Place Drawables directly in the scene graph when built with OSG 3.4

OSG 3.4 adds the ability to place Drawables directly in the scene graph, without a Geode decorating them. Leveraging this should give a small performance boost, because the redundant Geodes increase culling overhead.

There is still an oustanding issue with the RemoveDrawableVisitor no longer working correctly, because Drawables can have multiple parents.

apps/openmw/mwrender/animation.cpp

@@ -11,6 +11,7 @@
 #include <osg/Geode>
 #include <osg/BlendFunc>
 #include <osg/Material>
+#include <osg/Version>
 
 #include <osgParticle/ParticleSystem>
 
@@ -196,10 +197,18 @@ namespace
             traverse(node);
         }
 
+#if OSG_VERSION_GREATER_OR_EQUAL(3,3,3)
+        virtual void apply(osg::Drawable& drw)
+        {
+            mToRemove.push_back(&drw);
+        }
+#endif
+
         void remove()
         {
             for (std::vector<osg::Node*>::iterator it = mToRemove.begin(); it != mToRemove.end(); ++it)
             {
+                // FIXME: a Drawable might have more than one parent
                 osg::Node* node = *it;
                 if (node->getNumParents())
                     node->getParent(0)->removeChild(node);
@@ -219,6 +228,18 @@ namespace
         }
 
         virtual void apply(osg::Geode &node)
+        {
+            applyImpl(node);
+        }
+
+#if OSG_VERSION_GREATER_OR_EQUAL(3,3,3)
+        virtual void apply(osg::Drawable& drw)
+        {
+            applyImpl(drw);
+        }
+#endif
+
+        void applyImpl(osg::Node& node)
         {
             const std::string toFind = "tri bip";
             if (Misc::StringUtils::ciCompareLen(node.getName(), toFind, toFind.size()) == 0)
@@ -232,6 +253,7 @@ namespace
         {
             for (std::vector<osg::Node*>::iterator it = mToRemove.begin(); it != mToRemove.end(); ++it)
             {
+                // FIXME: a Drawable might have more than one parent
                 osg::Node* node = *it;
                 if (node->getNumParents())
                     node->getParent(0)->removeChild(node);

apps/openmw/mwrender/objects.cpp

@@ -6,6 +6,7 @@
 #include <osg/Geode>
 #include <osg/PositionAttitudeTransform>
 #include <osg/UserDataContainer>
+#include <osg/Version>
 
 #include <osgParticle/ParticleSystem>
 #include <osgParticle/ParticleProcessor>
@@ -54,11 +55,19 @@ namespace
             for (std::vector<osgParticle::ParticleSystem*>::iterator it = partsysVector.begin(); it != partsysVector.end(); ++it)
                 geode.removeDrawable(*it);
         }
+#if OSG_VERSION_GREATER_OR_EQUAL(3,3,3)
+        virtual void apply(osg::Drawable& drw)
+        {
+            if (osgParticle::ParticleSystem* partsys = dynamic_cast<osgParticle::ParticleSystem*>(&drw))
+                mToRemove.push_back(partsys);
+        }
+#endif
 
         void remove()
         {
             for (std::vector<osg::ref_ptr<osg::Node> >::iterator it = mToRemove.begin(); it != mToRemove.end(); ++it)
             {
+                // FIXME: a Drawable might have more than one parent
                 osg::Node* node = *it;
                 if (node->getNumParents())
                     node->getParent(0)->removeChild(node);

apps/openmw/mwrender/sky.cpp

@@ -351,33 +351,36 @@ public:
         for (unsigned int i=0; i<geode.getNumDrawables(); ++i)
         {
             osg::Drawable* drw = geode.getDrawable(i);
+            apply(*drw);
+        }
+    }
+    void apply(osg::Drawable& drw)
+    {
+        osg::Geometry* geom = drw.asGeometry();
+        if (!geom)
+            return;
 
-            osg::Geometry* geom = drw->asGeometry();
-            if (!geom)
-                continue;
-
-            osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array(geom->getVertexArray()->getNumElements());
-            for (unsigned int i=0; i<colors->size(); ++i)
+        osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array(geom->getVertexArray()->getNumElements());
+        for (unsigned int i=0; i<colors->size(); ++i)
+        {
+            float alpha = 1.f;
+            if (mMeshType == 0) alpha = i%2 ? 0.f : 1.f; // this is a cylinder, so every second vertex belongs to the bottom-most row
+            else if (mMeshType == 1)
             {
-                float alpha = 1.f;
-                if (mMeshType == 0) alpha = i%2 ? 0.f : 1.f; // this is a cylinder, so every second vertex belongs to the bottom-most row
-                else if (mMeshType == 1)
-                {
-                    if (i>= 49 && i <= 64) alpha = 0.f; // bottom-most row
-                    else if (i>= 33 && i <= 48) alpha = 0.25098; // second row
-                    else alpha = 1.f;
-                }
-                else if (mMeshType == 2)
-                {
-                    osg::Vec4Array* origColors = static_cast<osg::Vec4Array*>(geom->getColorArray());
-                    alpha = ((*origColors)[i].x() == 1.f) ? 1.f : 0.f;
-                }
-
-                (*colors)[i] = osg::Vec4f(0.f, 0.f, 0.f, alpha);
+                if (i>= 49 && i <= 64) alpha = 0.f; // bottom-most row
+                else if (i>= 33 && i <= 48) alpha = 0.25098; // second row
+                else alpha = 1.f;
+            }
+            else if (mMeshType == 2)
+            {
+                osg::Vec4Array* origColors = static_cast<osg::Vec4Array*>(geom->getColorArray());
+                alpha = ((*origColors)[i].x() == 1.f) ? 1.f : 0.f;
             }
 
-            geom->setColorArray(colors, osg::Array::BIND_PER_VERTEX);
+            (*colors)[i] = osg::Vec4f(0.f, 0.f, 0.f, alpha);
         }
+
+        geom->setColorArray(colors, osg::Array::BIND_PER_VERTEX);
     }
 
 private:

components/nifosg/nifloader.cpp

@@ -5,6 +5,7 @@
 #include <osg/Geode>
 #include <osg/Geometry>
 #include <osg/Array>
+#include <osg/Version>
 
 // resource
 #include <components/misc/stringops.hpp>
@@ -885,9 +886,6 @@ namespace NifOsg
             // localToWorldMatrix for transforming to particle space
             handleParticlePrograms(partctrl->affectors, partctrl->colliders, parentNode, partsys.get(), rf);
 
-            osg::ref_ptr<osg::Geode> geode (new osg::Geode);
-            geode->addDrawable(partsys);
-
             std::vector<const Nif::Property*> drawableProps;
             collectDrawableProperties(nifNode, drawableProps);
             applyDrawableProperties(parentNode, drawableProps, composite, true, animflags);
@@ -907,13 +905,21 @@ namespace NifOsg
             updater->addParticleSystem(partsys);
             parentNode->addChild(updater);
 
+#if not(OSG_MIN_VERSION_REQUIRED(3,3,3))
+            osg::ref_ptr<osg::Geode> geode (new osg::Geode);
+            geode->addDrawable(partsys);
+            osg::Node* toAttach = geode.get();
+#else
+            osg::Node* toAttach = partsys.get();
+#endif
+
             if (rf == osgParticle::ParticleProcessor::RELATIVE_RF)
-                parentNode->addChild(geode);
+                parentNode->addChild(toAttach);
             else
             {
                 osg::MatrixTransform* trans = new osg::MatrixTransform;
                 trans->setUpdateCallback(new InverseWorldMatrix);
-                trans->addChild(geode);
+                trans->addChild(toAttach);
                 parentNode->addChild(trans);
             }
         }
@@ -957,8 +963,6 @@ namespace NifOsg
 
         void handleTriShape(const Nif::NiTriShape* triShape, osg::Group* parentNode, SceneUtil::CompositeStateSetUpdater* composite, const std::vector<int>& boundTextures, int animflags)
         {
-            osg::ref_ptr<osg::Geode> geode (new osg::Geode);
-
             osg::ref_ptr<osg::Geometry> geometry;
             for (Nif::ControllerPtr ctrl = triShape->controller; !ctrl.empty(); ctrl = ctrl->next)
             {
@@ -981,21 +985,36 @@ namespace NifOsg
 
             triShapeToGeometry(triShape, geometry, parentNode, composite, boundTextures, animflags);
 
+#if not(OSG_MIN_VERSION_REQUIRED(3,3,3))
+            osg::ref_ptr<osg::Geode> geode (new osg::Geode);
             geode->addDrawable(geometry);
+#endif
 
             if (geometry->getDataVariance() == osg::Object::DYNAMIC)
             {
                 // Add a copy, we will alternate between the two copies every other frame using the FrameSwitch
                 // This is so we can set the DataVariance as STATIC, giving a huge performance boost
                 geometry->setDataVariance(osg::Object::STATIC);
-                osg::ref_ptr<osg::Geode> geode2 = static_cast<osg::Geode*>(osg::clone(geode.get(), osg::CopyOp::DEEP_COPY_NODES|osg::CopyOp::DEEP_COPY_DRAWABLES));
                 osg::ref_ptr<FrameSwitch> frameswitch = new FrameSwitch;
+
+#if not(OSG_MIN_VERSION_REQUIRED(3,3,3))
+                osg::ref_ptr<osg::Geode> geode2 = static_cast<osg::Geode*>(osg::clone(geode.get(), osg::CopyOp::DEEP_COPY_NODES|osg::CopyOp::DEEP_COPY_DRAWABLES));
                 frameswitch->addChild(geode);
                 frameswitch->addChild(geode2);
+#else
+                osg::ref_ptr<osg::Geometry> geom2 = static_cast<osg::Geometry*>(osg::clone(geometry.get(), osg::CopyOp::DEEP_COPY_NODES|osg::CopyOp::DEEP_COPY_DRAWABLES));
+                frameswitch->addChild(geometry);
+                frameswitch->addChild(geom2);
+#endif
+
                 parentNode->addChild(frameswitch);
             }
             else
+#if not(OSG_MIN_VERSION_REQUIRED(3,3,3))
                 parentNode->addChild(geode);
+#else
+                parentNode->addChild(geometry);
+#endif
         }
 
         osg::ref_ptr<osg::Geometry> handleMorphGeometry(const Nif::NiGeomMorpherController* morpher)
@@ -1056,8 +1075,6 @@ namespace NifOsg
         void handleSkinnedTriShape(const Nif::NiTriShape *triShape, osg::Group *parentNode, SceneUtil::CompositeStateSetUpdater* composite,
                                           const std::vector<int>& boundTextures, int animflags)
         {
-            osg::ref_ptr<osg::Geode> geode (new osg::Geode);
-
             osg::ref_ptr<osg::Geometry> geometry (new osg::Geometry);
             triShapeToGeometry(triShape, geometry, parentNode, composite, boundTextures, animflags);
 
@@ -1090,17 +1107,27 @@ namespace NifOsg
             }
             rig->setInfluenceMap(map);
 
-            geode->addDrawable(rig);
-
             // Add a copy, we will alternate between the two copies every other frame using the FrameSwitch
             // This is so we can set the DataVariance as STATIC, giving a huge performance boost
             rig->setDataVariance(osg::Object::STATIC);
+
+            osg::ref_ptr<FrameSwitch> frameswitch = new FrameSwitch;
+
+#if not(OSG_MIN_VERSION_REQUIRED(3,3,3))
+            osg::ref_ptr<osg::Geode> geode (new osg::Geode);
+            geode->addDrawable(rig);
+
             osg::Geode* geode2 = static_cast<osg::Geode*>(osg::clone(geode.get(), osg::CopyOp::DEEP_COPY_NODES|
                                                                      osg::CopyOp::DEEP_COPY_DRAWABLES));
 
-            osg::ref_ptr<FrameSwitch> frameswitch = new FrameSwitch;
             frameswitch->addChild(geode);
             frameswitch->addChild(geode2);
+#else
+            SceneUtil::RigGeometry* rig2 = static_cast<SceneUtil::RigGeometry*>(osg::clone(rig.get(), osg::CopyOp::DEEP_COPY_NODES|
+                                                                                           osg::CopyOp::DEEP_COPY_DRAWABLES));
+            frameswitch->addChild(rig);
+            frameswitch->addChild(rig2);
+#endif
 
             parentNode->addChild(frameswitch);
         }

components/resource/scenemanager.cpp

@@ -3,6 +3,7 @@
 #include <osg/Node>
 #include <osg/Geode>
 #include <osg/UserDataContainer>
+#include <osg/Version>
 
 #include <osgParticle/ParticleSystem>
 
@@ -32,30 +33,47 @@ namespace
         {
         }
 
-        void apply(osg::Node& node)
+        bool isWorldSpaceParticleSystem(osgParticle::ParticleSystem* partsys)
         {
-            if (osg::Geode* geode = node.asGeode())
+            // HACK: ParticleSystem has no getReferenceFrame()
+            return (partsys->getUserDataContainer()
+                    && partsys->getUserDataContainer()->getNumDescriptions() > 0
+                    && partsys->getUserDataContainer()->getDescriptions()[0] == "worldspace");
+        }
+
+        void apply(osg::Geode& geode)
+        {
+            for (unsigned int i=0;i<geode.getNumDrawables();++i)
             {
-                for (unsigned int i=0;i<geode->getNumDrawables();++i)
+                if (osgParticle::ParticleSystem* partsys = dynamic_cast<osgParticle::ParticleSystem*>(geode.getDrawable(i)))
                 {
-                    if (osgParticle::ParticleSystem* partsys = dynamic_cast<osgParticle::ParticleSystem*>(geode->getDrawable(i)))
+                    if (isWorldSpaceParticleSystem(partsys))
                     {
-                        // HACK: ParticleSystem has no getReferenceFrame()
-                        if (partsys->getUserDataContainer()
-                                && partsys->getUserDataContainer()->getNumDescriptions() > 0
-                                && partsys->getUserDataContainer()->getDescriptions()[0] == "worldspace")
-                        {
-                            // HACK: Ignore the InverseWorldMatrix transform the geode is attached to
-                            if (geode->getNumParents() && geode->getParent(0)->getNumParents())
-                                transformInitialParticles(partsys, geode->getParent(0)->getParent(0));
-                        }
-                        geode->setNodeMask(mMask);
+                        // HACK: Ignore the InverseWorldMatrix transform the geode is attached to
+                        if (geode.getNumParents() && geode.getParent(0)->getNumParents())
+                            transformInitialParticles(partsys, geode.getParent(0)->getParent(0));
                     }
+                    geode.setNodeMask(mMask);
                 }
             }
+        }
 
-            traverse(node);
+#if OSG_MIN_VERSION_REQUIRED(3,3,3)
+        // in OSG 3.3 and up Drawables can be directly in the scene graph without a Geode decorating them.
+        void apply(osg::Drawable& drw)
+        {
+            if (osgParticle::ParticleSystem* partsys = dynamic_cast<osgParticle::ParticleSystem*>(&drw))
+            {
+                if (isWorldSpaceParticleSystem(partsys))
+                {
+                    // HACK: Ignore the InverseWorldMatrix transform the particle system is attached to
+                    if (partsys->getNumParents() && partsys->getParent(0)->getNumParents())
+                        transformInitialParticles(partsys, partsys->getParent(0)->getParent(0));
+                }
+                partsys->setNodeMask(mMask);
+            }
         }
+#endif
 
         void transformInitialParticles(osgParticle::ParticleSystem* partsys, osg::Node* node)
         {

components/sceneutil/visitor.cpp

@@ -22,11 +22,13 @@ namespace SceneUtil
     void DisableFreezeOnCullVisitor::apply(osg::Geode &geode)
     {
         for (unsigned int i=0; i<geode.getNumDrawables(); ++i)
-        {
-            osg::Drawable* drw = geode.getDrawable(i);
-            if (osgParticle::ParticleSystem* partsys = dynamic_cast<osgParticle::ParticleSystem*>(drw))
-                partsys->setFreezeOnCull(false);
-        }
+            apply(*geode.getDrawable(i));
+    }
+
+    void DisableFreezeOnCullVisitor::apply(osg::Drawable& drw)
+    {
+        if (osgParticle::ParticleSystem* partsys = dynamic_cast<osgParticle::ParticleSystem*>(&drw))
+            partsys->setFreezeOnCull(false);
     }
 
 }

components/sceneutil/visitor.hpp

@@ -35,6 +35,7 @@ namespace SceneUtil
         }
 
         virtual void apply(osg::Geode &geode);
+        virtual void apply(osg::Drawable& drw);
     };
 
 }