source: GTP/trunk/Lib/Vis/OnlineCullingCHC/src/RandomUpdateCullingManager.cpp @ 2538

#include "RandomUpdateCullingManager.h"
#include <time.h>
#include "CullingLogManager.h"
#include <vector>
//#include <iostream>
#include <sstream>


using namespace std;


namespace GtpVisibility {

const static int R_CANDIDATES = 1;

//-----------------------------------------------------------------------
RandomUpdateCullingManager::RandomUpdateCullingManager(): mRandomCandidates(R_CANDIDATES)
{
}
//-----------------------------------------------------------------------
RandomUpdateCullingManager::RandomUpdateCullingManager(const unsigned int randomCandidates)
{       
        mRandomCandidates = std::max(randomCandidates, (unsigned int)1);
}
//-----------------------------------------------------------------------
void RandomUpdateCullingManager::SetRandomCandidates(const unsigned int randomCandidates)
{
        mRandomCandidates = std::max(randomCandidates, (unsigned int)1);
}
//-----------------------------------------------------------------------
void RandomUpdateCullingManager::RenderScene()
{
        if (0) CullingLogManager::GetSingleton()->LogMessage("ruc");

        QueryQueue queryQueue;
        unsigned int visiblePixels = 0;
        
        /////////////
        //-- PART 1: process finished occlusion queries

        while (!mHierarchyInterface->GetQueue()->empty() || !queryQueue.empty())
        {
                bool resultAvailable = false;

                //-- only wait for result if there are no nodes to process
                while (!queryQueue.empty() && 
                                queryQueue.front().second->GetQueryResult(visiblePixels, 
                                mHierarchyInterface->GetQueue()->empty()))
                {
                HierarchyNode *node = queryQueue.front().first;
                        
                        queryQueue.pop();
                        
                        if (visiblePixels > mVisibilityThreshold)
                        {
                                // in case geometry is in interior node: 
                                // ensure that we only traverse once
                                if (!mHierarchyInterface->IsNodeVisible(node) &&
                                        !mHierarchyInterface->IsNodeFullyVisible(node))
                                {
                                        mHierarchyInterface->TraverseNode(node);
                                }

                                mHierarchyInterface->PullUpVisibility(node);
                        }
                        else
                        {       
                                mHierarchyInterface->SetNodeVisible(node, false);

                                ++ mNumQueryCulledNodes;
                                
                                if (mVisualizeCulledNodes)
                                {
                                        mHierarchyInterface->VisualizeCulledNode(node, QUERY_CULLED);
                                }
                        }
                }
                
                //-- PART 2: hierarchical traversal
                if (!mHierarchyInterface->GetQueue()->empty())
                {
                        HierarchyNode *node = mHierarchyInterface->GetQueue()->top();
                        mHierarchyInterface->GetQueue()->pop();
                                
                        bool intersects = false;

                        if (!mHierarchyInterface->CheckFrustumVisible(node, intersects))
                        {
                                ++ mNumFrustumCulledNodes;

                                if (mVisualizeCulledNodes)
                                {
                                        mHierarchyInterface->VisualizeCulledNode(node, FRUSTUM_CULLED);
                                }
                        }
                        //-- if node intersects near plane, skip query because wrong results possible
                        else if (intersects)
                        {
                                SkipQuery(node);
                        }
                        else
                        {
                                // fully visible subtree => render all in one batch
                                if (mHierarchyInterface->IsNodeFullyVisible(node))
                                {
                                        int nodesTested = 0;

                                        // use different algorithm to find random candidates
#if 1
                                        HierarchyNodeContainer mynodes;
                                        mHierarchyInterface->CollectLeaves(node, mynodes);

                                        const int p = mRandomCandidates * RAND_MAX / (int)mynodes.size();

                                        HierarchyNodeContainer::const_iterator nit, nit_end = mynodes.end();

                                        for (nit = mynodes.begin(); nit != nit_end; ++ nit)
                                        {
                                                HierarchyNode *leaf = *nit;

                                                if (rand() > p)
                                                        continue;

                                                bool intersects = false;
                                                const bool frustumCulled = !mHierarchyInterface->CheckFrustumVisible(leaf, intersects);

                                                // don't test in these cases ...
                                                if (frustumCulled || intersects)
                                                        continue;
                
                                                ++ nodesTested;
                                                
                                                mHierarchyInterface->SetNodeVisible(leaf, false);

                                                // update node's visited flag: this is important as we are not testing
                                                // all nodes in the hierarchy in this mode
                                                mHierarchyInterface->PullUpLastVisited(leaf, mHierarchyInterface->GetFrameId());
                                                // issue the query
                                                mHierarchyInterface->IssueNodeOcclusionQuery(node, mTestGeometryForVisibleLeaves);
                                        }

                                        //std::stringstream d; d << "rc: " << mRandomCandidates << " tested: " << nodesTested << " of " << (int)mynodes.size();
                                        //CullingLogManager::GetSingleton()->LogMessage(d.str());

#else
                                        
                                        HierarchyNode *leaf = mHierarchyInterface->GetRandomLeaf(node);
                                        
                                        bool intersects = false;
                                        const bool frustumCulled = !mHierarchyInterface->CheckFrustumVisible(leaf, intersects);

                                        if (frustumCulled || intersects) // don't test in these cases ...
                                                continue;

                                        ++ nodesTested;

                                        mHierarchyInterface->SetNodeVisible(leaf, false);

                                        // update node's visited flag: this is important as we are not testing
                                        // all nodes in the hierarchy in this mode
                                        mHierarchyInterface->PullUpLastVisited(leaf, mHierarchyInterface->GetFrameId());
                                        // issue the query
                                        mHierarchyInterface->IssueNodeOcclusionQuery(leaf, mTestGeometryForVisibleLeaves);

#endif
                                        
                                        mHierarchyInterface->RenderNodeRecursive(node);

                                        // bail out here, recursion has finished
                                        continue;
                                }

                                // identify previously visible nodes
                                const bool wasVisible = mHierarchyInterface->IsNodeVisible(node) && 
                                        (mHierarchyInterface->LastVisited(node) == mHierarchyInterface->GetFrameId() - 1);
                                        
                                // if we assume node to be visible in this frame => skip query 
                                const bool skipQuery = false;
                                //wasVisible && mHierarchyInterface->HasGeometry(node);

                                if (skipQuery)
                                {
                                        SkipQuery(node);
                                        continue;
                                }
                                                        
                // identify nodes that we cannot skip queries for
                                // geometry not only in leaves => test for renderable geometry
                                const bool issueQuery = !wasVisible || mHierarchyInterface->HasGeometry(node);
                                                        
                                // reset node's visibility classification
                                // set visible if geometry in node => we only traverse the node once
                                mHierarchyInterface->SetNodeVisible(node, wasVisible && issueQuery);

                                // update node's visited flag
                                mHierarchyInterface->SetLastVisited(node, mHierarchyInterface->GetFrameId());
                                

                                // skip testing previously visible nodes without geometry
                                if (issueQuery)
                                {
                                        ++ mNumQueriesIssued;
                                        
                                        const bool testGeometry = wasVisible && mHierarchyInterface->IsLeaf(node) && mTestGeometryForVisibleLeaves;

                                        queryQueue.push(QueryPair(node, mHierarchyInterface->
                                                IssueNodeOcclusionQuery(node, testGeometry)));
                                }
                                
                                // always traverse a node if it was visible
                                if (wasVisible)
                                {
                                        mHierarchyInterface->TraverseNode(node);
                                }
                        }
                }
        }

        // update the fully visible classifications
        mHierarchyInterface->DetermineFullVisibility(mHierarchyInterface->GetHierarchyRoot());
}
//-----------------------------------------------------------------------
inline void RandomUpdateCullingManager::SkipQuery(HierarchyNode *node) const
{
        // -- set node to be visible in this frame, then traverse it
        mHierarchyInterface->SetLastVisited(node, mHierarchyInterface->GetFrameId());
        
        mHierarchyInterface->PullUpVisibility(node);                    
        mHierarchyInterface->TraverseNode(node);
}
//-----------------------------------------------------------------------
void RandomUpdateCullingManager::SetTestGeometryForVisibleLeaves(const bool testGeometry)
{
        mTestGeometryForVisibleLeaves = testGeometry;
}
//-----------------------------------------------------------------------
bool RandomUpdateCullingManager::GetTestGeometryForVisibleLeaves()
{
        return mTestGeometryForVisibleLeaves;
}

} // namespace GtpVisibility