimeMode(EditorRuntimeMode::Edit);
+    context.GetEventBus().Publish(PlayModeStoppedEvent{});
+    m_editorSnapshot = {};
+    return true;
+}
+
+bool PlaySessionController::PausePlay(IEditorContext& context) {
+    if (context.GetRuntimeMode() != EditorRuntimeMode::Play || !m_runtimeLoop.IsRunning()) {
+        return false;
+    }
+
+    m_runtimeLoop.Pause();
+    context.SetRuntimeMode(EditorRuntimeMode::Paused);
+    context.GetEventBus().Publish(PlayModePausedEvent{});
+    return true;
+}
+
+} // namespace Editor
+} // namespace XCEngine