From 2c38e337ae78d620ec1af72f11b29efb59f6eb0d Mon Sep 17 00:00:00 2001
From: Andrei Kortunov <andrei.kortunov@yandex.ru>
Date: Wed, 23 Jan 2019 21:01:54 +0400
Subject: [PATCH] Support NiSwitchNode (feature #4812)

---
 CHANGELOG.md                       |  1 +
 components/nifosg/nifloader.cpp    | 25 +++++++++++++++++++++++++
 components/sceneutil/optimizer.cpp | 13 +++++++++++++
 components/sceneutil/optimizer.hpp |  2 ++
 4 files changed, 41 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0fda600fc..31e086842 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -26,6 +26,7 @@
     Feature #3610: Option to invert X axis
     Feature #4673: Weapon sheathing
     Feature #4730: Native animated containers support
+    Feature #4812: Support NiSwitchNode
     Task #4686: Upgrade media decoder to a more current FFmpeg API
 
 0.45.0
diff --git a/components/nifosg/nifloader.cpp b/components/nifosg/nifloader.cpp
index 08f6eb96c..0ed485862 100644
--- a/components/nifosg/nifloader.cpp
+++ b/components/nifosg/nifloader.cpp
@@ -5,6 +5,7 @@
 #include <osg/Geometry>
 #include <osg/Array>
 #include <osg/LOD>
+#include <osg/Switch>
 #include <osg/TexGen>
 #include <osg/ValueObject>
 
@@ -335,6 +336,13 @@ namespace NifOsg
             return lod;
         }
 
+        osg::ref_ptr<osg::Switch> handleSwitchNode(const Nif::NiSwitchNode* niSwitchNode)
+        {
+            osg::ref_ptr<osg::Switch> switchNode (new osg::Switch);
+            switchNode->setNewChildDefaultValue(false);
+            return switchNode;
+        }
+
         osg::ref_ptr<osg::Image> handleSourceTexture(const Nif::NiSourceTexture* st, Resource::ImageManager* imageManager)
         {
             if (!st)
@@ -593,6 +601,23 @@ namespace NifOsg
                 node = lod;
             }
 
+            if (nifNode->recType == Nif::RC_NiSwitchNode)
+            {
+                const Nif::NiSwitchNode* niSwitchNode = static_cast<const Nif::NiSwitchNode*>(nifNode);
+                osg::ref_ptr<osg::Switch> switchNode = handleSwitchNode(niSwitchNode);
+                node->addChild(switchNode);
+                const Nif::NodeList &children = niSwitchNode->children;
+                for(size_t i = 0;i < children.length();++i)
+                {
+                    if(!children[i].empty())
+                        handleNode(children[i].getPtr(), switchNode, imageManager, boundTextures, animflags, skipMeshes, hasMarkers, isAnimated, textKeys, rootNode);
+                }
+
+                // show only first child by default
+                switchNode->setSingleChildOn(0);
+                return switchNode;
+            }
+
             const Nif::NiNode *ninode = dynamic_cast<const Nif::NiNode*>(nifNode);
             if(ninode)
             {
diff --git a/components/sceneutil/optimizer.cpp b/components/sceneutil/optimizer.cpp
index 5d50c369d..f2717fea2 100644
--- a/components/sceneutil/optimizer.cpp
+++ b/components/sceneutil/optimizer.cpp
@@ -807,6 +807,13 @@ void Optimizer::RemoveRedundantNodesVisitor::apply(osg::LOD& lod)
         traverse(*lod.getChild(i));
 }
 
+void Optimizer::RemoveRedundantNodesVisitor::apply(osg::Switch& switchNode)
+{
+    // We should keep all switch child nodes since they reflect different switch states.
+    for (unsigned int i=0; i<switchNode.getNumChildren(); ++i)
+        traverse(*switchNode.getChild(i));
+}
+
 void Optimizer::RemoveRedundantNodesVisitor::apply(osg::Group& group)
 {
     if (typeid(group)==typeid(osg::Group) &&
@@ -1862,6 +1869,12 @@ void Optimizer::MergeGroupsVisitor::apply(osg::LOD &lod)
     traverse(lod);
 }
 
+void Optimizer::MergeGroupsVisitor::apply(osg::Switch &switchNode)
+{
+    // We should keep all switch child nodes since they reflect different switch states.
+    traverse(switchNode);
+}
+
 void Optimizer::MergeGroupsVisitor::apply(osg::Group &group)
 {
     if (group.getNumChildren() <= 1)
diff --git a/components/sceneutil/optimizer.hpp b/components/sceneutil/optimizer.hpp
index 1e4ffb342..6dd4394d1 100644
--- a/components/sceneutil/optimizer.hpp
+++ b/components/sceneutil/optimizer.hpp
@@ -340,6 +340,7 @@ class Optimizer
                 virtual void apply(osg::Group& group);
                 virtual void apply(osg::Transform& transform);
                 virtual void apply(osg::LOD& lod);
+                virtual void apply(osg::Switch& switchNode);
 
                 bool isOperationPermissible(osg::Node& node);
 
@@ -360,6 +361,7 @@ class Optimizer
 
             virtual void apply(osg::Group& group);
             virtual void apply(osg::LOD& lod);
+            virtual void apply(osg::Switch& switchNode);
         };
 
         class MergeGeometryVisitor : public BaseOptimizerVisitor