/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program 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 GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.

You may alternatively use this source under the terms of a specific version of
the OGRE Unrestricted License provided you have obtained such a license from
Torus Knot Software Ltd.
-----------------------------------------------------------------------------
*/
#include "OgreBspSceneManager.h"
#include "OgreBspResourceManager.h"
#include "OgreBspNode.h"
#include "OgreException.h"
#include "OgreRenderSystem.h"
#include "OgreCamera.h"
#include "OgreMaterial.h"
#include "OgrePatchSurface.h"
#include "OgreMesh.h"
#include "OgreSubMesh.h"
#include "OgreMath.h"
#include "OgreControllerManager.h"
#include "OgreLogManager.h"
#include "OgreBspSceneNode.h"
#include "OgreStringConverter.h"
#include "OgreLogManager.h"
#include "OgreTechnique.h"
#include "OgrePass.h"
#include "OgreMaterialManager.h"


#include <fstream>

namespace Ogre {

    //-----------------------------------------------------------------------
    BspSceneManager::BspSceneManager(const String& name)
		: SceneManager(name)
    {
        // Set features for debugging render
        mShowNodeAABs = false;

        // No sky by default
        mSkyPlaneEnabled = false;
        mSkyBoxEnabled = false;
        mSkyDomeEnabled = false;

        mLevel.setNull();

    }
	//-----------------------------------------------------------------------
	const String& BspSceneManager::getTypeName(void) const
	{
		return BspSceneManagerFactory::FACTORY_TYPE_NAME;
	}
    //-----------------------------------------------------------------------
    BspSceneManager::~BspSceneManager()
    {
        freeMemory();
        mLevel.setNull();
    }
    //-----------------------------------------------------------------------
    size_t BspSceneManager::estimateWorldGeometry(const String& filename)
    {
        return BspLevel::calculateLoadingStages(filename);
        
    }
    //-----------------------------------------------------------------------
    size_t BspSceneManager::estimateWorldGeometry(DataStreamPtr& stream, 
		const String& typeName)
    {
        return BspLevel::calculateLoadingStages(stream);
        
    }
    //-----------------------------------------------------------------------
    void BspSceneManager::setWorldGeometry(const String& filename)
    {
        mLevel.setNull();
        // Check extension is .bsp
        char extension[6];
        size_t pos = filename.find_last_of(".");
		if( pos == String::npos )
            OGRE_EXCEPT(
				Exception::ERR_INVALIDPARAMS,
                "Unable to load world geometry. Invalid extension (must be .bsp).",
                "BspSceneManager::setWorldGeometry");

        strncpy(extension, filename.substr(pos + 1, filename.length() - pos).c_str(), 5);
		extension[5] = 0;

        if (stricmp(extension, "bsp"))
            OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS,
			"Unable to load world geometry. Invalid extension (must be .bsp).",
            "BspSceneManager::setWorldGeometry");

        // Load using resource manager
        mLevel = BspResourceManager::getSingleton().load(filename, 
            ResourceGroupManager::getSingleton().getWorldResourceGroupName());

		if (mLevel->isSkyEnabled())
		{
			// Quake3 is always aligned with Z upwards
			Quaternion q;
			q.FromAngleAxis(Radian(Math::HALF_PI), Vector3::UNIT_X);
			// Also draw last, and make close to camera (far clip plane is shorter)
			setSkyDome(true, mLevel->getSkyMaterialName(),
				mLevel->getSkyCurvature(), 12, 2000, false, q);
		}
		else
		{
			setSkyDome(false, StringUtil::BLANK);
		}

        // Init static render operation
        mRenderOp.vertexData = mLevel->mVertexData;
        // index data is per-frame
        mRenderOp.indexData = OGRE_NEW IndexData();
        mRenderOp.indexData->indexStart = 0;
        mRenderOp.indexData->indexCount = 0;
        // Create enough index space to render whole level
        mRenderOp.indexData->indexBuffer = HardwareBufferManager::getSingleton()
            .createIndexBuffer(
                HardwareIndexBuffer::IT_32BIT, // always 32-bit
                mLevel->mNumIndexes, 
                HardwareBuffer::HBU_DYNAMIC_WRITE_ONLY_DISCARDABLE, false);

        mRenderOp.operationType = RenderOperation::OT_TRIANGLE_LIST;
        mRenderOp.useIndexes = true;


    }
    //-----------------------------------------------------------------------
    void BspSceneManager::setWorldGeometry(DataStreamPtr& stream, 
		const String& typeName)
    {
        mLevel.setNull();

        // Load using resource manager
        mLevel = BspResourceManager::getSingleton().load(stream, 
			ResourceGroupManager::getSingleton().getWorldResourceGroupName());

		if (mLevel->isSkyEnabled())
		{
			// Quake3 is always aligned with Z upwards
			Quaternion q;
			q.FromAngleAxis(Radian(Math::HALF_PI), Vector3::UNIT_X);
			// Also draw last, and make close to camera (far clip plane is shorter)
			setSkyDome(true, mLevel->getSkyMaterialName(),
				mLevel->getSkyCurvature(), 12, 2000, false, q);
		}
		else
		{
			setSkyDome(false, StringUtil::BLANK);
		}

        // Init static render operation
        mRenderOp.vertexData = mLevel->mVertexData;
        // index data is per-frame
        mRenderOp.indexData = OGRE_NEW IndexData();
        mRenderOp.indexData->indexStart = 0;
        mRenderOp.indexData->indexCount = 0;
        // Create enough index space to render whole level
        mRenderOp.indexData->indexBuffer = HardwareBufferManager::getSingleton()
            .createIndexBuffer(
                HardwareIndexBuffer::IT_32BIT, // always 32-bit
                mLevel->mNumIndexes, 
                HardwareBuffer::HBU_DYNAMIC_WRITE_ONLY_DISCARDABLE, false);

        mRenderOp.operationType = RenderOperation::OT_TRIANGLE_LIST;
        mRenderOp.useIndexes = true;


    }
    //-----------------------------------------------------------------------
    void BspSceneManager::_findVisibleObjects(Camera* cam, 
		VisibleObjectsBoundsInfo* visibleBounds, bool onlyShadowCasters)
    {
        // Clear unique list of movables for this frame
        mMovablesForRendering.clear();

		// Assemble an AAB on the fly which contains the scene elements visible
		// by the camera.
		CamVisibleObjectsMap::iterator findIt = mCamVisibleObjectsMap.find( cam );

        // Walk the tree, tag static geometry, return camera's node (for info only)
        // Movables are now added to the render queue in processVisibleLeaf
        walkTree(cam, &(findIt->second), onlyShadowCasters);
    }
	//---------------------------------------------------------------------
	bool BspSceneManager::fireRenderQueueEnded(uint8 id, const String& invocation)
	{
		bool repeat = SceneManager::fireRenderQueueEnded(id, invocation);
		// Trigger level render just after skies
		// can't trigger on mWorldGeometryRenderQueue because we're not queueing there
		if (id == RENDER_QUEUE_SKIES_EARLY)
		{
			renderStaticGeometry();
		}
		return repeat;

	}
    //-----------------------------------------------------------------------
    void BspSceneManager::renderStaticGeometry(void)
    {
		// Check we should be rendering
		if (!isRenderQueueToBeProcessed(mWorldGeometryRenderQueue))
			return;

        // Cache vertex/face data first
        std::vector<StaticFaceGroup*>::const_iterator faceGrpi;
        static RenderOperation patchOp;
        
        // no world transform required
        mDestRenderSystem->_setWorldMatrix(Matrix4::IDENTITY);
        // Set view / proj
        mDestRenderSystem->_setViewMatrix(mCachedViewMatrix);
        mDestRenderSystem->_setProjectionMatrix(mCameraInProgress->getProjectionMatrixRS());

        // For each material in turn, cache rendering data & render
        MaterialFaceGroupMap::const_iterator mati;

        for (mati = mMatFaceGroupMap.begin(); mati != mMatFaceGroupMap.end(); ++mati)
        {
            // Get Material
            Material* thisMaterial = mati->first;

            // Empty existing cache
            mRenderOp.indexData->indexCount = 0;
            // lock index buffer ready to receive data
            unsigned int* pIdx = static_cast<unsigned int*>(
                mRenderOp.indexData->indexBuffer->lock(HardwareBuffer::HBL_DISCARD));

            for (faceGrpi = mati->second.begin(); faceGrpi != mati->second.end(); ++faceGrpi)
            {
                // Cache each
                unsigned int numelems = cacheGeometry(pIdx, *faceGrpi);
                mRenderOp.indexData->indexCount += numelems;
                pIdx += numelems;
            }
            // Unlock the buffer
            mRenderOp.indexData->indexBuffer->unlock();

            // Skip if no faces to process (we're not doing flare types yet)
            if (mRenderOp.indexData->indexCount == 0)
                continue;

            Technique::PassIterator pit = thisMaterial->getTechnique(0)->getPassIterator();

            while (pit.hasMoreElements())
            {
                _setPass(pit.getNext());

                mDestRenderSystem->_render(mRenderOp);


            } 


        } // for each material

        /*
        if (mShowNodeAABs)
        {
            mDestRenderSystem->_render(mAABGeometry);
        }
        */
    }
    //-----------------------------------------------------------------------
    // REMOVE THIS CRAP
    //-----------------------------------------------------------------------
    // Temp debug lines
    bool firstTime = true;
    std::ofstream of;
    //-----------------------------------------------------------------------
    //-----------------------------------------------------------------------
    //-----------------------------------------------------------------------
    BspNode* BspSceneManager::walkTree(Camera* camera, 
		VisibleObjectsBoundsInfo *visibleBounds, bool onlyShadowCasters)
    {
		if (mLevel.isNull()) return 0;

        // Locate the leaf node where the camera is located
        BspNode* cameraNode = mLevel->findLeaf(camera->getDerivedPosition());

        mMatFaceGroupMap.clear();
        mFaceGroupSet.clear();

        // Scan through all the other leaf nodes looking for visibles
        int i = mLevel->mNumNodes - mLevel->mLeafStart;
        BspNode* nd = mLevel->mRootNode + mLevel->mLeafStart;

        /*
        if (firstTime)
        {
            camera->getViewMatrix(); // Force update view before report
            of.open("BspSceneManager.log");
            of << *camera << std::endl;
            of << "Camera Node: " << *cameraNode << std::endl;
            of << "Vertex Data: " << std::endl;
            for (int testi = 0; testi < mLevel->mNumVertices; ++testi)
            {
                of << " " << testi << ": pos(" <<
                  mLevel->mVertices[testi].position[0] << ", " <<
                    mLevel->mVertices[testi].position[1] << ", " << mLevel->mVertices[testi].position[2] << ")" <<
                    " uv(" << mLevel->mVertices[testi].texcoords[0] << ", " << mLevel->mVertices[testi].texcoords[1] << ")" <<
                    " lm(" << mLevel->mVertices[testi].lightmap[0] << ", " << mLevel->mVertices[testi].lightmap[1] << ")" << std::endl;
            }
            of << "Element data:" << std::endl;
            for (testi = 0; testi < mLevel->mNumElements; ++testi)
            {
                of << " " << testi << ": " << mLevel->mElements[testi] << std::endl;

            }
        }
        */

        while (i--)
        {
            if (mLevel->isLeafVisible(cameraNode, nd))
            {

                // Visible according to PVS, check bounding box against frustum
                FrustumPlane plane;
                if (camera->isVisible(nd->getBoundingBox(), &plane))
                {
                    //if (firstTime)
                    //{
                    //    of << "Visible Node: " << *nd << std::endl;
                    //}
                    processVisibleLeaf(nd, camera, visibleBounds, onlyShadowCasters);
                    if (mShowNodeAABs)
                        addBoundingBox(nd->getBoundingBox(), true);
                }
            }
            nd++;
        }


        // TEST
        //if (firstTime)
        //{
        //    of.close();
        //    firstTime = false;
        //}
        return cameraNode;

    }
    //-----------------------------------------------------------------------
    void BspSceneManager::processVisibleLeaf(BspNode* leaf, Camera* cam, 
		VisibleObjectsBoundsInfo* visibleBounds, bool onlyShadowCasters)
    {
        MaterialPtr pMat;
        // Skip world geometry if we're only supposed to process shadow casters
        // World is pre-lit
        if (!onlyShadowCasters)
        {
            // Parse the leaf node's faces, add face groups to material map
            int numGroups = leaf->getNumFaceGroups();
            int idx = leaf->getFaceGroupStart();

            while (numGroups--)
            {
                int realIndex = mLevel->mLeafFaceGroups[idx++];
                // Check not already included
                if (mFaceGroupSet.find(realIndex) != mFaceGroupSet.end())
                    continue;
                StaticFaceGroup* faceGroup = mLevel->mFaceGroups + realIndex;
                // Get Material pointer by handle
                pMat = MaterialManager::getSingleton().getByHandle(faceGroup->materialHandle);
                assert (!pMat.isNull());
                // Check normal (manual culling)
                ManualCullingMode cullMode = pMat->getTechnique(0)->getPass(0)->getManualCullingMode();
                if (cullMode != MANUAL_CULL_NONE)
                {
                    Real dist = faceGroup->plane.getDistance(cam->getDerivedPosition());
                    if ( (dist < 0 && cullMode == MANUAL_CULL_BACK) ||
                        (dist > 0 && cullMode == MANUAL_CULL_FRONT) )
                        continue; // skip
                }
                mFaceGroupSet.insert(realIndex);
                // Try to insert, will find existing if already there
                std::pair<MaterialFaceGroupMap::iterator, bool> matgrpi;
                matgrpi = mMatFaceGroupMap.insert(
                    MaterialFaceGroupMap::value_type(pMat.getPointer(), std::vector<StaticFaceGroup*>())
                    );
                // Whatever happened, matgrpi.first is map iterator
                // Need to get second part of that to get vector
                matgrpi.first->second.push_back(faceGroup);

                //if (firstTime)
                //{
                //    of << "  Emitting faceGroup: index=" << realIndex << ", " << *faceGroup << std::endl;
                //}
            }
        }

        // Add movables to render queue, provided it hasn't been seen already
        const BspNode::IntersectingObjectSet& objects = leaf->getObjects();
        BspNode::IntersectingObjectSet::const_iterator oi, oiend;
        oiend = objects.end();
        for (oi = objects.begin(); oi != oiend; ++oi)
        {
            if (mMovablesForRendering.find(*oi) == mMovablesForRendering.end())
            {
                // It hasn't been seen yet
                MovableObject *mov = const_cast<MovableObject*>(*oi); // hacky
                if (mov->isVisible() && 
                    (!onlyShadowCasters || mov->getCastShadows()) && 
					cam->isVisible(mov->getWorldBoundingBox()))
                {
                    mov->_notifyCurrentCamera(cam);
                    mov->_updateRenderQueue(getRenderQueue());
                    // Check if the bounding box should be shown.
                    SceneNode* sn = static_cast<SceneNode*>(mov->getParentNode());
                    if (sn->getShowBoundingBox() || mShowBoundingBoxes)
                    {
                        sn->_addBoundingBoxToQueue(getRenderQueue());
                    }
                    mMovablesForRendering.insert(*oi);

					// update visible boundaries aab
					if (visibleBounds)
					{
						visibleBounds->merge((*oi)->getWorldBoundingBox(true), 
							(*oi)->getWorldBoundingSphere(true), cam);
					}
                }

            }
        }


    }
    //-----------------------------------------------------------------------
    unsigned int BspSceneManager::cacheGeometry(unsigned int* pIndexes, 
        const StaticFaceGroup* faceGroup)
    {
        // Skip sky always
        if (faceGroup->isSky)
            return 0;

        size_t idxStart, numIdx, vertexStart;

        if (faceGroup->fType == FGT_FACE_LIST)
        {
            idxStart = faceGroup->elementStart;
            numIdx = faceGroup->numElements;
            vertexStart = faceGroup->vertexStart;
        }
        else if (faceGroup->fType == FGT_PATCH)
        {

            idxStart = faceGroup->patchSurf->getIndexOffset();
            numIdx = faceGroup->patchSurf->getCurrentIndexCount();
            vertexStart = faceGroup->patchSurf->getVertexOffset();
        }
		else
		{
			// Unsupported face type
			return 0;
		}


        // Copy index data
        unsigned int* pSrc = static_cast<unsigned int*>(
            mLevel->mIndexes->lock(
                idxStart * sizeof(unsigned int),
                numIdx * sizeof(unsigned int), 
                HardwareBuffer::HBL_READ_ONLY));
        // Offset the indexes here
        // we have to do this now rather than up-front because the 
        // indexes are sometimes reused to address different vertex chunks
        for (size_t elem = 0; elem < numIdx; ++elem)
        {
            *pIndexes++ = *pSrc++ + vertexStart;
        }
        mLevel->mIndexes->unlock();

        // return number of elements
        return static_cast<unsigned int>(numIdx);


    }

    //-----------------------------------------------------------------------
    void BspSceneManager::freeMemory(void)
    {
        // no need to delete index buffer, will be handled by shared pointer
        OGRE_DELETE mRenderOp.indexData;
		mRenderOp.indexData = 0;
    }
    //-----------------------------------------------------------------------
    void BspSceneManager::showNodeBoxes(bool show)
    {
        mShowNodeAABs = show;
    }
    //-----------------------------------------------------------------------
    void BspSceneManager::addBoundingBox(const AxisAlignedBox& aab, bool visible)
    {
        /*
        unsigned long visibleColour;
        unsigned long nonVisibleColour;
        Root& r = Root::getSingleton();

        r.convertColourValue(ColourValue::White, &visibleColour);
        r.convertColourValue(ColourValue::Blue, &nonVisibleColour);
        if (mShowNodeAABs)
        {
            // Add set of lines
            float* pVertices = (float*)mAABGeometry.pVertices + (mAABGeometry.numVertices*3);
            unsigned short* pIndexes = mAABGeometry.pIndexes + mAABGeometry.numIndexes;
            unsigned long* pColours = (unsigned long*)mAABGeometry.pDiffuseColour + mAABGeometry.numVertices;

            const Vector3* pCorner = aab.getAllCorners();

            int i;
            for (i = 0; i < 8; ++i)
            {
                *pVertices++ = pCorner->x;
                *pVertices++ = pCorner->y;
                *pVertices++ = pCorner->z;
                pCorner++;

                if (visible)
                {
                    *pColours++ = visibleColour;
                }
                else
                {
                    *pColours++ = nonVisibleColour;
                }

            }

            *pIndexes++ = 0 + mAABGeometry.numVertices;
            *pIndexes++ = 1 + mAABGeometry.numVertices;
            *pIndexes++ = 1 + mAABGeometry.numVertices;
            *pIndexes++ = 2 + mAABGeometry.numVertices;
            *pIndexes++ = 2 + mAABGeometry.numVertices;
            *pIndexes++ = 3 + mAABGeometry.numVertices;
            *pIndexes++ = 3 + mAABGeometry.numVertices;
            *pIndexes++ = 1 + mAABGeometry.numVertices;
            *pIndexes++ = 4 + mAABGeometry.numVertices;
            *pIndexes++ = 5 + mAABGeometry.numVertices;
            *pIndexes++ = 5 + mAABGeometry.numVertices;
            *pIndexes++ = 6 + mAABGeometry.numVertices;
            *pIndexes++ = 6 + mAABGeometry.numVertices;
            *pIndexes++ = 7 + mAABGeometry.numVertices;
            *pIndexes++ = 7 + mAABGeometry.numVertices;
            *pIndexes++ = 4 + mAABGeometry.numVertices;
            *pIndexes++ = 1 + mAABGeometry.numVertices;
            *pIndexes++ = 5 + mAABGeometry.numVertices;
            *pIndexes++ = 2 + mAABGeometry.numVertices;
            *pIndexes++ = 4 + mAABGeometry.numVertices;
            *pIndexes++ = 0 + mAABGeometry.numVertices;
            *pIndexes++ = 6 + mAABGeometry.numVertices;
            *pIndexes++ = 3 + mAABGeometry.numVertices;
            *pIndexes++ = 7 + mAABGeometry.numVertices;


            mAABGeometry.numVertices += 8;
            mAABGeometry.numIndexes += 24;


        }
        */

    }
    //-----------------------------------------------------------------------
    ViewPoint BspSceneManager::getSuggestedViewpoint(bool random)
    {
        if (mLevel.isNull() || mLevel->mPlayerStarts.size() == 0)
        {
            // No level, use default
            return SceneManager::getSuggestedViewpoint(random);
        }
        else
        {
            if (random)
            {
                size_t idx = (size_t)( Math::UnitRandom() * mLevel->mPlayerStarts.size() );
                return mLevel->mPlayerStarts[idx];
            }
            else
            {
                return mLevel->mPlayerStarts[0];
            }


        }

    }
    //-----------------------------------------------------------------------
    SceneNode * BspSceneManager::createSceneNodeImpl( void )
    {
        return OGRE_NEW BspSceneNode( this );
    }
    //-----------------------------------------------------------------------
    SceneNode * BspSceneManager::createSceneNodeImpl( const String &name )
    {
        return OGRE_NEW BspSceneNode( this, name );
    }
    //-----------------------------------------------------------------------
    void BspSceneManager::_notifyObjectMoved(const MovableObject* mov, 
        const Vector3& pos)
    {
		if (!mLevel.isNull())
		{
			mLevel->_notifyObjectMoved(mov, pos);
		}
    }
    //-----------------------------------------------------------------------
	void BspSceneManager::_notifyObjectDetached(const MovableObject* mov)
	{
		if (!mLevel.isNull())
		{
			mLevel->_notifyObjectDetached(mov);
		}
	}
	//-----------------------------------------------------------------------
	void BspSceneManager::clearScene(void)
	{
		SceneManager::clearScene();
		freeMemory();
		// Clear level
		mLevel.setNull();
	}
    //-----------------------------------------------------------------------
    /*
    AxisAlignedBoxSceneQuery* BspSceneManager::
    createAABBQuery(const AxisAlignedBox& box, unsigned long mask)
    {
        // TODO
        return NULL;
    }
    //-----------------------------------------------------------------------
    SphereSceneQuery* BspSceneManager::
    createSphereQuery(const Sphere& sphere, unsigned long mask)
    {
        // TODO
        return NULL;
    }
    */
    //-----------------------------------------------------------------------
    RaySceneQuery* BspSceneManager::
    createRayQuery(const Ray& ray, unsigned long mask)
    {
        BspRaySceneQuery* q = OGRE_NEW BspRaySceneQuery(this);
        q->setRay(ray);
        q->setQueryMask(mask);
        return q;
    }
    //-----------------------------------------------------------------------
    IntersectionSceneQuery* BspSceneManager::
    createIntersectionQuery(unsigned long mask)
    {
        BspIntersectionSceneQuery* q = OGRE_NEW BspIntersectionSceneQuery(this);
        q->setQueryMask(mask);
        return q;
    }
    //-----------------------------------------------------------------------
    //-----------------------------------------------------------------------
    BspIntersectionSceneQuery::BspIntersectionSceneQuery(SceneManager* creator) 
        : DefaultIntersectionSceneQuery(creator)
    {
        // Add bounds fragment type
        mSupportedWorldFragments.insert(SceneQuery::WFT_PLANE_BOUNDED_REGION);
        
    }
    void BspIntersectionSceneQuery::execute(IntersectionSceneQueryListener* listener)
    {
        /*
        Go through each leaf node in BspLevel and check movables against each other and world
        Issue: some movable-movable intersections could be reported twice if 2 movables
        overlap 2 leaves?
        */
        const BspLevelPtr& lvl = ((BspSceneManager*)mParentSceneMgr)->getLevel();
		if (lvl.isNull()) return;

        BspNode* leaf = lvl->getLeafStart();
        int numLeaves = lvl->getNumLeaves();
        
        while (numLeaves--)
        {
            const BspNode::IntersectingObjectSet& objects = leaf->getObjects();
            int numObjects = (int)objects.size();

            BspNode::IntersectingObjectSet::const_iterator a, b, theEnd;
            theEnd = objects.end();
            a = objects.begin();
            for (int oi = 0; oi < numObjects; ++oi, ++a)
            {
                const MovableObject* aObj = *a;
                // Skip this object if collision not enabled
                if (!(aObj->getQueryFlags() & mQueryMask) ||
					!(aObj->getTypeFlags() & mQueryTypeMask) ||
					!aObj->isInScene())
                    continue;

                if (oi < (numObjects-1))
                {
                    // Check object against others in this node
                    b = a;
                    for (++b; b != theEnd; ++b)
                    {
                        const MovableObject* bObj = *b;
                        // Apply mask to b (both must pass)
                        if ((bObj->getQueryFlags() & mQueryMask) && 
							(bObj->getTypeFlags() & mQueryTypeMask) && 
							bObj->isInScene())
                        {
                            const AxisAlignedBox& box1 = aObj->getWorldBoundingBox();
                            const AxisAlignedBox& box2 = bObj->getWorldBoundingBox();

                            if (box1.intersects(box2))
                            {
                                if (!listener->queryResult(const_cast<MovableObject*>(aObj), 
                                    const_cast<MovableObject*>(bObj)))
									return; 
                            }
                        }
                    }
                }
                // Check object against brushes
                if (mQueryTypeMask & SceneManager::WORLD_GEOMETRY_TYPE_MASK)
                {
                    const BspNode::NodeBrushList& brushes = leaf->getSolidBrushes();
                    BspNode::NodeBrushList::const_iterator bi, biend;
                    biend = brushes.end();
                    Real radius = aObj->getBoundingRadius();
                    const Vector3& pos = aObj->getParentNode()->_getDerivedPosition();

                    for (bi = brushes.begin(); bi != biend; ++bi)
                    {
                        std::list<Plane>::const_iterator planeit, planeitend;
                        planeitend = (*bi)->planes.end();
                        bool brushIntersect = true; // Assume intersecting for now

                        for (planeit = (*bi)->planes.begin(); planeit != planeitend; ++planeit)
                        {
                            Real dist = planeit->getDistance(pos);
                            if (dist > radius)
                            {
                                // Definitely excluded
                                brushIntersect = false;
                                break;
                            }
                        }
                        if (brushIntersect)
                        {
                            // report this brush as it's WorldFragment
                            assert((*bi)->fragment.fragmentType == SceneQuery::WFT_PLANE_BOUNDED_REGION);
                            if (!listener->queryResult(const_cast<MovableObject*>(aObj), 
                                    const_cast<WorldFragment*>(&((*bi)->fragment))))
								return; 
                        }

                    }
                }


            }

            ++leaf;
        }



    }
    //-----------------------------------------------------------------------
    //-----------------------------------------------------------------------
    BspRaySceneQuery::BspRaySceneQuery(SceneManager* creator)
        :DefaultRaySceneQuery(creator)
    {
        // Add supported fragment types
        mSupportedWorldFragments.insert(SceneQuery::WFT_SINGLE_INTERSECTION);
        mSupportedWorldFragments.insert(SceneQuery::WFT_PLANE_BOUNDED_REGION);
    }
    //-----------------------------------------------------------------------
    void BspRaySceneQuery::execute(RaySceneQueryListener* listener)
    {
        clearTemporaries();
		BspLevelPtr lvl = static_cast<BspSceneManager*>(mParentSceneMgr)->getLevel();
		if (!lvl.isNull())
		{
			processNode(
				lvl->getRootNode(), 
				mRay, listener);
		}
    }
    //-----------------------------------------------------------------------
    BspRaySceneQuery::~BspRaySceneQuery()
    {
        clearTemporaries();
    }
    //-----------------------------------------------------------------------
    void BspRaySceneQuery::clearTemporaries(void)
    {
        mObjsThisQuery.clear();
        std::vector<WorldFragment*>::iterator i;
        for (i = mSingleIntersections.begin(); i != mSingleIntersections.end(); ++i)
        {
            OGRE_FREE(*i, MEMCATEGORY_SCENE_CONTROL);
        }
        mSingleIntersections.clear();
    }
    //-----------------------------------------------------------------------
    bool BspRaySceneQuery::processNode(const BspNode* node, const Ray& tracingRay, 
        RaySceneQueryListener* listener, Real maxDistance, Real traceDistance)
    {
        if (node->isLeaf())
        {
            return processLeaf(node, tracingRay, listener, maxDistance, traceDistance);
        }

        bool res = true;
        std::pair<bool, Real> result = tracingRay.intersects(node->getSplitPlane());
        if (result.first && result.second < maxDistance)
        {
            // Crosses the split plane, need to perform 2 queries
            // Calculate split point ray
            Vector3 splitPoint = tracingRay.getOrigin() 
                + tracingRay.getDirection() * result.second;
            Ray splitRay(splitPoint, tracingRay.getDirection());

            if (node->getSide(tracingRay.getOrigin()) == Plane::NEGATIVE_SIDE)
            {
                // Intersects from -ve side, so do back then front
                res = processNode(
                    node->getBack(), tracingRay, listener, result.second, traceDistance);
                if (!res) return res;
                
                res = processNode(
                    node->getFront(), splitRay, listener, 
                    maxDistance - result.second, 
                    traceDistance + result.second);
            }
            else
            {
                // Intersects from +ve side, so do front then back
                res = processNode(node->getFront(), tracingRay, listener, 
                    result.second, traceDistance);
                if (!res) return res;
                res = processNode(node->getBack(), splitRay, listener,
                    maxDistance - result.second, 
                    traceDistance + result.second);
            }
        }
        else
        {
            // Does not cross the splitting plane, just cascade down one side
            res = processNode(node->getNextNode(tracingRay.getOrigin()),
                tracingRay, listener, maxDistance, traceDistance);
        }

        return res;
    }
    //-----------------------------------------------------------------------
    bool BspRaySceneQuery::processLeaf(const BspNode* leaf, const Ray& tracingRay, 
        RaySceneQueryListener* listener, Real maxDistance, Real traceDistance)
    {
        const BspNode::IntersectingObjectSet& objects = leaf->getObjects();

        BspNode::IntersectingObjectSet::const_iterator i, iend;
        iend = objects.end();
        //Check ray against objects
        for(i = objects.begin(); i != iend; ++i)
        {
            // cast away constness, constness of node is nothing to do with objects
            MovableObject* obj = const_cast<MovableObject*>(*i);
            // Skip this object if not enabled
            if(!(obj->getQueryFlags() & mQueryMask) ||
				!((obj->getTypeFlags() & mQueryTypeMask)))
                continue;

            // check we haven't reported this one already
            // (objects can be intersecting more than one node)
            if (mObjsThisQuery.find(obj) != mObjsThisQuery.end())
                continue;

            //Test object as bounding box
            std::pair<bool, Real> result = 
                tracingRay.intersects(obj->getWorldBoundingBox());
            // if the result came back positive and intersection point is inside
            // the node, fire the event handler
            if(result.first && result.second <= maxDistance)
            {
                if (!listener->queryResult(obj, result.second + traceDistance))
					return false;
            }
        }


        // Check ray against brushes
        if (mQueryTypeMask & SceneManager::WORLD_GEOMETRY_TYPE_MASK)
        {
            const BspNode::NodeBrushList& brushList = leaf->getSolidBrushes();
            BspNode::NodeBrushList::const_iterator bi, biend;
            biend = brushList.end();
            bool intersectedBrush = false;
            for (bi = brushList.begin(); bi != biend; ++bi)
            {
                BspNode::Brush* brush = *bi;
                

                std::pair<bool, Real> result = Math::intersects(tracingRay, brush->planes, true);
                // if the result came back positive and intersection point is inside
                // the node, check if this brush is closer
                if(result.first && result.second <= maxDistance)
                {
                    intersectedBrush = true;
                    if(mWorldFragmentType == SceneQuery::WFT_SINGLE_INTERSECTION)
                    {
                        // We're interested in a single intersection
                        // Have to create these 
                        SceneQuery::WorldFragment* wf = OGRE_ALLOC_T(SceneQuery::WorldFragment, 1, MEMCATEGORY_SCENE_CONTROL);
                        wf->fragmentType = SceneQuery::WFT_SINGLE_INTERSECTION;
                        wf->singleIntersection = tracingRay.getPoint(result.second);
                        // save this so we can clean up later
                        mSingleIntersections.push_back(wf);
                        if (!listener->queryResult(wf, result.second + traceDistance))
							return false;
                    }
                    else if (mWorldFragmentType ==  SceneQuery::WFT_PLANE_BOUNDED_REGION)
                    {
                        // We want the whole bounded volume
                        assert((*bi)->fragment.fragmentType == SceneQuery::WFT_PLANE_BOUNDED_REGION);
                        if (!listener->queryResult(const_cast<WorldFragment*>(&(brush->fragment)), 
                            result.second + traceDistance))
							return false; 

                    }
                }
            }
            if (intersectedBrush)
            {
                return false; // stop here
            }
        }

        return true;

    } 
    //-----------------------------------------------------------------------
	//-----------------------------------------------------------------------
	const String BspSceneManagerFactory::FACTORY_TYPE_NAME = "BspSceneManager";
	//-----------------------------------------------------------------------
	void BspSceneManagerFactory::initMetaData(void) const
	{
		mMetaData.typeName = FACTORY_TYPE_NAME;
		mMetaData.description = "Scene manager for loading Quake3 .bsp files.";
		mMetaData.sceneTypeMask = ST_INTERIOR;
		mMetaData.worldGeometrySupported = true;
	}
	//-----------------------------------------------------------------------
	SceneManager* BspSceneManagerFactory::createInstance(
		const String& instanceName)
	{
		return OGRE_NEW BspSceneManager(instanceName);
	}
	//-----------------------------------------------------------------------
	void BspSceneManagerFactory::destroyInstance(SceneManager* instance)
	{
		OGRE_DELETE instance;
	}

}

