From 23b8fb197f4f81530bde6e8d9cac7eaed20a5b2b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Vondru=C5=A1?= <mosra@centrum.cz>
Date: Fri, 31 Dec 2010 16:03:58 +0100
Subject: [PATCH] Function for geting scene of an object.

Makes use of the fact that scene and only scene is parent of itself.
---
 src/Object.cpp          | 13 +++++++++++++
 src/Object.h            |  6 ++++++
 src/Test/ObjectTest.cpp | 14 ++++++++++++++
 src/Test/ObjectTest.h   |  1 +
 4 files changed, 34 insertions(+)

diff --git a/src/Object.cpp b/src/Object.cpp
index eb948d854..8ba541163 100644
--- a/src/Object.cpp
+++ b/src/Object.cpp
@@ -14,6 +14,7 @@
 */
 
 #include "Object.h"
+#include "Scene.h"
 
 using namespace std;
 
@@ -51,4 +52,16 @@ Object::~Object() {
         delete *it;
 }
 
+Scene* Object::scene() const {
+    /* Goes up the family tree until it finds object which is parent of itself
+       (that's the scene) */
+    Object* p = parent();
+    while(p != 0) {
+        if(p->parent() == p) return static_cast<Scene*>(p);
+        p = p->parent();
+    }
+
+    return 0;
+}
+
 }
diff --git a/src/Object.h b/src/Object.h
index 489a5b749..3f35eec74 100644
--- a/src/Object.h
+++ b/src/Object.h
@@ -57,6 +57,12 @@ class Object {
          */
         virtual ~Object();
 
+        /**
+         * @brief Scene
+         * @return If the object is not assigned to any scene, returns 0.
+         */
+        Scene* scene() const;
+
         /** @brief Parent object */
         inline Object* parent() const { return _parent; }
 
diff --git a/src/Test/ObjectTest.cpp b/src/Test/ObjectTest.cpp
index 12f02dca3..22a15959b 100644
--- a/src/Test/ObjectTest.cpp
+++ b/src/Test/ObjectTest.cpp
@@ -14,6 +14,7 @@
 */
 
 #include "ObjectTest.h"
+#include "Scene.h"
 
 #include <QtTest/QTest>
 
@@ -48,4 +49,17 @@ void ObjectTest::parenting() {
     QVERIFY(childOne->children().size() == 0);
 }
 
+void ObjectTest::scene() {
+    Scene scene;
+
+    Object* childOne = new Object(&scene);
+    Object* childTwo = new Object(childOne);
+
+    Object* orphan = new Object;
+    Object* childOfOrphan = new Object(orphan);
+
+    QVERIFY(childTwo->scene() == &scene);
+    QVERIFY(childOfOrphan->scene() == 0);
+}
+
 }}
diff --git a/src/Test/ObjectTest.h b/src/Test/ObjectTest.h
index 8e311d828..fccd4a903 100644
--- a/src/Test/ObjectTest.h
+++ b/src/Test/ObjectTest.h
@@ -26,6 +26,7 @@ class ObjectTest: public QObject {
 
     private slots:
         void parenting();
+        void scene();
 };
 
 }}