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(地基工)Ogre动画拾取函数优化版本

Posted on 2011-09-28 16:39 点点滴滴 阅读(535) 评论(0)  编辑 收藏 引用 所属分类: 08 游戏SDK
bool GraphicalWorld::pickPoint(const Ray& ray, Vector3 &hitpoint, const WS::StringVector& excludeobjects, Real max_distance/* = 9999.0f*/, uint32 mask /*= 0xFFFFFFFF*/)
{
    WS_ASSERT( msCore );

    
//const unsigned long mask = 0xFFFFFFFF;
    Ogre::Vector3 pOrigin = VEC_WS2OGRE(ray.getOrigin());
    Ogre::Vector3 pDirection 
= VEC_WS2OGRE(ray.getDirection());
    Ogre::Ray ogreRay(pOrigin, pDirection);
    
if (!mpRaySceneQuery)
    {
        mpRaySceneQuery 
= msCore->getSceneMgr()->createRayQuery( ogreRay, mask );
    }
    
else
    {
        mpRaySceneQuery
->setRay(ogreRay );    
        mpRaySceneQuery
->setQueryMask(mask);
    }        
    mpRaySceneQuery
->setSortByDistance(true);

    
if (mpRaySceneQuery->execute().size() <= 0return (false);

    
// at this point we have raycast to a series of different objects bounding boxes.
    
// we need to test these different objects to see which is the first polygon hit.
    
// there are some minor optimizations (distance based) that mean we wont have to
    
// check all of the objects most of the time, but the worst case scenario is that
    
// we need to test every triangle of every object.
    Ogre::Real closest_distance = max_distance;
    Ogre::Vector3 closest_result;
    Ogre::RaySceneQueryResult 
&query_result = mpRaySceneQuery->getLastResults();
    Ogre::MovableObject
* movable;

    
for (size_t qr_idx = 0; qr_idx < query_result.size(); qr_idx++)
    {
        
// stop checking if we have found a raycast hit that is closer
        
// than all remaining entities
        if ((closest_distance >= 0.0f&& (closest_distance < query_result[qr_idx].distance))
        {
            
break;
        }
        movable 
= query_result[qr_idx].movable;
        
// only check this result if its a hit against an entity
        if ((query_result[qr_idx].movable != NULL) && (query_result[qr_idx].movable->getMovableType().compare("Entity"== 0&& movable->isVisible())
        {
            Ogre::Entity
* pOgreEntity = static_cast<Ogre::Entity*>(movable);
            EntityMap::const_iterator itFind 
= mEntityMap.find(pOgreEntity);
            
if (itFind == mEntityMap.end())
                
continue;

            
// get the entity to check
            graphics::IEntity *pEntity = itFind->second;

            
const String& pname = pEntity->getPoolableObjectID();

            
bool foundinlist = false;
            
for(unsigned int lit = 0;lit < excludeobjects.size();lit++)
            {
                
if(excludeobjects[lit] == pname)
                {
                    foundinlist 
= true;
                    
break;
                }
            }

            
if(foundinlist) continue;

            
//parentOrientation * (parentScale * mPosition)
            std::pair<bool, Ogre::Real> hit = HitMesh(ogreRay, pOgreEntity);

            
// if it was a hit check if its the closest
            if (!hit.first) continue;

            
bool new_closest_found = false;
            
if ((closest_distance < 0.0f|| (hit.second< closest_distance))
            {
                
// this is the closest so far, save it off
                closest_distance = hit.second;
                new_closest_found 
= true;
            }

            
// if we found a new closest raycast for this object, update the
            
// closest_result before moving on to the next object.
            if (new_closest_found)
            {
                closest_result 
= ogreRay.getPoint(closest_distance);
            }
        }
    }

    
// return the result
    if (closest_distance != max_distance)
    {
        hitpoint 
= VEC_OGRE2WS(closest_result);
        
return true;
    }
    
else
    {
        
return false;
    }
}


拾取Mesh
std::pair<bool, Real> GraphicalWorld::HitMesh(const Ogre::Ray& ray,Ogre::Entity *entity)
{
    
//parentOrientation * (parentScale * mPosition)
    Ogre::Vector3 pPostion = entity->getParentNode()->_getDerivedPosition();
    Ogre::Vector3 pScale 
= entity->getParentNode()->_getDerivedScale();
    Ogre::Quaternion q 
= entity->getParentNode()->_getDerivedOrientation();

    Ogre::Ray localRay(q.Inverse() 
* (ray.getOrigin() - pPostion) / pScale,(q.Inverse() * ray.getDirection() / pScale).normalisedCopy());

    
bool added_shared = false;
    size_t current_offset 
= 0;
    size_t shared_offset 
= 0;
    size_t next_offset 
= 0;
    size_t index_offset 
= 0;

    std::pair
<bool, Ogre::Real> hit(false0);    
    Ogre::MeshPtr mesh 
= entity->getMesh();

    
bool useSoftwareBlendingVertices = entity->hasSkeleton();

    
if (useSoftwareBlendingVertices)
    {
        entity
->_updateAnimation();
    }
    added_shared 
= false;

    
// Run through the submeshes again, adding the data into the arrays
    for ( unsigned short i = 0; i < mesh->getNumSubMeshes(); ++i)
    {
        Ogre::SubMesh
* submesh = mesh->getSubMesh(i);
        
//----------------------------------------------------------------
        
// GET VERTEXDATA
        
//----------------------------------------------------------------
        Ogre::VertexData* vertex_data;

        
if(useSoftwareBlendingVertices)
            vertex_data 
= submesh->useSharedVertices ? entity->_getSkelAnimVertexData() : entity->getSubEntity(i)->_getSkelAnimVertexData();
        
else
            vertex_data 
= submesh->useSharedVertices ? mesh->sharedVertexData : submesh->vertexData;


        
if((!submesh->useSharedVertices)||(submesh->useSharedVertices && !added_shared))
        {
            
if(submesh->useSharedVertices)
            {
                added_shared 
= true;
            }
        }
        
//////////////////////////////////////////////////////////////////////////Vertex
        const Ogre::VertexElement* posElem =
            vertex_data
->vertexDeclaration->findElementBySemantic(Ogre::VES_POSITION);

        Ogre::HardwareVertexBufferSharedPtr vbuf 
=
            vertex_data
->vertexBufferBinding->getBuffer(posElem->getSource());

        unsigned 
char* vertex =
            static_cast
<unsigned char*>(vbuf->lock(Ogre::HardwareBuffer::HBL_READ_ONLY));
        
//////////////////////////////////////////////////////////////////////////Index
        Ogre::IndexData* index_data = submesh->indexData;
        size_t numTris 
= index_data->indexCount / 3;
        Ogre::HardwareIndexBufferSharedPtr ibuf 
= index_data->indexBuffer;
        
bool use32bitindexes = (ibuf->getType() == Ogre::HardwareIndexBuffer::IT_32BIT);
        unsigned 
long*  pLong = static_cast<unsigned long*>(ibuf->lock(Ogre::HardwareBuffer::HBL_READ_ONLY));
        unsigned 
short* pShort = reinterpret_cast<unsigned short*>(pLong);

        size_t offset 
= (submesh->useSharedVertices)? shared_offset : current_offset;
        size_t index_start 
= index_data->indexStart;
        size_t last_index 
= numTris * 3 + index_start;
        
float *pReal0, *pReal1, *pReal2;
        Ogre::Vector3 pVector30, pVector31,pVector32;

        
if (use32bitindexes)
        {
            
for (size_t k = index_start; k < last_index;)
            {                            
                posElem
->baseVertexPointerToElement(vertex + (pLong[k] + static_cast<unsigned long>( offset )) * vbuf->getVertexSize(), &pReal0);
                pVector30.x 
= pReal0[0];
                pVector30.y 
= pReal0[1];
                pVector30.z 
= pReal0[2];
                posElem
->baseVertexPointerToElement(vertex + (pLong[k + 1+ static_cast<unsigned long>( offset )) * vbuf->getVertexSize(), &pReal1);
                pVector31.x 
= pReal1[0];
                pVector31.y 
= pReal1[1];
                pVector31.z 
= pReal1[2];
                posElem
->baseVertexPointerToElement(vertex + (pLong[k + 2+ static_cast<unsigned long>( offset )) * vbuf->getVertexSize(), &pReal2);
                pVector32.x 
= pReal2[0];
                pVector32.y 
= pReal2[1];
                pVector32.z 
= pReal2[2];

                hit 
= Ogre::Math::intersects(localRay, pVector30,pVector31,pVector32, truefalse);
                
if (hit.first)
                {
                    
//parentOrientation * (parentScale * mPosition);
                    hit = Ogre::Math::intersects(ray, q *(pVector30 * pScale) + pPostion ,q *(pVector31 * pScale) + pPostion, q *(pVector32 * pScale) + pPostion, truefalse);
                    
if (hit.first) break;
                }
                
//
                k+=3;
            }                        
        }
        
else
        {
            
for (size_t k = index_start; k < last_index;)
            {
                posElem
->baseVertexPointerToElement(vertex + (static_cast<unsigned long>( pShort[k] ) + static_cast<unsigned long>( offset )) * vbuf->getVertexSize(), &pReal0);
                pVector30.x 
= pReal0[0];
                pVector30.y 
= pReal0[1];
                pVector30.z 
= pReal0[2];
                posElem
->baseVertexPointerToElement(vertex + (static_cast<unsigned long>( pShort[k + 1] ) + static_cast<unsigned long>( offset )) * vbuf->getVertexSize(), &pReal1);
                pVector31.x 
= pReal1[0];
                pVector31.y 
= pReal1[1];
                pVector31.z 
= pReal1[2];
                posElem
->baseVertexPointerToElement(vertex + (static_cast<unsigned long>( pShort[k + 2] ) + static_cast<unsigned long>( offset )) * vbuf->getVertexSize(), &pReal2);
                pVector32.x 
= pReal2[0];
                pVector32.y 
= pReal2[1];
                pVector32.z 
= pReal2[2];
                hit 
= Ogre::Math::intersects(localRay, pVector30,pVector31,pVector32, truefalse);
                
if (hit.first)
                {
                    hit 
= Ogre::Math::intersects(ray, q *(pVector30 * pScale) + pPostion ,q *(pVector31 * pScale) + pPostion, q *(pVector32 * pScale) + pPostion, truefalse);
                    
if (hit.first) break;
                }
                k
+=3;
            }
        }                    
        ibuf
->unlock();                
        vbuf
->unlock();
    }
    
return hit;
}