From Paul Martz, Introduced osg::OcclusionQueryNode with support for OpenGL occlusion query extension

This commit is contained in:
Robert Osfield 2007-12-21 14:45:16 +00:00
parent 5f7a2968ac
commit 4889342c4a
10 changed files with 1693 additions and 0 deletions

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@ -52,6 +52,7 @@ IF(DYNAMIC_OPENSCENEGRAPH)
ADD_SUBDIRECTORY(osgmovie)
ADD_SUBDIRECTORY(osgmultitexture)
ADD_SUBDIRECTORY(osgoccluder)
ADD_SUBDIRECTORY(osgocclusionquery)
ADD_SUBDIRECTORY(osgpagedlod)
ADD_SUBDIRECTORY(osgparametric)
ADD_SUBDIRECTORY(osgparticle)

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@ -0,0 +1,7 @@
#this file is automatically generated
SET(TARGET_SRC osgocclusionquery.cpp )
SET(TARGET_ADDED_LIBRARIES osgUtil osgDB )
#### end var setup ###
SETUP_EXAMPLE(osgocclusionquery)

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@ -0,0 +1,850 @@
/* OpenSceneGraph example, osganimate.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
// This exampl demonstrates use of OcclusionQueryNode.
//
// In general, you use OcclusionQueryNode by simply attaching a subgraph
// or subgraphs as children, and it performs an OpenGL oclusion query
// to determine whether to draw the subgraphs or not.
//
// You can manually insert OcclusionQueryNodes at strategic locations
// in your scene graph, or you can write a NodeVisitor to insert them
// automatically, as this example shows.
//
// Run this example with no command line arguments, and it creates
// a "stock scene" to show how OcclusionQueryNode can be used.
//
// Or, run this example with a model on the command line, and the
// example uses a NodeVisitor to try to find worthwhile locations
// for OcclusionQueryNodes in your the scene graph.
#include <osg/NodeVisitor>
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/StateSet>
#include <osg/StateAttribute>
#include <osg/PolygonMode>
#include <osg/ColorMask>
#include <osg/PolygonOffset>
#include <osg/Depth>
#include <osgDB/ReadFile>
#include <osgDB/WriteFile>
#include <osgUtil/Optimizer>
#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>
#include <osgGA/StateSetManipulator>
#include <osg/OcclusionQueryNode>
#include <iostream>
#include <sstream>
// NodeVisitors and utility functions for OcclusionQueryNode
// Create and return a StateSet appropriate for performing an occlusion
// query test (disable lighting, texture mapping, etc). Probably some
// room for improvement here. Could disable shaders, for example.
osg::StateSet*
initOQState()
{
osg::StateSet* state = new osg::StateSet;
// TBD Possible bug, need to allow user to set render bin number.
state->setRenderBinDetails( 9, "RenderBin" );
state->setMode( GL_LIGHTING, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
state->setTextureMode( 0, GL_TEXTURE_2D, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
state->setMode( GL_CULL_FACE, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::ColorMask* cm = new osg::ColorMask( false, false, false, false );
state->setAttributeAndModes( cm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::Depth* d = new osg::Depth( osg::Depth::LEQUAL, 0.f, 1.f, false );
state->setAttributeAndModes( d, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonMode* pm = new osg::PolygonMode(
osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::FILL );
state->setAttributeAndModes( pm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonOffset* po = new osg::PolygonOffset( -1., -1. );
state->setAttributeAndModes( po, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
return state;
}
// Create and return a StateSet for rendering a debug representation of query geometry.
osg::StateSet*
initOQDebugState()
{
osg::StateSet* debugState = new osg::StateSet;
debugState->setMode( GL_LIGHTING, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
debugState->setTextureMode( 0, GL_TEXTURE_2D, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
debugState->setMode( GL_CULL_FACE, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonMode* pm = new osg::PolygonMode(
osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::LINE );
debugState->setAttributeAndModes( pm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonOffset* po = new osg::PolygonOffset( -1., -1. );
debugState->setAttributeAndModes( po, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
return debugState;
}
// Use this visitor to insert OcclusionQueryNodes (OQNs) in the
// visited subgraph. Only one OQN will test any particular node
// (no nesting). See also OcclusionQueryNonFlatVisitor.
class OcclusionQueryVisitor : public osg::NodeVisitor
{
public:
OcclusionQueryVisitor();
virtual ~OcclusionQueryVisitor();
// Specify the vertex count threshold for performing occlusion
// query tests. Nodes in the scene graph whose total child geometry
// contains fewer vertices than the specified threshold will
// never be tested, just drawn. (In fact, they will br treated as
// potential occluders and rendered first in front-to-back order.)
void setOccluderThreshold( int vertices );
int getOccluderThreshold() const;
virtual void apply( osg::OcclusionQueryNode& oqn );
virtual void apply( osg::Group& group );
virtual void apply( osg::Geode& geode );
protected:
void addOQN( osg::Node& node );
// When an OQR creates all OQNs and each OQN shares the same OQC,
// these methods are used to uniquely name all OQNs. Handy
// for debugging.
std::string getNextOQNName();
int getNameIdx() const { return _nameIdx; }
osg::ref_ptr<osg::StateSet> _state;
osg::ref_ptr<osg::StateSet> _debugState;
unsigned int _nameIdx;
int _occluderThreshold;
};
// Find all OQNs in the visited scene graph and set their visibility threshold.
class VisibilityThresholdVisitor : public osg::NodeVisitor
{
public:
VisibilityThresholdVisitor( unsigned int threshold=500 )
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN ),
_visThreshold( threshold ) {}
virtual ~VisibilityThresholdVisitor() {}
virtual void apply( osg::OcclusionQueryNode& oqn );
protected:
unsigned int _visThreshold;
};
// Find all OQNs in the visited scene graph and set the number of frames
// between queries.
class QueryFrameCountVisitor : public osg::NodeVisitor
{
public:
QueryFrameCountVisitor( int count=5 )
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN ),
_count( count ) {}
virtual ~QueryFrameCountVisitor() {}
virtual void apply( osg::OcclusionQueryNode& oqn );
protected:
unsigned int _count;
};
// Find all OQNs in the visited scene graph and enable or disable queries..
class EnableQueryVisitor : public osg::NodeVisitor
{
public:
EnableQueryVisitor( bool enable=true )
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN ),
_enabled( enable ) {}
virtual ~EnableQueryVisitor() {}
virtual void apply( osg::OcclusionQueryNode& oqn );
protected:
bool _enabled;
};
// Find all OQNs in the visited scene graph and enable or disable the
// debug bounding volume display.
class DebugDisplayVisitor : public osg::NodeVisitor
{
public:
DebugDisplayVisitor( bool debug=true )
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN ),
_debug( debug ) {}
virtual ~DebugDisplayVisitor() {}
virtual void apply( osg::OcclusionQueryNode& oqn );
protected:
bool _debug;
};
// Remove all OQNs from the visited scene graph.
class RemoveOcclusionQueryVisitor : public osg::NodeVisitor
{
public:
RemoveOcclusionQueryVisitor();
virtual ~RemoveOcclusionQueryVisitor();
virtual void apply( osg::OcclusionQueryNode& oqn );
protected:
};
// Gather statistics about OQN performance in the visited scene graph.
class StatisticsVisitor : public osg::NodeVisitor
{
public:
StatisticsVisitor( osg::NodeVisitor::TraversalMode mode=osg::NodeVisitor::TRAVERSE_ACTIVE_CHILDREN );
virtual ~StatisticsVisitor();
virtual void apply( osg::OcclusionQueryNode& oqn );
void reset();
unsigned int getNumOQNs() const;
unsigned int getNumPassed() const;
protected:
unsigned int _numOQNs;
unsigned int _numPassed;
};
unsigned int countGeometryVertices( osg::Geometry* geom )
{
if (!geom->getVertexArray())
return 0;
// TBD This will eventually iterate over the PrimitiveSets and total the
// number of vertices actually used. But for now, it just returns the
// size of the vertex array.
return geom->getVertexArray()->getNumElements();
}
class VertexCounter : public osg::NodeVisitor
{
public:
VertexCounter( int limit )
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN ),
_limit( limit ),
_total( 0 ) {}
~VertexCounter() {}
int getTotal() { return _total; }
bool exceeded() const { return _total > _limit; }
void reset() { _total = 0; }
virtual void apply( osg::Node& node )
{
// Check for early abort. If out total already exceeds the
// max number of vertices, no need to traverse further.
if (exceeded())
return;
traverse( node );
}
virtual void apply( osg::Geode& geode )
{
// Possible early abort.
if (exceeded())
return;
unsigned int i;
for( i = 0; i < geode.getNumDrawables(); i++ )
{
osg::Geometry* geom = dynamic_cast<osg::Geometry *>(geode.getDrawable(i));
if( !geom )
continue;
_total += countGeometryVertices( geom );
if (_total > _limit)
break;
}
}
protected:
int _limit;
int _total;
};
OcclusionQueryVisitor::OcclusionQueryVisitor()
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN ),
_nameIdx( 0 ),
_occluderThreshold( 5000 )
{
// Init StateSet for occlusion query geometry.
_state = initOQState();
// Initialize StateSet for debug geometry
_debugState = initOQDebugState();
}
OcclusionQueryVisitor::~OcclusionQueryVisitor()
{
osg::notify( osg::INFO ) <<
"osgOQ: OcclusionQueryVisitor: Added " << getNameIdx() <<
" OQNodes." << std::endl;
}
void
OcclusionQueryVisitor::setOccluderThreshold( int vertices )
{
_occluderThreshold = vertices;
}
int
OcclusionQueryVisitor::getOccluderThreshold() const
{
return _occluderThreshold;
}
void
OcclusionQueryVisitor::apply( osg::OcclusionQueryNode& oqn )
{
// A subgraph is already under osgOQ control.
// Don't traverse further.
return;
}
void
OcclusionQueryVisitor::apply( osg::Group& group )
{
if (group.getNumParents() == 0)
{
// Can't add an OQN above a root node.
traverse( group );
return;
}
int preTraverseOQNCount = getNameIdx();
traverse( group );
if (getNameIdx() > preTraverseOQNCount)
// A least one OQN was added below the current node.
// Don't add one here to avoid hierarchical nesting.
return;
// There are no OQNs below this group. If the vertex
// count exceeds the threshold, add an OQN here.
addOQN( group );
}
void
OcclusionQueryVisitor::apply( osg::Geode& geode )
{
if (geode.getNumParents() == 0)
{
// Can't add an OQN above a root node.
traverse( geode );
return;
}
addOQN( geode );
}
void
OcclusionQueryVisitor::addOQN( osg::Node& node )
{
VertexCounter vc( _occluderThreshold );
node.accept( vc );
if (vc.exceeded())
{
// Insert OQN(s) above this node.
unsigned int np = node.getNumParents();
while (np--)
{
osg::Group* parent = dynamic_cast<osg::Group*>( node.getParent( np ) );
if (parent != NULL)
{
osg::ref_ptr<osg::OcclusionQueryNode> oqn = new osg::OcclusionQueryNode();
oqn->addChild( &node );
parent->replaceChild( &node, oqn.get() );
oqn->setName( getNextOQNName() );
// Set all OQNs to use the same query StateSets (instead of multiple copies
// of the same StateSet) for efficiency.
oqn->setQueryStateSets( _state.get(), _debugState.get() );
}
}
}
}
std::string
OcclusionQueryVisitor::getNextOQNName()
{
std::ostringstream ostr;
ostr << "OQNode_" << _nameIdx++;
return ostr.str();
}
//
void
VisibilityThresholdVisitor::apply( osg::OcclusionQueryNode& oqn )
{
oqn.setVisibilityThreshold( _visThreshold );
traverse( oqn );
}
void
QueryFrameCountVisitor::apply( osg::OcclusionQueryNode& oqn )
{
oqn.setQueryFrameCount( _count );
traverse( oqn );
}
void
EnableQueryVisitor::apply( osg::OcclusionQueryNode& oqn )
{
oqn.setQueriesEnabled( _enabled );
traverse( oqn );
}
void
DebugDisplayVisitor::apply( osg::OcclusionQueryNode& oqn )
{
oqn.setDebugDisplay( _debug );
traverse( oqn );
}
RemoveOcclusionQueryVisitor::RemoveOcclusionQueryVisitor()
: osg::NodeVisitor( osg::NodeVisitor::TRAVERSE_ALL_CHILDREN )
{
}
RemoveOcclusionQueryVisitor::~RemoveOcclusionQueryVisitor()
{
}
void
RemoveOcclusionQueryVisitor::apply( osg::OcclusionQueryNode& oqn )
{
if (oqn.getNumParents() == 0)
{
// Even if this is an OQN, can't delete it because it's the root.
traverse( oqn );
return;
}
osg::ref_ptr<osg::OcclusionQueryNode> oqnPtr = &oqn;
unsigned int np = oqn.getNumParents();
while (np--)
{
osg::Group* parent = dynamic_cast<osg::Group*>( oqn.getParent( np ) );
if (parent != NULL)
{
// Remove OQN from parent.
parent->removeChild( oqnPtr.get() );
// Add OQN's children to parent.
unsigned int nc = oqn.getNumChildren();
while (nc--)
parent->addChild( oqn.getChild( nc ) );
}
}
}
StatisticsVisitor::StatisticsVisitor( osg::NodeVisitor::TraversalMode mode )
: osg::NodeVisitor( mode ),
_numOQNs( 0 ),
_numPassed( 0 )
{
}
StatisticsVisitor::~StatisticsVisitor()
{
}
void
StatisticsVisitor::apply( osg::OcclusionQueryNode& oqn )
{
_numOQNs++;
if (oqn.getPassed())
_numPassed++;
traverse( oqn );
}
void
StatisticsVisitor::reset()
{
_numOQNs = _numPassed = 0;
}
unsigned int
StatisticsVisitor::getNumOQNs() const
{
return _numOQNs;
}
unsigned int
StatisticsVisitor::getNumPassed() const
{
return _numPassed;
}
// End NodeVisitors
// KetHandler --
// Allow user to do interesting things with an
// OcclusionQueryNode-enabled scene graph at run time.
class KeyHandler : public osgGA::GUIEventHandler
{
public:
KeyHandler( osg::Node& node )
: _node( node ),
_enable( true ),
_debug( false )
{}
bool handle( const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& )
{
switch( ea.getEventType() )
{
case(osgGA::GUIEventAdapter::KEYUP):
{
if (ea.getKey()==osgGA::GUIEventAdapter::KEY_F6)
{
// F6 -- Toggle osgOQ testing.
_enable = !_enable;
EnableQueryVisitor eqv( _enable );
_node.accept( eqv );
return true;
}
else if (ea.getKey()==osgGA::GUIEventAdapter::KEY_F7)
{
// F7 -- Toggle display of OQ test bounding volumes
_debug = !_debug;
DebugDisplayVisitor ddv( _debug );
_node.accept( ddv );
return true;
}
else if (ea.getKey()==osgGA::GUIEventAdapter::KEY_F8)
{
// F8 -- Gether stats and display
StatisticsVisitor sv;
_node.accept( sv );
std::cout << "osgOQ: Stats: numOQNs " << sv.getNumOQNs() << ", numPased " << sv.getNumPassed() << std::endl;
return true;
}
else if (ea.getKey()==osgGA::GUIEventAdapter::KEY_F9)
{
// F9 -- Remove all OcclusionQueryNodes
RemoveOcclusionQueryVisitor roqv;
_node.accept( roqv );
return true;
}
else if (ea.getKey()=='o')
{
if (osgDB::writeNodeFile( _node, "saved_model.osg" ))
osg::notify( osg::ALWAYS ) << "osgOQ: Wrote scene graph to \"saved_model.osg\"" << std::endl;
else
osg::notify( osg::ALWAYS ) << "osgOQ: Wrote failed for \"saved_model.osg\"" << std::endl;
return true;
}
return false;
}
default:
break;
}
return false;
}
osg::Node& _node;
bool _enable, _debug;
};
// Create a cube with one side missing. This makes a great simple occluder.
osg::ref_ptr<osg::Node>
createBox()
{
osg::ref_ptr<osg::Geode> box = new osg::Geode;
osg::StateSet* state = box->getOrCreateStateSet();
osg::PolygonMode* pm = new osg::PolygonMode(
osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::FILL );
state->setAttributeAndModes( pm,
osg::StateAttribute::ON | osg::StateAttribute::PROTECTED );
osg::ref_ptr<osg::Geometry> geom = new osg::Geometry;
osg::ref_ptr<osg::Vec3Array> v = new osg::Vec3Array;
geom->setVertexArray( v.get() );
{
const float x( 0.f );
const float y( 0.f );
const float z( 0.f );
const float r( 1.1f );
v->push_back( osg::Vec3( x-r, y-r, z-r ) ); //left -X
v->push_back( osg::Vec3( x-r, y-r, z+r ) );
v->push_back( osg::Vec3( x-r, y+r, z+r ) );
v->push_back( osg::Vec3( x-r, y+r, z-r ) );
v->push_back( osg::Vec3( x+r, y-r, z+r ) ); //right +X
v->push_back( osg::Vec3( x+r, y-r, z-r ) );
v->push_back( osg::Vec3( x+r, y+r, z-r ) );
v->push_back( osg::Vec3( x+r, y+r, z+r ) );
v->push_back( osg::Vec3( x-r, y-r, z-r ) ); // bottom -Z
v->push_back( osg::Vec3( x-r, y+r, z-r ) );
v->push_back( osg::Vec3( x+r, y+r, z-r ) );
v->push_back( osg::Vec3( x+r, y-r, z-r ) );
v->push_back( osg::Vec3( x-r, y-r, z+r ) ); // top +Z
v->push_back( osg::Vec3( x+r, y-r, z+r ) );
v->push_back( osg::Vec3( x+r, y+r, z+r ) );
v->push_back( osg::Vec3( x-r, y+r, z+r ) );
v->push_back( osg::Vec3( x-r, y+r, z-r ) ); // back +Y
v->push_back( osg::Vec3( x-r, y+r, z+r ) );
v->push_back( osg::Vec3( x+r, y+r, z+r ) );
v->push_back( osg::Vec3( x+r, y+r, z-r ) );
}
osg::ref_ptr<osg::Vec4Array> c = new osg::Vec4Array;
geom->setColorArray( c.get() );
geom->setColorBinding( osg::Geometry::BIND_OVERALL );
c->push_back( osg::Vec4( 0.f, 1.f, 1.f, 1.f ) );
osg::ref_ptr<osg::Vec3Array> n = new osg::Vec3Array;
geom->setNormalArray( n.get() );
geom->setNormalBinding( osg::Geometry::BIND_PER_PRIMITIVE );
n->push_back( osg::Vec3( -1.f, 0.f, 0.f ) );
n->push_back( osg::Vec3( 1.f, 0.f, 0.f ) );
n->push_back( osg::Vec3( 0.f, 0.f, -1.f ) );
n->push_back( osg::Vec3( 0.f, 0.f, 1.f ) );
n->push_back( osg::Vec3( 0.f, 1.f, 0.f ) );
geom->addPrimitiveSet( new osg::DrawArrays( GL_QUADS, 0, 20 ) );
box->addDrawable( geom.get() );
return box.get();
}
// Make a Geometry that renders slow intentionally.
// To make sure it renders slow, we do the following:
// * Disable display lists
// * Force glBegin/glEnd slow path
// * Lots of vertices and color data per vertex
// * No vertex sharing
osg::ref_ptr<osg::Node>
createRandomTriangles( unsigned int num )
{
osg::ref_ptr<osg::Geode> tris = new osg::Geode;
osg::StateSet* state = tris->getOrCreateStateSet();
osg::StateSet* ss = tris->getOrCreateStateSet();
// Force wireframe. Many gfx cards handle this poorly.
osg::PolygonMode* pm = new osg::PolygonMode(
osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::LINE );
ss->setAttributeAndModes( pm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
ss->setMode( GL_LIGHTING, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
osg::ref_ptr<osg::Geometry> geom = new osg::Geometry;
// Disable display lists to decrease performance.
geom->setUseDisplayList( false );
osg::ref_ptr<osg::Vec3Array> v = new osg::Vec3Array;
geom->setVertexArray( v.get() );
v->resize( num*3 );
unsigned int i;
srand( 0 );
#define RAND_NEG1_TO_1 ( ((rand()%20)-10)*.1 )
for (i=0; i<num; i++)
{
osg::Vec3& v0 = (*v)[ i*3+0 ];
osg::Vec3& v1 = (*v)[ i*3+1 ];
osg::Vec3& v2 = (*v)[ i*3+2 ];
v0 = osg::Vec3( RAND_NEG1_TO_1, RAND_NEG1_TO_1, RAND_NEG1_TO_1 );
v1 = osg::Vec3( RAND_NEG1_TO_1, RAND_NEG1_TO_1, RAND_NEG1_TO_1 );
v2 = osg::Vec3( RAND_NEG1_TO_1, RAND_NEG1_TO_1, RAND_NEG1_TO_1 );
}
osg::ref_ptr<osg::Vec4Array> c = new osg::Vec4Array;
geom->setColorArray( c.get() );
// Bind per primitive to force slow glBegin/glEnd path.
geom->setColorBinding( osg::Geometry::BIND_PER_PRIMITIVE );
c->resize( num );
#define RAND_0_TO_1 ( (rand()%10)*.1 )
for (i=0; i<num; i++)
{
osg::Vec4& c0 = (*c)[ i ];
c0 = osg::Vec4( RAND_0_TO_1, RAND_0_TO_1, RAND_0_TO_1, 1. );
}
geom->addPrimitiveSet( new osg::DrawArrays( GL_TRIANGLES, 0, num*3 ) );
tris->addDrawable( geom.get() );
return tris.get();
}
// Create the stock scene:
// Top level Group
// Geode (simple occluder
// OcclusionQueryNode
// Geode with complex, slow geometry.
osg::ref_ptr<osg::Node>
createStockScene()
{
// Create a simple box occluder
osg::ref_ptr<osg::Group> root = new osg::Group();
root->addChild( createBox().get() );
// Create a complex mess of triangles as a child below an
// OcclusionQueryNode. The OQN will ensure that the
// subgraph isn't rendered when it's not visible.
osg::ref_ptr<osg::OcclusionQueryNode> oqn = new osg::OcclusionQueryNode;
oqn->addChild( createRandomTriangles( 20000 ).get() );
root->addChild( oqn.get() );
return root.get();
}
int main(int argc, char** argv)
{
// use an ArgumentParser object to manage the program arguments.
osg::ArgumentParser arguments(&argc,argv);
arguments.getApplicationUsage()->setApplicationName(arguments.getApplicationName());
arguments.getApplicationUsage()->setDescription(arguments.getApplicationName()+" demonstrates OpenGL occlusion query in OSG using the OcclusionQueryNode.");
arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] [filename(s)]");
arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display command line parameters");
// if user request help write it out to cout.
if (arguments.read("-h") || arguments.read("--help"))
{
arguments.getApplicationUsage()->write(std::cout, osg::ApplicationUsage::COMMAND_LINE_OPTION);
return 1;
}
// report any errors if they have occurred when parsing the program arguments.
if (arguments.errors())
{
arguments.writeErrorMessages(std::cout);
return 1;
}
osgViewer::Viewer viewer( arguments );
// add the state manipulator
viewer.addEventHandler( new osgGA::StateSetManipulator(viewer.getCamera()->getOrCreateStateSet()) );
// add the stats handler
viewer.addEventHandler(new osgViewer::StatsHandler);
// add the help handler
viewer.addEventHandler(new osgViewer::HelpHandler(arguments.getApplicationUsage()));
// load the specified model
osg::ref_ptr<osg::Node> root = osgDB::readNodeFiles( arguments );
if (!root)
{
std::cout << arguments.getApplicationName() <<": No files specified, or can't load them." << std::endl;
root = createStockScene().get();
if (!root)
{
std::cout << arguments.getApplicationName() <<": Failed to create stock scene." << std::endl;
return 1;
}
std::cout << "Using stock scene instead." << std::endl;
}
else
{
// Run a NodeVisitor to insert OcclusionQueryNodes in the scene graph.
OcclusionQueryVisitor oqv;
root->accept( oqv );
}
bool optimize = arguments.read( "--opt" );
// any option left unread are converted into errors to write out later.
arguments.reportRemainingOptionsAsUnrecognized();
// report any errors if they have occurred when parsing the program arguments.
if (arguments.errors())
{
arguments.writeErrorMessages(std::cout);
return 1;
}
// optimize the scene graph, remove redundant nodes and state etc.
if (optimize)
{
osgUtil::Optimizer optimizer;
optimizer.optimize( root.get() );
}
viewer.setSceneData( root.get() );
KeyHandler* kh = new KeyHandler( *root );
viewer.addEventHandler( kh );
return viewer.run();
}

View File

@ -30,6 +30,7 @@ class LightSource;
class LOD;
class MatrixTransform;
class OccluderNode;
class OcclusionQueryNode;
class PagedLOD;
class PositionAttitudeTransform;
class Projection;
@ -256,6 +257,7 @@ class OSG_EXPORT NodeVisitor : public virtual Referenced
virtual void apply(PagedLOD& node) { apply((LOD&)node); }
virtual void apply(ClearNode& node) { apply((Group&)node); }
virtual void apply(OccluderNode& node) { apply((Group&)node); }
virtual void apply(OcclusionQueryNode& node) { apply((Group&)node); }
/** Callback for managing database paging, such as generated by PagedLOD nodes.*/

View File

@ -0,0 +1,113 @@
//
// Copyright (C) 2007 Skew Matrix Software LLC (http://www.skew-matrix.com)
//
// This library is open source and may be redistributed and/or modified under
// the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
// (at your option) any later version. The full license is in LICENSE file
// included with this distribution, and on the openscenegraph.org website.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// OpenSceneGraph Public License for more details.
//
#ifndef OSG_OCCLUSION_QUERY_NODE
#define OSG_OCCLUSION_QUERY_NODE 1
#include <osg/Export>
#include <osg/CopyOp>
#include <osg/Group>
namespace osg {
// This Node performs occlusion query testing on its children.
// You can use it directly to occlusion query test a portion
// of your scene graph, or you can use it implicitly with an
// OcclusionQueryRoot, which places OcclusionQueryNodes where
// needed and acts as a master control.
class OSG_EXPORT OcclusionQueryNode : public osg::Group
{
public:
OcclusionQueryNode();
// Copy constructor using CopyOp to manage deep vs shallow copy.
OcclusionQueryNode( const OcclusionQueryNode& oqn, const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY );
META_Node( osg, OcclusionQueryNode );
virtual osg::BoundingSphere computeBound() const;
// When disabled, OQN doesn't perform occlusion queries, and simply
// renders its children.
void setQueriesEnabled( bool enable=true );
bool getQueriesEnabled() const { return _enabled; }
// Sets/gets the visibility threshold. If the test indicates that
// the number of visible pixels is less than the specified
// threshold, don't draw the actual geometry.
void setVisibilityThreshold( unsigned int pixels ) { _visThreshold = pixels; }
unsigned int getVisibilityThreshold() const { return _visThreshold; }
// Specifies how many frames to wait before issuing another query.
void setQueryFrameCount( int frames ) { _queryFrameCount = frames; }
int getQueryFrameCount() const { return _queryFrameCount; }
// Indicate whether or not the bounding box used in the occlusion query test
// should be rendered. Handy for debugging and development.
// Should only be called outside of cull/draw. No thread issues.
void setDebugDisplay( bool enable );
bool getDebugDisplay() const;
// Set the StateSets used by the OQN when rendering OQ geometry
// or debug bounding geometry.
void setQueryStateSets( osg::StateSet* ss, osg::StateSet* ssDebug );
// For statistics gathering, e.g., by a NodeVisitor.
bool getPassed() const;
// These methods are public so that osgUtil::CullVisitor can access them.
// Not intended for application use.
bool getPassed( const osg::Camera* camera, float distanceToEyePoint );
void traverseQuery( const osg::Camera* camera, osg::NodeVisitor& nv );
void traverseDebug( osg::NodeVisitor& nv );
protected:
virtual ~OcclusionQueryNode();
void createSupportNodes();
osg::ref_ptr< osg::Geode > _queryGeode;
osg::ref_ptr< osg::Geode > _debugGeode;
bool _enabled;
// Tracks the last frame number that we performed a query.
// User can set how many times (See setQueryFrameCount).
typedef std::map< const osg::Camera*, int > FrameCountMap;
FrameCountMap _frameCountMap;
mutable OpenThreads::Mutex _frameCountMutex;
// For statistics gathering
bool _passed;
// User-settable variables
unsigned int _visThreshold;
int _queryFrameCount;
bool _debugBB;
// Required to ensure that computeBound() is thread-safe.
mutable OpenThreads::Mutex _computeBoundMutex;
};
}
#endif

View File

@ -91,6 +91,7 @@ class OSGUTIL_EXPORT CullVisitor : public osg::NodeVisitor, public osg::CullStac
virtual void apply(osg::ClearNode& node);
virtual void apply(osg::Camera& node);
virtual void apply(osg::OccluderNode& node);
virtual void apply(osg::OcclusionQueryNode& node);
/** Push state set on the current state group.
* If the state exists in a child state group of the current

View File

@ -91,6 +91,7 @@ SET(LIB_PUBLIC_HEADERS
${HEADER_PATH}/Notify
${HEADER_PATH}/Object
${HEADER_PATH}/OccluderNode
${HEADER_PATH}/OcclusionQueryNode
${HEADER_PATH}/OperationThread
${HEADER_PATH}/PagedLOD
${HEADER_PATH}/Plane
@ -247,6 +248,7 @@ ADD_LIBRARY(${LIB_NAME}
Notify.cpp
Object.cpp
OccluderNode.cpp
OcclusionQueryNode.cpp
OperationThread.cpp
PagedLOD.cpp
Point.cpp

View File

@ -0,0 +1,686 @@
//
// Copyright (C) 2007 Skew Matrix Software LLC (http://www.skew-matrix.com)
//
// This library is open source and may be redistributed and/or modified under
// the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
// (at your option) any later version. The full license is in LICENSE file
// included with this distribution, and on the openscenegraph.org website.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// OpenSceneGraph Public License for more details.
//
#include <osg/OcclusionQueryNode>
#include <OpenThreads/ScopedLock>
#include <osg/Timer>
#include <osg/Notify>
#include <osg/CopyOp>
#include <osg/Vec3>
#include <osg/MatrixTransform>
#include <osg/Group>
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/BoundingBox>
#include <osg/BoundingSphere>
#include <osg/Referenced>
#include <osg/ComputeBoundsVisitor>
#include <osg/StateSet>
#include <osg/StateAttribute>
#include <osg/PolygonMode>
#include <osg/ColorMask>
#include <osg/PolygonOffset>
#include <osg/Depth>
#include <map>
#include <vector>
//
// Support classes, used by (and private to) OcclusionQueryNode.
// (Note a lot of this is historical. OcclusionQueryNode formaerly
// existed as a NodeKit outside the core OSG distribution. Many
// of these classes existed in their own separate header and
// source files.)
// Create and return a StateSet appropriate for performing an occlusion
// query test (disable lighting, texture mapping, etc). Probably some
// room for improvement here. Could disable shaders, for example.
osg::StateSet*
initOQState()
{
osg::StateSet* state = new osg::StateSet;
// TBD Possible bug, need to allow user to set render bin number.
state->setRenderBinDetails( 9, "RenderBin" );
state->setMode( GL_LIGHTING, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
state->setTextureMode( 0, GL_TEXTURE_2D, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
state->setMode( GL_CULL_FACE, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::ColorMask* cm = new osg::ColorMask( false, false, false, false );
state->setAttributeAndModes( cm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::Depth* d = new osg::Depth( osg::Depth::LEQUAL, 0.f, 1.f, false );
state->setAttributeAndModes( d, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonMode* pm = new osg::PolygonMode(
osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::FILL );
state->setAttributeAndModes( pm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonOffset* po = new osg::PolygonOffset( -1., -1. );
state->setAttributeAndModes( po, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
return state;
}
// Create and return a StateSet for rendering a debug representation of query geometry.
osg::StateSet*
initOQDebugState()
{
osg::StateSet* debugState = new osg::StateSet;
debugState->setMode( GL_LIGHTING, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
debugState->setTextureMode( 0, GL_TEXTURE_2D, osg::StateAttribute::OFF |
osg::StateAttribute::PROTECTED);
debugState->setMode( GL_CULL_FACE, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonMode* pm = new osg::PolygonMode(
osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::LINE );
debugState->setAttributeAndModes( pm, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
osg::PolygonOffset* po = new osg::PolygonOffset( -1., -1. );
debugState->setAttributeAndModes( po, osg::StateAttribute::ON |
osg::StateAttribute::PROTECTED);
return debugState;
}
// TestResult -- stores (per context) results of an occlusion query
// test performed by QueryGeometry. An OcclusionQueryNode has a
// Geode owning a single QueryGeometry that
// draws the occlusion query geometry. QueryGeometry keeps a
// TestResult per context to store the result/status of each query.
// Accessed during the cull and draw traversals.
class TestResult : public osg::Referenced
{
public:
TestResult() : _init( false ), _id( 0 ), _active( false ), _numPixels( 0 ) {}
~TestResult() {}
bool _init;
// Query ID for this context.
GLuint _id;
// Set to true when a query gets issued and set to
// false when the result is retrieved.
mutable bool _active;
// Result of last query.
GLint _numPixels;
};
// QueryGeometry -- A Drawable that performs an occlusion query,
// using its geometric data as the query geometry.
class QueryGeometry : public osg::Geometry
{
public:
QueryGeometry( const std::string& oqnName=std::string("") );
~QueryGeometry() {}
// TBD implement copy constructor
virtual void drawImplementation( osg::RenderInfo& renderInfo ) const;
unsigned int getNumPixels( const osg::Camera* cam );
protected:
typedef std::map< const osg::Camera*, TestResult > ResultMap;
mutable ResultMap _results;
mutable OpenThreads::Mutex _mapMutex;
// Needed for debug only
std::string _oqnName;
};
struct RetrieveQueriesCallback : public osg::Camera::DrawCallback
{
typedef std::vector<TestResult*> ResultsVector;
ResultsVector _results;
RetrieveQueriesCallback( osg::Drawable::Extensions* ext=NULL )
: _extensionsFallback( ext )
{
}
RetrieveQueriesCallback( const RetrieveQueriesCallback&, const osg::CopyOp& ) {}
META_Object( osgOQ, RetrieveQueriesCallback )
virtual void operator() (const osg::Camera& camera) const
{
if (_results.empty())
return;
const osg::Timer& timer = *osg::Timer::instance();
osg::Timer_t start_tick = timer.tick();
double elapsedTime( 0. );
int count( 0 );
osg::Drawable::Extensions* ext;
if (camera.getGraphicsContext())
{
// The typical path, for osgViewer-based applications or any
// app that has set up a valid GraphicsCOntext for the Camera.
unsigned int contextID = camera.getGraphicsContext()->getState()->getContextID();
RetrieveQueriesCallback* const_this = const_cast<RetrieveQueriesCallback*>( this );
ext = const_this->getExtensions( contextID, true );
}
else
{
// No valid GraphicsContext in the Camera. This might happen in
// SceneView-based apps. Rely on the creating code to have passed
// in a valid Extensions pointer, and hope it's valid for any
// context that might be current.
osg::notify( osg::DEBUG_INFO ) << "osgOQ: RQCB: Using fallback path to obtain Extensions pointer." << std::endl;
ext = _extensionsFallback;
if (!ext)
{
osg::notify( osg::FATAL ) << "osgOQ: RQCB: Extensions pointer fallback is NULL." << std::endl;
return;
}
}
ResultsVector::const_iterator it = _results.begin();
while (it != _results.end())
{
TestResult* tr = const_cast<TestResult*>( *it );
if (!tr->_active || !tr->_init)
{
// This test wasn't executed last frame. This is probably because
// a parent node failed the OQ test, this node is outside the
// view volume, or we didn't run the test because we had not
// exceeded visibleQueryFrameCount.
// Do not obtain results from OpenGL.
it++;
continue;
}
osg::notify( osg::DEBUG_INFO ) <<
"osgOQ: RQCB: Retrieving..." << std::endl;
ext->glGetQueryObjectiv( tr->_id, GL_QUERY_RESULT, &(tr->_numPixels) );
if (tr->_numPixels < 0)
osg::notify( osg::WARN ) << "osgOQ: RQCB: " <<
"glGetQueryObjectiv returned negative value (" << tr->_numPixels << ")." << std::endl;
// Either retrieve last frame's results, or ignore it because the
// camera is inside the view. In either case, _active is now false.
tr->_active = false;
it++;
count++;
}
elapsedTime = timer.delta_s(start_tick,timer.tick());
osg::notify( osg::INFO ) << "osgOQ: RQCB: " << "Retrieved " << count <<
" queries in " << elapsedTime << " seconds." << std::endl;
}
void reset()
{
_results.clear();
}
void add( TestResult* tr )
{
_results.push_back( tr );
}
osg::Drawable::Extensions* getExtensions( unsigned int contextID, bool createIfNotInitalized )
{
if (!s_extensions[ contextID ] && createIfNotInitalized)
s_extensions[ contextID ] = new osg::Drawable::Extensions( contextID );
return s_extensions[ contextID ].get();
}
typedef osg::buffered_value< osg::ref_ptr< osg::Drawable::Extensions > > BufferedExtensions;
static BufferedExtensions s_extensions;
osg::Drawable::Extensions* _extensionsFallback;
};
RetrieveQueriesCallback::BufferedExtensions RetrieveQueriesCallback::s_extensions;
// PreDraw callback; clears the list of Results from the PostDrawCallback (above).
struct ClearQueriesCallback : public osg::Camera::DrawCallback
{
ClearQueriesCallback() : _rqcb( NULL ) {}
ClearQueriesCallback( const ClearQueriesCallback&, const osg::CopyOp& ) {}
META_Object( osgOQ, ClearQueriesCallback )
virtual void operator() (const osg::Camera& camera) const
{
if (!_rqcb)
{
osg::notify( osg::FATAL ) << "oagOQ: CQCB: Invalid RQCB." << std::endl;
return;
}
_rqcb->reset();
}
RetrieveQueriesCallback* _rqcb;
};
QueryGeometry::QueryGeometry( const std::string& oqnName )
: _oqnName( oqnName )
{
// TBD check to see if we can have this on.
setUseDisplayList( false );
}
// After 1.2, param 1 changed from State to RenderInfo.
// Warning: Version was still 1.2 on dev branch long after the 1.2 release,
// and finally got bumped to 1.9 in April 2007.
void
QueryGeometry::drawImplementation( osg::RenderInfo& renderInfo ) const
{
unsigned int contextID = renderInfo.getState()->getContextID();
osg::Drawable::Extensions* ext = getExtensions( contextID, true );
osg::Camera* cam = renderInfo.getCurrentCamera();
// Add callbacks if necessary.
if (!cam->getPostDrawCallback())
{
RetrieveQueriesCallback* rqcb = new RetrieveQueriesCallback( ext );
cam->setPostDrawCallback( rqcb );
ClearQueriesCallback* cqcb = new ClearQueriesCallback;
cqcb->_rqcb = rqcb;
cam->setPreDrawCallback( cqcb );
}
// Get TestResult from Camera map
TestResult* tr;
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock( _mapMutex );
tr = &( _results[ cam ] );
}
// Add TestResult to RQCB.
RetrieveQueriesCallback* rqcb = dynamic_cast<
RetrieveQueriesCallback* >( cam->getPostDrawCallback() );
if (!rqcb)
{
osg::notify( osg::FATAL ) << "oagOQ: QG: Invalid RQCB." << std::endl;
return;
}
rqcb->add( tr );
// Issue query
if (!tr->_init)
{
ext->glGenQueries( 1, &(tr->_id) );
tr->_init = true;
}
osg::notify( osg::DEBUG_INFO ) <<
"oagOQ: QG: Querying for: " << _oqnName << std::endl;
ext->glBeginQuery( GL_SAMPLES_PASSED_ARB, tr->_id );
Geometry::drawImplementation( renderInfo );
ext->glEndQuery( GL_SAMPLES_PASSED_ARB );
tr->_active = true;
osg::notify( osg::DEBUG_INFO ) <<
"osgOQ: QG. OQNName: " << _oqnName <<
", Ctx: " << contextID <<
", ID: " << tr->_id << std::endl;
#ifdef _DEBUG
{
GLenum err;
if ((err = glGetError()) != GL_NO_ERROR)
osg::notify( osg::FATAL ) <<
"osgOQ: QG: OpenGL error: " << err << "." << std::endl;
}
#endif
}
unsigned int
QueryGeometry::getNumPixels( const osg::Camera* cam )
{
TestResult tr;
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock( _mapMutex );
tr = _results[ cam ];
}
return tr._numPixels;
}
// End support classes
//
namespace osg
{
OcclusionQueryNode::OcclusionQueryNode()
: _enabled( true ),
_visThreshold( 500 ),
_queryFrameCount( 5 ),
_debugBB( false )
{
setDataVariance( osg::Object::DYNAMIC );
#if 0
// Before integration into core OSG, OcclusionQueryNode supported a config
// file to override default values. Can't include this in core osg as it
// would introduce a dependency onto osgDB for finding the config file.
// Override defaults if specified in the config file using the OptionLoader singleton.
int clampMe;
if ( OptionLoader::instance()->getOption( "VisibilityThreshold", clampMe ) )
_visThreshold = (clampMe < 0 ) ? 0 : static_cast<unsigned int>( clampMe );
if ( OptionLoader::instance()->getOption( "QueryFrameCount", clampMe ) )
_queryFrameCount = (clampMe < 1) ? 1 : static_cast<unsigned int>( clampMe );
OptionLoader::instance()->getOption( "DebugBoundingVolume", _debugBB );
#endif
// OQN has two Geode member variables, one for doing the
// query and one for rendering the debug geometry.
// Create and initialize them.
createSupportNodes();
}
OcclusionQueryNode::~OcclusionQueryNode()
{
}
OcclusionQueryNode::OcclusionQueryNode( const OcclusionQueryNode& oqn, const osg::CopyOp& copyop )
: Group( oqn, copyop )
{
_enabled = oqn._enabled;
_debugBB = oqn._debugBB;
// Regardless of shallow or deep, create unique support nodes.
createSupportNodes();
}
//PORT-TBD
#if 0
// Currently, retrieves last frame's query results during current frame's cull traversal.
// In the future, should retrive last frame's results immediately after last
// frame's buffer swap.
void
OcclusionQueryNode::traverse( osg::NodeVisitor& nv )
{
if ( !_enabled || (nv.getVisitorType() != osg::NodeVisitor::CULL_VISITOR) )
{
osg::Group::traverse( nv );
return;
}
osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>( &nv );
osg::Camera* camera = cv->getRenderStage()->getCamera();
// In the future, we could hold a reference directly to the QueryDrawable
// to avoid the dynamic_cast.
QueryGeometry* qg = dynamic_cast< QueryGeometry* >( _queryGeode->getDrawable( 0 ) );
if (qg == NULL)
{
osg::notify( osg::FATAL ) <<
"osgOQ: OcclusionQueryNode: No QueryGeometry." << std::endl;
return;
}
// If the distance to the bounding sphere shell is positive, retrieve
// the results. Others (we're inside the BS shell) we are considered
// to have passed and don't need to retrieve the query.
const osg::BoundingSphere& bs = getBound();
float distance = cv->getDistanceToEyePoint( bs._center, false ) - bs._radius;
_passed = ( distance <= 0.f );
if (!_passed)
{
int result = qg->getNumPixels( camera );
_passed = ( (unsigned int)(result) > _visThreshold );
}
if (_passed)
// We're visible. Traverse our children
osg::Group::traverse( nv );
// Submit a new query only if sufficient frames have elapsed.
bool issueQuery;
{
const int curFrame = nv.getTraversalNumber();
OpenThreads::ScopedLock<OpenThreads::Mutex> lock( _frameCountMutex );
int& lastQueryFrame = _frameCountMap[ camera ];
if ( issueQuery = (curFrame - lastQueryFrame >= _queryFrameCount) )
lastQueryFrame = curFrame;
}
if (issueQuery)
_queryGeode->accept( nv );
if (_debugBB)
// If requested, display the debug geometry
_debugGeode->accept( nv );
osg::notify( osg::DEBUG_INFO ) <<
"oagOQ: OQN::traverse: OQN: " << getName() <<
", Cam: " << camera <<
", Passed: " << _passed << std::endl;
}
#endif
bool
OcclusionQueryNode::getPassed( const osg::Camera* camera, float distanceToEyePoint )
{
if ( !_enabled )
// Queries are not enabled. The caller should be osgUtil::CullVisitor,
// return true to traverse the subgraphs.
return true;
// In the future, we could hold a reference directly to the QueryDrawable
// to avoid the dynamic_cast.
QueryGeometry* qg = dynamic_cast< QueryGeometry* >( _queryGeode->getDrawable( 0 ) );
if (qg == NULL)
{
osg::notify( osg::FATAL ) <<
"osgOQ: OcclusionQueryNode: No QueryGeometry." << std::endl;
// Something's broke. Return true so we at least render correctly.
return true;
}
// If the distance to the bounding sphere shell is positive, retrieve
// the results. Others (we're inside the BS shell) we are considered
// to have passed and don't need to retrieve the query.
const osg::BoundingSphere& bs = getBound();
float distance = distanceToEyePoint - bs._radius;
_passed = ( distance <= 0.f );
if (!_passed)
{
int result = qg->getNumPixels( camera );
_passed = ( (unsigned int)(result) > _visThreshold );
}
return _passed;
}
void
OcclusionQueryNode::traverseQuery( const osg::Camera* camera, osg::NodeVisitor& nv )
{
bool issueQuery;
{
const int curFrame = nv.getTraversalNumber();
OpenThreads::ScopedLock<OpenThreads::Mutex> lock( _frameCountMutex );
int& lastQueryFrame = _frameCountMap[ camera ];
if ( issueQuery = (curFrame - lastQueryFrame >= _queryFrameCount) )
lastQueryFrame = curFrame;
}
if (issueQuery)
_queryGeode->accept( nv );
}
void
OcclusionQueryNode::traverseDebug( osg::NodeVisitor& nv )
{
if (_debugBB)
// If requested, display the debug geometry
_debugGeode->accept( nv );
}
osg::BoundingSphere
OcclusionQueryNode::computeBound() const
{
{
// Need to make this routine thread-safe. Typically called by the update
// Visitor, or just after the update traversal, but could be called by
// an application thread or by a non-osgViewer application.
OpenThreads::ScopedLock<OpenThreads::Mutex> lock( _computeBoundMutex ) ;
// This is the logical place to put this code, but the method is const. Cast
// away constness to compute the bounding box and modify the query geometry.
osg::OcclusionQueryNode* nonConstThis = const_cast<osg::OcclusionQueryNode*>( this );
osg::ComputeBoundsVisitor cbv;
nonConstThis->accept( cbv );
osg::BoundingBox bb = cbv.getBoundingBox();
osg::ref_ptr<osg::Vec3Array> v = new osg::Vec3Array;
v->resize( 8 );
(*v)[0] = osg::Vec3( bb._min.x(), bb._min.y(), bb._min.z() );
(*v)[1] = osg::Vec3( bb._max.x(), bb._min.y(), bb._min.z() );
(*v)[2] = osg::Vec3( bb._max.x(), bb._min.y(), bb._max.z() );
(*v)[3] = osg::Vec3( bb._min.x(), bb._min.y(), bb._max.z() );
(*v)[4] = osg::Vec3( bb._max.x(), bb._max.y(), bb._min.z() );
(*v)[5] = osg::Vec3( bb._min.x(), bb._max.y(), bb._min.z() );
(*v)[6] = osg::Vec3( bb._min.x(), bb._max.y(), bb._max.z() );
(*v)[7] = osg::Vec3( bb._max.x(), bb._max.y(), bb._max.z() );
osg::Geometry* geom = dynamic_cast< osg::Geometry* >( nonConstThis->_queryGeode->getDrawable( 0 ) );
geom->setVertexArray( v.get() );
geom = dynamic_cast< osg::Geometry* >( nonConstThis->_debugGeode->getDrawable( 0 ) );
geom->setVertexArray( v.get() );
}
return Group::computeBound();
}
// Should only be called outside of cull/draw. No thread issues.
void
OcclusionQueryNode::setQueriesEnabled( bool enable )
{
_enabled = enable;
}
// Should only be called outside of cull/draw. No thread issues.
void
OcclusionQueryNode::setDebugDisplay( bool debug )
{
_debugBB = debug;
}
bool
OcclusionQueryNode::getDebugDisplay() const
{
return _debugBB;
}
void
OcclusionQueryNode::setQueryStateSets( osg::StateSet* ss, osg::StateSet* ssDebug )
{
if (!_queryGeode.valid() || !_debugGeode.valid())
{
osg::notify( osg::WARN ) << "osgOQ: OcclusionQueryNode:: Invalid support node(s)." << std::endl;
return;
}
_queryGeode->setStateSet( ss );
_debugGeode->setStateSet( ssDebug );
}
bool
OcclusionQueryNode::getPassed() const
{
return _passed;
}
void
OcclusionQueryNode::createSupportNodes()
{
GLushort indices[] = { 0, 1, 2, 3, 4, 5, 6, 7,
0, 3, 6, 5, 2, 1, 4, 7,
5, 4, 1, 0, 2, 7, 6, 3 };
{
// Add the test geometry Geode
_queryGeode = new osg::Geode;
_queryGeode->setName( "OQTest" );
_queryGeode->setDataVariance( osg::Object::DYNAMIC );
osg::ref_ptr< QueryGeometry > geom = new QueryGeometry( getName() );
geom->setDataVariance( osg::Object::DYNAMIC );
geom->addPrimitiveSet( new osg::DrawElementsUShort(
osg::PrimitiveSet::QUADS, 24, indices ) );
_queryGeode->addDrawable( geom.get() );
}
{
// Add a Geode that is a visual representation of the
// test geometry for debugging purposes
_debugGeode = new osg::Geode;
_debugGeode->setName( "Debug" );
_debugGeode->setDataVariance( osg::Object::DYNAMIC );
osg::ref_ptr<osg::Geometry> geom = new osg::Geometry;
geom->setDataVariance( osg::Object::DYNAMIC );
osg::ref_ptr<osg::Vec4Array> ca = new osg::Vec4Array;
ca->push_back( osg::Vec4( 1.f, 1.f, 1.f, 1.f ) );
geom->setColorArray( ca.get() );
geom->setColorBinding( osg::Geometry::BIND_OVERALL );
geom->addPrimitiveSet( new osg::DrawElementsUShort(
osg::PrimitiveSet::QUADS, 24, indices ) );
_debugGeode->addDrawable( geom.get() );
}
// Creste state sets. Note that the osgOQ visitors (which place OQNs throughout
// the scene graph) create a single instance of these StateSets shared
// between all OQNs for efficiency.
setQueryStateSets( initOQState(), initOQDebugState() );
}
}

View File

@ -42,6 +42,7 @@ Node.cpp
NodeCallback.cpp
Object.cpp
OccluderNode.cpp
OcclusionQueryNode.cpp
PagedLOD.cpp
Point.cpp
PointSprite.cpp

View File

@ -19,6 +19,7 @@
#include <osg/ClipNode>
#include <osg/TexGenNode>
#include <osg/OccluderNode>
#include <osg/OcclusionQueryNode>
#include <osg/Notify>
#include <osg/TexEnv>
#include <osg/AlphaFunc>
@ -1392,5 +1393,34 @@ void CullVisitor::apply(osg::OccluderNode& node)
popOccludersCurrentMask(_nodePath);
}
void CullVisitor::apply(osg::OcclusionQueryNode& node)
{
if (isCulled(node)) return;
// push the culling mode.
pushCurrentMask();
// push the node's state.
StateSet* node_state = node.getStateSet();
if (node_state) pushStateSet(node_state);
osg::Camera* camera = getRenderStage()->getCamera();
// If previous query indicates visible, then traverse as usual.
if (node.getPassed( camera, getDistanceToEyePoint( node.getBound()._center, false ) ))
handle_cull_callbacks_and_traverse(node);
// Traverse the query subtree if OcclusionQueryNode needs to issue another query.
node.traverseQuery( camera, *this );
// Traverse the debug bounding geometry, if enabled.
node.traverseDebug( *this );
// pop the node's state off the render graph stack.
if (node_state) popStateSet();
// pop the culling mode.
popCurrentMask();
}