Added mouse relative mode

chalonverse · chalonverse · commit b8d57c250379 · 2017-11-29T13:34:17.000-08:00
diff --git a/Chapter08/InputSystem.cpp b/Chapter08/InputSystem.cpp
@@ -102,13 +102,32 @@ void InputSystem::PrepareForUpdate()
 
 	// Mouse
 	mState.Mouse.mPrevButtons = mState.Mouse.mCurrButtons;
+	mState.Mouse.mIsRelative = false;
 }
 
 void InputSystem::Update()
 {
 	// Mouse
 	int x = 0, y = 0;
-	mState.Mouse.mCurrButtons = SDL_GetMouseState(&x, &y);
+	if (mState.Mouse.mIsRelative)
+	{
+		mState.Mouse.mCurrButtons = 
+			SDL_GetRelativeMouseState(&x, &y);
+	}
+	else
+	{
+		mState.Mouse.mCurrButtons = 
+			SDL_GetMouseState(&x, &y);
+	}
+
 	mState.Mouse.mMousePos.x = static_cast<float>(x);
 	mState.Mouse.mMousePos.y = static_cast<float>(y);
 }
+
+void InputSystem::SetRelativeMouseMode(bool value)
+{
+	SDL_bool set = value ? SDL_TRUE : SDL_FALSE;
+	SDL_SetRelativeMouseMode(set);
+
+	mState.Mouse.mIsRelative = value;
+}
diff --git a/Chapter08/InputSystem.h b/Chapter08/InputSystem.h
@@ -42,6 +42,7 @@ class MouseState
 
 	// For mouse position
 	const Vector2& GetPosition() const { return mMousePos; }
+	bool IsRelative() const { return mIsRelative; }
 
 	// For buttons
 	bool GetButtonValue(int button) const;
@@ -52,6 +53,8 @@ class MouseState
 	// Store button data
 	Uint32 mCurrButtons;
 	Uint32 mPrevButtons;
+	// Are we in relative mouse mode
+	bool mIsRelative;
 };
 
 // Wrapper that contains current state of input
@@ -73,6 +76,8 @@ class InputSystem
 	void Update();
 
 	const InputState& GetState() const { return mState; }
+
+	void SetRelativeMouseMode(bool value);
 private:
 	InputState mState;
 };
