From 1d198a5592e0d4d6f3a4d0b7388d87f5e29b3482 Mon Sep 17 00:00:00 2001
From: scrawl <scrawl@baseoftrash.de>
Date: Mon, 15 Jun 2015 18:09:01 +0200
Subject: [PATCH] Keep the light list StateSet cache for more than one frame

---
 components/sceneutil/lightmanager.cpp | 23 +++++++++++++++--------
 components/sceneutil/lightmanager.hpp | 17 +++++++++--------
 2 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/components/sceneutil/lightmanager.cpp b/components/sceneutil/lightmanager.cpp
index 6040f9536..65955d9af 100644
--- a/components/sceneutil/lightmanager.cpp
+++ b/components/sceneutil/lightmanager.cpp
@@ -145,7 +145,6 @@ namespace SceneUtil
     {
         mLightsInViewSpace = false;
         mLights.clear();
-        mStateSetCache.clear();
     }
 
     void LightManager::addLight(LightSource* lightSource, osg::Matrix worldMat)
@@ -180,7 +179,7 @@ namespace SceneUtil
         // possible optimization: return a StateSet containing all requested lights plus some extra lights (if a suitable one exists)
         size_t hash = 0;
         for (unsigned int i=0; i<lightList.size();++i)
-            boost::hash_combine(hash, lightList[i]);
+            boost::hash_combine(hash, lightList[i]->getId());
 
         LightStateSetMap::iterator found = mStateSetCache.find(hash);
         if (found != mStateSetCache.end())
@@ -190,10 +189,7 @@ namespace SceneUtil
 
             std::vector<osg::ref_ptr<osg::Light> > lights;
             for (unsigned int i=0; i<lightList.size();++i)
-            {
-                const LightSourceTransform& l = mLights[lightList[i]];
-                lights.push_back(l.mLightSource->getLight());
-            }
+                lights.push_back(lightList[i]->getLight());
 
             osg::ref_ptr<LightStateAttribute> attr = new LightStateAttribute(mStartLight, lights);
 
@@ -223,11 +219,22 @@ namespace SceneUtil
         return mStartLight;
     }
 
+    static int sLightId = 0;
+
     LightSource::LightSource()
         : mRadius(0.f)
     {
         setNodeMask(Mask_Lit);
         setUpdateCallback(new CollectLightCallback);
+        mId = sLightId++;
+    }
+
+    LightSource::LightSource(const LightSource &copy, const osg::CopyOp &copyop)
+        : osg::Node(copy, copyop)
+        , mLight(copy.mLight)
+        , mRadius(copy.mRadius)
+    {
+        mId = sLightId++;
     }
 
     void LightListCallback::operator()(osg::Node *node, osg::NodeVisitor *nv)
@@ -282,12 +289,12 @@ namespace SceneUtil
                 osg::Matrixf mat = *cv->getModelViewMatrix();
                 transformBoundingSphere(mat, nodeBound);
 
-                std::vector<int> lightList;
+                std::vector<LightSource*> lightList;
                 for (unsigned int i=0; i<lights.size(); ++i)
                 {
                     const LightManager::LightSourceTransform& l = lights[i];
                     if (l.mViewBound.intersects(nodeBound))
-                        lightList.push_back(i);
+                        lightList.push_back(l.mLightSource);
                 }
 
                 if (lightList.empty())
diff --git a/components/sceneutil/lightmanager.hpp b/components/sceneutil/lightmanager.hpp
index d5aecdbb6..ac819958f 100644
--- a/components/sceneutil/lightmanager.hpp
+++ b/components/sceneutil/lightmanager.hpp
@@ -20,18 +20,15 @@ namespace SceneUtil
         // The activation radius
         float mRadius;
 
+        int mId;
+
     public:
 
         META_Node(SceneUtil, SceneUtil::LightSource)
 
         LightSource();
 
-        LightSource(const LightSource& copy, const osg::CopyOp& copyop)
-            : osg::Node(copy, copyop)
-            , mLight(copy.mLight)
-            , mRadius(copy.mRadius)
-        {
-        }
+        LightSource(const LightSource& copy, const osg::CopyOp& copyop);
 
         float getRadius() const
         {
@@ -52,6 +49,11 @@ namespace SceneUtil
         {
             mLight = light;
         }
+
+        int getId()
+        {
+            return mId;
+        }
     };
 
     /// All light sources must be a child of the LightManager node. The LightManager can be anywhere in the scene graph,
@@ -83,8 +85,7 @@ namespace SceneUtil
 
         const std::vector<LightSourceTransform>& getLights() const;
 
-        // Stores indices into the mLights vector
-        typedef std::vector<int> LightList;
+        typedef std::vector<LightSource*> LightList;
 
         osg::ref_ptr<osg::StateSet> getLightListStateSet(const LightList& lightList);