From a369c26a280d2226b82f4ae510701c823aec69e6 Mon Sep 17 00:00:00 2001
From: stiffly <adambylehn@hotmail.com>
Date: Mon, 7 Mar 2016 14:19:22 +0100
Subject: [PATCH] Blend tree nodes can now exist without transform components,
 without the game crashing.

---
 include/Engine/Editor/EditorSystem.h |  1 +
 src/Engine/Editor/EditorSystem.cpp   | 24 +++++++++++++++++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/include/Engine/Editor/EditorSystem.h b/include/Engine/Editor/EditorSystem.h
index 655ac9b9..a6d3e759 100644
--- a/include/Engine/Editor/EditorSystem.h
+++ b/include/Engine/Editor/EditorSystem.h
@@ -47,6 +47,7 @@ private:
     // Utility functions
     EntityWrapper importEntity(EntityWrapper parent, boost::filesystem::path filePath);
     void setWidgetMode(EditorGUI::WidgetMode mode);
+    bool IsAnyParentMissingTransform(EntityID entityID);
 
     // GUI callbacks
     void OnEntitySelected(EntityWrapper entity);
diff --git a/src/Engine/Editor/EditorSystem.cpp b/src/Engine/Editor/EditorSystem.cpp
index f9cdde0b..f66cd01c 100644
--- a/src/Engine/Editor/EditorSystem.cpp
+++ b/src/Engine/Editor/EditorSystem.cpp
@@ -4,7 +4,7 @@
 #include "Editor/EditorWidgetSystem.h"
 #include "Core/EntityFile.h"
 
-EditorSystem::EditorSystem(SystemParams params, IRenderer* renderer, RenderFrame* renderFrame) 
+EditorSystem::EditorSystem(SystemParams params, IRenderer* renderer, RenderFrame* renderFrame)
     : System(params)
     , m_Renderer(renderer)
     , m_RenderFrame(renderFrame)
@@ -14,7 +14,7 @@ EditorSystem::EditorSystem(SystemParams params, IRenderer* renderer, RenderFrame
     m_EditorWorldSystemPipeline->AddSystem<UniformScaleSystem>(0);
     m_EditorWorldSystemPipeline->AddSystem<EditorWidgetSystem>(0, m_Renderer);
     m_EditorWorldSystemPipeline->AddSystem<EditorRenderSystem>(1, m_Renderer, m_RenderFrame);
-    
+
     m_EditorCamera = importEntity(EntityWrapper(m_EditorWorld, EntityID_Invalid), "Schema/Entities/Empty.xml");
     m_ActualCamera = m_EditorCamera;
     m_EditorWorld->AttachComponent(m_EditorCamera.ID, "Transform");
@@ -70,7 +70,11 @@ void EditorSystem::Update(double dt)
         m_EditorGUI->Draw();
         m_EditorStats->Draw(actualDelta);
 
+        if (IsAnyParentMissingTransform(m_CurrentSelection.ID)) {
+            return;
+        }
         if (m_CurrentSelection.Valid() && m_Widget.Valid()) {
+
             (glm::vec3&)m_Widget["Transform"]["Position"] = Transform::AbsolutePosition(m_CurrentSelection);
             if (m_WidgetSpace == EditorGUI::WidgetSpace::Local) {
                 (glm::vec3&)m_Widget["Transform"]["Orientation"] = Transform::AbsoluteOrientationEuler(m_CurrentSelection);
@@ -78,7 +82,6 @@ void EditorSystem::Update(double dt)
                 (glm::vec3&)m_Widget["Transform"]["Orientation"] = glm::vec3(0, 0, 0);
             }
         }
-
         m_EditorWorldSystemPipeline->Update(actualDelta);
 
         ComponentWrapper& cameraTransform = m_EditorCamera["Transform"];
@@ -202,6 +205,9 @@ bool EditorSystem::OnMousePress(const Events::MousePress& e)
 bool EditorSystem::OnWidgetDelta(const Events::WidgetDelta& e)
 {
     if (m_CurrentSelection.Valid()) {
+        if (IsAnyParentMissingTransform(m_CurrentSelection.ID)) {
+            return false;
+        }
         if (m_WidgetSpace == EditorGUI::WidgetSpace::Global) {
             glm::quat parentOrientation;
             EntityWrapper parent = m_CurrentSelection.Parent();
@@ -301,3 +307,15 @@ void EditorSystem::setWidgetMode(EditorGUI::WidgetMode mode)
 
     m_Widget["Transform"]["Position"] = Transform::AbsolutePosition(m_CurrentSelection.World, m_CurrentSelection.ID);
 }
+
+bool EditorSystem::IsAnyParentMissingTransform(EntityID entityID)
+{
+    EntityWrapper entity(m_World, entityID);
+    while (entity.Parent().Valid()) {
+        if (!entity.HasComponent("Transform")) {
+            return true;
+        }
+        entity = entity.Parent();
+    }
+    return false;
+}