OSG shadows

.gitignore

@@ -9,6 +9,7 @@ TAGS
 .DS_Store
 .cproject
 .project
+.vscode
 *.orig
 *.idb
 *.pdb

CHANGELOG.md

@@ -20,6 +20,7 @@
 * GUI
 
   * Added support of rendering texture images: [#973](https://github.com/dartsim/dart/pull/973)
+  * Added OSG shadows: [#978](https://github.com/dartsim/dart/pull/978)
 
 * License
 

dart/dynamics/ShapeFrame.cpp

@@ -39,9 +39,11 @@ namespace detail {
 
 //==============================================================================
 VisualAspectProperties::VisualAspectProperties(const Eigen::Vector4d& color,
-                                             const bool hidden)
+                                             const bool hidden,
+                                             const bool shadowed)
   : mRGBA(color),
-    mHidden(hidden)
+    mHidden(hidden),
+    mShadowed(shadowed)
 {
   // Do nothing
 }

dart/dynamics/ShapeFrame.hpp

@@ -67,12 +67,15 @@ class VisualAspect final :
   void setRGBA(const Eigen::Vector4d& color);
 
   DART_COMMON_GET_ASPECT_PROPERTY( Eigen::Vector4d, RGBA )
-  // void setRGBA(const Eigen::Vector4d& value);
   // const Eigen::Vector4d& getRGBA() const;
 
   DART_COMMON_SET_GET_ASPECT_PROPERTY( bool, Hidden )
-  // void setHidden(const Eigen::Vector4d& value);
-  // const Eigen::Vector4d& getHidden() const;
+  // void setHidden(const bool& value);
+  // const bool& getHidden() const;
+
+  DART_COMMON_SET_GET_ASPECT_PROPERTY( bool, Shadowed )
+  // void setShadowed(const bool& value);
+  // const bool& getShadowed() const;
 
   /// Identical to setRGB(const Eigen::Vector3d&)
   void setColor(const Eigen::Vector3d& color);

dart/dynamics/detail/ShapeFrameAspect.hpp

@@ -58,10 +58,14 @@ struct VisualAspectProperties
   /// True if this shape node should be kept from rendering
   bool mHidden;
 
+  /// True if this shape node should be shadowed
+  bool mShadowed;
+
   /// Constructor
   VisualAspectProperties(
       const Eigen::Vector4d& color = Eigen::Vector4d(0.5, 0.5, 1.0, 1.0),
-      const bool hidden = false);
+      const bool hidden = false,
+      const bool shadowed = true);
 
   /// Destructor
   virtual ~VisualAspectProperties() = default;

dart/gui/osg/CMakeLists.txt

@@ -7,7 +7,7 @@ endif()
 if(DART_BUILD_GUI_OSG)
 
   find_package(OpenSceneGraph 3.0 QUIET
-    COMPONENTS osg osgViewer osgManipulator osgGA osgDB)
+    COMPONENTS osg osgViewer osgManipulator osgGA osgDB osgShadow)
 
   # It seems that OPENSCENEGRAPH_FOUND will inadvertently get set to true when
   # OpenThreads is found, even if OpenSceneGraph is not installed. This is quite

dart/gui/osg/InteractiveFrame.cpp

@@ -116,6 +116,8 @@ dart::dynamics::SimpleFrame* InteractiveTool::addShapeFrame(
   auto shapeFrame = mSimpleFrames.back().get();
   shapeFrame->setShape(shape);
   shapeFrame->createVisualAspect();
+  // Disable shadowing for InteractiveTool
+  shapeFrame->getVisualAspect(true)->setShadowed(false);
 
   return shapeFrame;
 }
@@ -230,6 +232,8 @@ dart::dynamics::SimpleFrame* InteractiveFrame::addShapeFrame(
   auto shapeFrame = mSimpleFrames.back().get();
   shapeFrame->setShape(shape);
   shapeFrame->createVisualAspect();
+  // Disable shadowing for InteractiveFrame
+  shapeFrame->getVisualAspect(true)->setShadowed(false);
 
   return shapeFrame;
 }

dart/gui/osg/Viewer.cpp

@@ -380,6 +380,9 @@ void Viewer::addWorldNode(WorldNode* _newWorldNode, bool _active)
     _newWorldNode->simulate(mSimulating);
   _newWorldNode->mViewer = this;
   _newWorldNode->setupViewer();
+  // set again the shadow technique to produce warning for ImGuiViewer
+  if(_newWorldNode->isShadowed())
+    _newWorldNode->setShadowTechnique(_newWorldNode->getShadowTechnique());
 }
 
 //==============================================================================
@@ -468,6 +471,15 @@ const ::osg::Group* Viewer::getLightGroup() const
   return mLightGroup;
 }
 
+//==============================================================================
+const ::osg::ref_ptr<::osg::LightSource>& Viewer::getLightSource(std::size_t index) const
+{
+  assert(index < 2);
+  if(index == 0)
+    return mLightSource1;
+  return mLightSource2;
+}
+
 //==============================================================================
 void Viewer::setupDefaultLights()
 {

dart/gui/osg/Viewer.hpp

@@ -38,6 +38,7 @@
 #include <memory>
 
 #include <osgViewer/Viewer>
+#include <osgShadow/ShadowTechnique>
 
 #include <Eigen/Core>
 
@@ -114,7 +115,6 @@ class ViewerAttachment : public virtual ::osg::Group
 class Viewer : public osgViewer::Viewer, public dart::common::Subject
 {
 public:
-
   /// Constructor for dart::gui::osg::Viewer. This will automatically create the
   /// default event handler.
   Viewer(const ::osg::Vec4& clearColor = ::osg::Vec4(0.9,0.9,0.9,1.0));
@@ -197,6 +197,11 @@ class Viewer : public osgViewer::Viewer, public dart::common::Subject
   /// Get the Group node that contains the LightSources for this Viewer
   const ::osg::Group* getLightGroup() const;
 
+  /// Get one of the LightSources of this Viewer
+  /// index either 0 or 1
+  /// Useful for shadowing techniques
+  const ::osg::ref_ptr<::osg::LightSource>& getLightSource(std::size_t index = 0) const;
+
   /// Set up the default lighting scheme
   void setupDefaultLights();
 

dart/gui/osg/WorldNode.cpp

@@ -34,8 +34,12 @@
 
 #include <osg/NodeCallback>
 
+#include <osgShadow/ShadowedScene>
+#include <osgShadow/ShadowMap>
+
 #include "dart/gui/osg/WorldNode.hpp"
 #include "dart/gui/osg/ShapeFrameNode.hpp"
+#include "dart/gui/osg/ImGuiViewer.hpp"
 
 #include "dart/simulation/World.hpp"
 #include "dart/dynamics/Skeleton.hpp"
@@ -61,19 +65,40 @@ class WorldNodeCallback : public ::osg::NodeCallback
 };
 
 //==============================================================================
-WorldNode::WorldNode(std::shared_ptr<dart::simulation::World> _world)
-  : mWorld(_world),
+WorldNode::WorldNode(std::shared_ptr<dart::simulation::World> world, ::osg::ref_ptr<osgShadow::ShadowTechnique> shadowTechnique)
+  : mWorld(world),
     mSimulating(false),
     mNumStepsPerCycle(1),
-    mViewer(nullptr)
+    mViewer(nullptr),
+    mNormalGroup(new ::osg::Group)
 {
+  // Flags for shadowing; maybe this needs to be global?
+  constexpr int ReceivesShadowTraversalMask = 0x2;
+  constexpr int CastsShadowTraversalMask = 0x1;
+
+  // Setup shadows
+  // Create a ShadowedScene
+  ::osg::ref_ptr<osgShadow::ShadowedScene> shadowedScene = new osgShadow::ShadowedScene;
+  shadowedScene->setReceivesShadowTraversalMask(ReceivesShadowTraversalMask);
+  shadowedScene->setCastsShadowTraversalMask(CastsShadowTraversalMask);
+
+  // set the shadowed group
+  mShadowedGroup = shadowedScene.get();
+  mShadowedGroup->getOrCreateStateSet();
+
+  // Add normal and shadowed groups
+  addChild(mNormalGroup);
+  addChild(mShadowedGroup);
+
+  setShadowTechnique(shadowTechnique);
+
   setUpdateCallback(new WorldNodeCallback);
 }
 
 //==============================================================================
-void WorldNode::setWorld(std::shared_ptr<dart::simulation::World> _newWorld)
+void WorldNode::setWorld(std::shared_ptr<dart::simulation::World> newWorld)
 {
-  mWorld = _newWorld;
+  mWorld = newWorld;
 }
 
 //==============================================================================
@@ -138,15 +163,15 @@ bool WorldNode::isSimulating() const
 }
 
 //==============================================================================
-void WorldNode::simulate(bool _on)
+void WorldNode::simulate(bool on)
 {
-  mSimulating = _on;
+  mSimulating = on;
 }
 
 //==============================================================================
-void WorldNode::setNumStepsPerCycle(std::size_t _steps)
+void WorldNode::setNumStepsPerCycle(std::size_t steps)
 {
-  mNumStepsPerCycle = _steps;
+  mNumStepsPerCycle = steps;
 }
 
 //==============================================================================
@@ -193,7 +218,11 @@ void WorldNode::clearUnusedNodes()
   {
     NodeMap::iterator it = mFrameToNode.find(frame);
     ShapeFrameNode* node = it->second;
-    removeChild(node);
+    if(!node->getShapeFrame() || !node->getShapeFrame()->hasVisualAspect() || !node->getShapeFrame()->getVisualAspect(true)->getShadowed()) {
+      mNormalGroup->removeChild(node);
+    }
+    else
+      mShadowedGroup->removeChild(node);
     mFrameToNode.erase(it);
   }
 }
@@ -260,6 +289,16 @@ void WorldNode::refreshShapeFrameNode(dart::dynamics::Frame* frame)
     if(!node)
       return;
 
+    // update the group that ShapeFrameNode should be
+    if((!node->getShapeFrame()->hasVisualAspect() || !node->getShapeFrame()->getVisualAspect(true)->getShadowed()) && node->getParent(0) != mNormalGroup) {
+      mShadowedGroup->removeChild(node);
+      mNormalGroup->addChild(node);
+    }
+    else if(node->getShapeFrame()->hasVisualAspect() && node->getShapeFrame()->getVisualAspect(true)->getShadowed() && node->getParent(0) != mShadowedGroup) {
+      mNormalGroup->removeChild(node);
+      mShadowedGroup->addChild(node);
+    }
+
     node->refresh(true);
     return;
   }
@@ -276,7 +315,52 @@ void WorldNode::refreshShapeFrameNode(dart::dynamics::Frame* frame)
   ::osg::ref_ptr<ShapeFrameNode> node = new ShapeFrameNode(frame->asShapeFrame(),
                                                          this);
   it->second = node;
-  addChild(node);
+  if(!node->getShapeFrame()->hasVisualAspect() || !node->getShapeFrame()->getVisualAspect(true)->getShadowed()) {
+    mNormalGroup->addChild(node);
+  }
+  else
+    mShadowedGroup->addChild(node);
+}
+
+//==============================================================================
+bool WorldNode::isShadowed() const
+{
+  return mShadowed;
+}
+
+//==============================================================================
+void WorldNode::setShadowTechnique(::osg::ref_ptr<osgShadow::ShadowTechnique> shadowTechnique) {
+  if(!shadowTechnique) {
+    mShadowed = false;
+    static_cast<osgShadow::ShadowedScene*>(mShadowedGroup.get())->setShadowTechnique(nullptr);
+  }
+  else {
+    ImGuiViewer* viewer = mViewer ? dynamic_cast<ImGuiViewer*>(mViewer) : nullptr;
+    if(viewer)
+      dtwarn << "[WorldNode] You are enabling shadows inside an ImGuiViewer. "
+             << "The ImGui windows may not render properly.\n";
+    mShadowed = true;
+    static_cast<osgShadow::ShadowedScene*>(mShadowedGroup.get())->setShadowTechnique(shadowTechnique.get());
+  }
+}
+
+//==============================================================================
+::osg::ref_ptr<osgShadow::ShadowTechnique> WorldNode::getShadowTechnique() const {
+  if(!mShadowed)
+    return nullptr;
+  return static_cast<osgShadow::ShadowedScene*>(mShadowedGroup.get())->getShadowTechnique();
+}
+
+//==============================================================================
+::osg::ref_ptr<osgShadow::ShadowTechnique> WorldNode::createDefaultShadowTechnique(const Viewer* viewer) {
+  ::osg::ref_ptr<osgShadow::ShadowMap> sm = new osgShadow::ShadowMap;
+  // increase the resolution of default shadow texture for higher quality
+  int mapres = std::pow(2, 13);
+  sm->setTextureSize(::osg::Vec2s(mapres,mapres));
+  // we are using Light1 because this is the highest one (on up direction)
+  sm->setLight(viewer->getLightSource(0));
+
+  return sm;
 }
 
 } // namespace osg

dart/gui/osg/WorldNode.hpp

@@ -34,6 +34,7 @@
 #define DART_GUI_OSG_WORLDNODE_HPP_
 
 #include <osg/Group>
+#include <osgShadow/ShadowTechnique>
 #include <unordered_map>
 #include <memory>
 
@@ -67,10 +68,11 @@ class WorldNode : public ::osg::Group
   friend class Viewer;
 
   /// Default constructor
-  explicit WorldNode(std::shared_ptr<dart::simulation::World> _world = nullptr);
+  /// Shadows are disabled by default
+  explicit WorldNode(std::shared_ptr<dart::simulation::World> world = nullptr, ::osg::ref_ptr<osgShadow::ShadowTechnique> shadowTechnique = nullptr);
 
   /// Set the World that this WorldNode is associated with
-  void setWorld(std::shared_ptr<dart::simulation::World> _newWorld);
+  void setWorld(std::shared_ptr<dart::simulation::World> newWorld);
 
   /// Get the World that this WorldNode is associated with
   std::shared_ptr<dart::simulation::World> getWorld() const;
@@ -119,16 +121,31 @@ class WorldNode : public ::osg::Group
 
   /// Pass in true to take steps between render cycles; pass in false to turn
   /// off steps between render cycles.
-  void simulate(bool _on);
+  void simulate(bool on);
 
   /// Set the number of steps to take between each render cycle (only if the
   /// simulation is not paused)
-  void setNumStepsPerCycle(std::size_t _steps);
+  void setNumStepsPerCycle(std::size_t steps);
 
   /// Get the number of steps that will be taken between each render cycle (only
   /// if the simulation is not paused)
   std::size_t getNumStepsPerCycle() const;
 
+  /// Get whether the WorldNode is casting shadows
+  bool isShadowed() const;
+
+  /// Set the ShadowTechnique
+  /// If you wish to disable shadows, pass a nullptr
+  void setShadowTechnique(::osg::ref_ptr<osgShadow::ShadowTechnique> shadowTechnique = nullptr);
+
+  /// Get the current ShadowTechnique
+  /// nullptr is there are no shadows
+  ::osg::ref_ptr<osgShadow::ShadowTechnique> getShadowTechnique() const;
+
+  /// Helper function to create a default ShadowTechnique given a Viewer
+  /// the default ShadowTechnique is ShadowMap
+  static ::osg::ref_ptr<osgShadow::ShadowTechnique> createDefaultShadowTechnique(const Viewer* viewer);
+
 protected:
 
   /// Destructor
@@ -173,6 +190,15 @@ class WorldNode : public ::osg::Group
   /// Viewer that this WorldNode is inside of
   Viewer* mViewer;
 
+  /// OSG group for non-shadowed objects
+  ::osg::ref_ptr<::osg::Group> mNormalGroup;
+
+  /// OSG group for shadowed objects
+  ::osg::ref_ptr<::osg::Group> mShadowedGroup;
+
+  /// Whether the shadows are enabled
+  bool mShadowed;
+
 };
 
 } // namespace osg