Scene nodes now persist their order.

Implemented error handling and insertion logic for KRContext::createNode
Refactored KRNode::m_childNodes to be a std::list rather than a std::set
Added stub function, KRNode::createNode, which accepts a KrCreateNodeInfo structure

kraken/KRContext.cpp

@@ -753,19 +753,71 @@ KrResult KRContext::deleteNodeChildren(const KrDeleteNodeChildrenInfo* pDeleteNo
 
 KrResult KRContext::createNode(const KrCreateNodeInfo* pCreateNodeInfo)
 {
+  if (pCreateNodeInfo->sceneHandle < 0 || pCreateNodeInfo->sceneHandle >= m_resourceMapSize) {
+    return KR_ERROR_OUT_OF_BOUNDS;
+  }
+  KRResource* sceneResource = m_resourceMap[pCreateNodeInfo->sceneHandle];
+  if (sceneResource == nullptr) {
+    return KR_ERROR_NOT_MAPPED;
+  }
+  KRScene* scene = dynamic_cast<KRScene*>(sceneResource);
+  if (scene == nullptr) {
+    return KR_ERROR_INCORRECT_TYPE;
+  }
   if (pCreateNodeInfo->newNodeHandle < 0 || pCreateNodeInfo->newNodeHandle >= m_nodeMapSize) {
     return KR_ERROR_OUT_OF_BOUNDS;
   }
   if (pCreateNodeInfo->relativeNodeHandle < 0 || pCreateNodeInfo->relativeNodeHandle >= m_nodeMapSize) {
     return KR_ERROR_OUT_OF_BOUNDS;
   }
+  if (pCreateNodeInfo->location < 0 || pCreateNodeInfo->location >= KR_SCENE_NODE_INSERT_MAX_ENUM) {
+    return KR_ERROR_OUT_OF_BOUNDS;
+  }
   KRNode* relativeNode = nullptr;
-  if (pCreateNodeInfo->relativeNodeHandle != KR_NULL_HANDLE) {
+  if (pCreateNodeInfo->relativeNodeHandle == KR_NULL_HANDLE) {
+    relativeNode = scene->getRootNode();
+  } else {
     // TODO - Handle node deletions by deleting nodes from m_nodeMap
     relativeNode = m_nodeMap[pCreateNodeInfo->relativeNodeHandle];
+    if (relativeNode == nullptr) {
+      return KR_ERROR_NOT_FOUND;
+    }
   }
 
+  if (pCreateNodeInfo->location == KR_SCENE_NODE_INSERT_BEFORE ||
+    pCreateNodeInfo->location == KR_SCENE_NODE_INSERT_AFTER) {
+    // There can only be one root node
+    if (relativeNode->getParent() == nullptr) {
+      return KR_ERROR_UNEXPECTED;
+    }
+  }
+
+  KRNode* newNode = nullptr;
+  KrResult res = KRNode::createNode(pCreateNodeInfo, &newNode);
+  if (res != KR_SUCCESS) {
+    return res;
+  }
+
+  if (relativeNode) {
+    switch (pCreateNodeInfo->location) {
+    case KR_SCENE_NODE_INSERT_BEFORE:
+      relativeNode->insertBefore(newNode);
+      break;
+    case KR_SCENE_NODE_INSERT_AFTER:
+      relativeNode->insertAfter(newNode);
+      break;
+    case KR_SCENE_NODE_PREPEND_CHILD:
+      relativeNode->prependChild(newNode);
+      break;
+    case KR_SCENE_NODE_APPEND_CHILD:
+      relativeNode->appendChild(newNode);
+      break;
+    default:
+      assert(false);
       return KR_ERROR_NOT_IMPLEMENTED;
+    }
+  }
+  return KR_SUCCESS;
 }
 
 KrResult KRContext::updateNode(const KrUpdateNodeInfo* pUpdateNodeInfo)

kraken/KRLODSet.cpp

@@ -75,7 +75,7 @@ void KRLODSet::updateLODVisibility(const KRViewport& viewport)
     */
 
     // Upgrade and downgrade LOD groups as needed
-    for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+    for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
       KRLODGroup* lod_group = dynamic_cast<KRLODGroup*>(*itr);
       assert(lod_group != NULL);
       LodVisibility group_lod_visibility = KRMIN(lod_group->calcLODVisibility(viewport), m_lod_visible);
@@ -101,7 +101,7 @@ void KRLODSet::updateLODVisibility(const KRViewport& viewport)
 
     if (streamer_ready) {
       // Upgrade and downgrade LOD groups as needed
-      for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+      for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
         KRLODGroup* lod_group = dynamic_cast<KRLODGroup*>(*itr);
         assert(lod_group != NULL);
         LodVisibility group_lod_visibility = KRMIN(lod_group->calcLODVisibility(viewport), m_lod_visible);
@@ -131,7 +131,7 @@ kraken_stream_level KRLODSet::getStreamLevel(const KRViewport& viewport)
   KRLODGroup* new_active_lod_group = NULL;
 
   // Upgrade and downgrade LOD groups as needed
-  for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+  for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
     KRLODGroup* lod_group = dynamic_cast<KRLODGroup*>(*itr);
     assert(lod_group != NULL);
     if (lod_group->calcLODVisibility(viewport) == LOD_VISIBILITY_VISIBLE) {

kraken/KRNode.cpp

@@ -145,16 +145,52 @@ bool KRNode::getScaleCompensation()
 
 void KRNode::childDeleted(KRNode* child_node)
 {
-  m_childNodes.erase(child_node);
+  // TODO - We should give KRNode's linked list pointers directly and eliminate m_childNodes so that we don't need
+  // to perform slow std::find operations like this one.
+  // TODO - FIXME - This is a slow operation...
+  std::list<KRNode*>::iterator itr = std::find(m_childNodes.begin(), m_childNodes.end(), child_node);
+  if (itr != m_childNodes.end()) {
+    m_childNodes.erase(itr);
+  }
   invalidateBounds();
   getScene().notify_sceneGraphModify(this);
 }
 
-void KRNode::addChild(KRNode* child)
+void KRNode::appendChild(KRNode* child)
 {
   assert(child->m_parentNode == NULL);
   child->m_parentNode = this;
-  m_childNodes.insert(child);
+  m_childNodes.push_back(child);
+  child->setLODVisibility(m_lod_visible); // Child node inherits LOD visibility status from parent
+}
+
+void KRNode::prependChild(KRNode* child)
+{
+  assert(child->m_parentNode == NULL);
+  child->m_parentNode = this;
+  m_childNodes.push_front(child);
+  child->setLODVisibility(m_lod_visible); // Child node inherits LOD visibility status from parent
+}
+void KRNode::insertBefore(KRNode* child)
+{
+  assert(m_parentNode != NULL); // There can only be one root node
+  assert(child->m_parentNode == NULL);
+  child->m_parentNode = m_parentNode;
+  std::list<KRNode*>::iterator itr = std::find(m_parentNode->m_childNodes.begin(), m_parentNode->m_childNodes.end(), this);
+  assert(itr != m_parentNode->m_childNodes.end());
+
+  m_parentNode->m_childNodes.insert(itr, child);
+  child->setLODVisibility(m_lod_visible); // Child node inherits LOD visibility status from parent
+}
+void KRNode::insertAfter(KRNode* child)
+{
+  assert(m_parentNode != NULL); // There can only be one root node
+  assert(child->m_parentNode == NULL);
+  child->m_parentNode = m_parentNode;
+  std::list<KRNode*>::iterator itr = std::find(m_parentNode->m_childNodes.begin(), m_parentNode->m_childNodes.end(), this);
+  assert(itr != m_parentNode->m_childNodes.end());
+  itr++;
+  m_parentNode->m_childNodes.insert(itr, child);
   child->setLODVisibility(m_lod_visible); // Child node inherits LOD visibility status from parent
 }
 
@@ -174,13 +210,18 @@ tinyxml2::XMLElement* KRNode::saveXML(tinyxml2::XMLNode* parent)
   kraken::setXMLAttribute("pre_rotate", e, (m_preRotation * (180.0f / (float)M_PI)), Vector3::Zero());
   kraken::setXMLAttribute("post_rotate", e, (m_postRotation * (180.0f / (float)M_PI)), Vector3::Zero());
 
-  for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+  for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
     KRNode* child = (*itr);
     child->saveXML(n);
   }
   return e;
 }
 
+KrResult KRNode::createNode(const KrCreateNodeInfo* pCreateNodeInfo, KRNode** node)
+{
+  return KR_ERROR_NOT_IMPLEMENTED;
+}
+
 void KRNode::loadXML(tinyxml2::XMLElement* e)
 {
   m_name = e->Attribute("name");
@@ -227,7 +268,7 @@ void KRNode::loadXML(tinyxml2::XMLElement* e)
       KRNode* child_node = KRNode::LoadXML(getScene(), child_element);
 
       if (child_node) {
-        addChild(child_node);
+        appendChild(child_node);
       }
     }
   }
@@ -515,7 +556,7 @@ void KRNode::render(const RenderInfo& ri)
   m_lastRenderFrame = getContext().getCurrentFrame();
 }
 
-const std::set<KRNode*>& KRNode::getChildren()
+const std::list<KRNode*>& KRNode::getChildren()
 {
   return m_childNodes;
 }
@@ -541,7 +582,7 @@ AABB KRNode::getBounds()
     AABB bounds = AABB::Zero();
 
     bool first_child = true;
-    for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+    for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
       KRNode* child = (*itr);
       if (child->getBounds() != AABB::Zero()) {
         if (first_child) {
@@ -564,7 +605,7 @@ void KRNode::invalidateModelMatrix()
   m_modelMatrixValid = false;
   m_activePoseMatrixValid = false;
   m_inverseModelMatrixValid = false;
-  for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+  for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
     KRNode* child = (*itr);
     child->invalidateModelMatrix();
   }
@@ -577,7 +618,7 @@ void KRNode::invalidateBindPoseMatrix()
 {
   m_bindPoseMatrixValid = false;
   m_inverseBindPoseMatrixValid = false;
-  for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+  for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
     KRNode* child = (*itr);
     child->invalidateBindPoseMatrix();
   }
@@ -956,7 +997,7 @@ void KRNode::addToOctreeNode(KROctreeNode* octree_node)
 void KRNode::updateLODVisibility(const KRViewport& viewport)
 {
   if (m_lod_visible >= LOD_VISIBILITY_PRESTREAM) {
-    for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+    for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
       (*itr)->updateLODVisibility(viewport);
     }
   }
@@ -973,7 +1014,7 @@ void KRNode::setLODVisibility(KRNode::LodVisibility lod_visibility)
 
     m_lod_visible = lod_visibility;
 
-    for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+    for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
       (*itr)->setLODVisibility(lod_visibility);
     }
   }
@@ -1010,7 +1051,7 @@ kraken_stream_level KRNode::getStreamLevel(const KRViewport& viewport)
 {
   kraken_stream_level stream_level = kraken_stream_level::STREAM_LEVEL_IN_HQ;
 
-  for (std::set<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+  for (std::list<KRNode*>::iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
     stream_level = KRMIN(stream_level, (*itr)->getStreamLevel(viewport));
   }
 

kraken/KRNode.h

@@ -115,13 +115,17 @@ public:
   virtual tinyxml2::XMLElement* saveXML(tinyxml2::XMLNode* parent);
 
   static KRNode* LoadXML(KRScene& scene, tinyxml2::XMLElement* e);
+  static KrResult createNode(const KrCreateNodeInfo* pCreateNodeInfo, KRNode** node);
   virtual void loadXML(tinyxml2::XMLElement* e);
 
   virtual std::string getElementName();
   const std::string& getName() const;
 
-  void addChild(KRNode* child);
+  void appendChild(KRNode* child);
-  const std::set<KRNode*>& getChildren();
+  void prependChild(KRNode* child);
+  void insertBefore(KRNode* child);
+  void insertAfter(KRNode* child);
+  const std::list<KRNode*>& getChildren();
   KRNode* getParent();
 
   void setLocalTranslation(const Vector3& v, bool set_original = false);
@@ -262,7 +266,7 @@ protected:
   LodVisibility m_lod_visible;
 
   KRNode* m_parentNode;
-  std::set<KRNode*> m_childNodes;
+  std::list<KRNode*> m_childNodes;
 
   bool m_animation_mask[KRENGINE_NODE_ATTRIBUTE_COUNT];
 
@@ -319,7 +323,7 @@ public:
       return match;
     }
 
-    for (std::set<KRNode*>::const_iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+    for (std::list<KRNode*>::const_iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
       match = (*itr)->find<T>();
       if (match) {
         return match;
@@ -338,7 +342,7 @@ public:
       }
     }
 
-    for (std::set<KRNode*>::const_iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
+    for (std::list<KRNode*>::const_iterator itr = m_childNodes.begin(); itr != m_childNodes.end(); ++itr) {
       match = (*itr)->find<T>(name);
       if (match) {
         return match;

kraken/KRResource+fbx.cpp

@@ -966,7 +966,7 @@ void LoadNode(FbxScene* pFbxScene, KRNode* parent_node, FbxGeometryConverter* pG
     }
 
     KRLODSet* lod_set = new KRLODSet(parent_node->getScene(), name);
-    parent_node->addChild(lod_set);
+    parent_node->appendChild(lod_set);
 
     AABB reference_bounds;
     // Create a lod_group node for each fbx child node
@@ -1026,7 +1026,7 @@ void LoadNode(FbxScene* pFbxScene, KRNode* parent_node, FbxGeometryConverter* pG
       new_node->setPostRotation(node_post_rotation);
 
       new_node->setUseWorldUnits(use_world_space_units);
-      lod_set->addChild(new_node);
+      lod_set->appendChild(new_node);
 
       LoadNode(pFbxScene, new_node, pGeometryConverter, pNode->GetChild(i));
 
@@ -1087,7 +1087,7 @@ void LoadNode(FbxScene* pFbxScene, KRNode* parent_node, FbxGeometryConverter* pG
       new_node->setScalingPivot(node_scaling_pivot);
       new_node->setPreRotation(node_pre_rotation);
       new_node->setPostRotation(node_post_rotation);
-      parent_node->addChild(new_node);
+      parent_node->appendChild(new_node);
 
       // Load child nodes
       for (int i = 0; i < pNode->GetChildCount(); i++) {

kraken/KRScene.cpp

@@ -62,7 +62,7 @@ void KRScene::renderFrame(VkCommandBuffer& commandBuffer, KRSurface& surface, fl
   if (camera == NULL) {
     // Add a default camera if none are present
     camera = new KRCamera(*this, "default_camera");
-    m_pRootNode->addChild(camera);
+    m_pRootNode->appendChild(camera);
   }
 
   // FINDME - This should be moved to de-couple Siren from the Rendering pipeline
@@ -409,7 +409,7 @@ KRScene* KRScene::Load(KRContext& context, const std::string& name, KRDataBlock*
 
   KRNode* n = KRNode::LoadXML(*new_scene, scene_element->FirstChildElement());
   if (n) {
-    new_scene->getRootNode()->addChild(n);
+    new_scene->getRootNode()->appendChild(n);
   }
 
 
@@ -554,7 +554,7 @@ void KRScene::addDefaultLights()
   KRDirectionalLight* light1 = new KRDirectionalLight(*this, "default_light1");
 
   light1->setLocalRotation((Quaternion::Create(Vector3::Create(0.0f, (float)M_PI * 0.10f, 0.0f)) * Quaternion::Create(Vector3::Create(0.0f, 0.0f, (float)-M_PI * 0.15f))).eulerXYZ());
-  m_pRootNode->addChild(light1);
+  m_pRootNode->appendChild(light1);
 }
 
 AABB KRScene::getRootOctreeBounds()

kraken/public/kraken.h

@@ -109,10 +109,11 @@ typedef enum
 
 typedef enum
 {
-  KR_SCENE_NODE_INSERT_BEFORE,
+  KR_SCENE_NODE_INSERT_BEFORE = 0,
   KR_SCENE_NODE_INSERT_AFTER,
-  KR_SCENE_NODE_INSERT_FIRST_CHILD,
+  KR_SCENE_NODE_PREPEND_CHILD,
-  KR_SCENE_NODE_INSERT_LAST_CHILD,
+  KR_SCENE_NODE_APPEND_CHILD,
+  KR_SCENE_NODE_INSERT_MAX_ENUM
 } KrSceneNodeInsertLocation;
 
 typedef int KrResourceMapIndex;

tests/smoke/hello_cube/hello_cube.cpp

@@ -65,7 +65,8 @@ void smoke_load()
   KrCreateNodeInfo create_camera_info = { KR_STRUCTURE_TYPE_CREATE_NODE };
   res = KrInitNodeInfo(&create_camera_info.node, KR_STRUCTURE_TYPE_NODE_CAMERA);
   assert(res == KR_SUCCESS);
-  create_camera_info.relativeNodeHandle = -1;
+  create_camera_info.relativeNodeHandle = KR_NULL_HANDLE;
+  create_camera_info.location = KR_SCENE_NODE_APPEND_CHILD;
   create_camera_info.newNodeHandle = kCameraNodeHandle;
   create_camera_info.sceneHandle = kSceneResourceHandle;
   create_camera_info.node.pName = "my_camera";