source: GTP/trunk/App/Demos/Vis/CHC_revisited/CHCTraverser.cpp @ 2755

#include "CHCTraverser.h"

namespace CHCDemo
{

CHCTraverser::CHCTraverser(): RenderTraverser() 
{
}


CHCTraverser::~CHCTraverser()
{
        //DelQueries();
}


void CHCTraverser::Render()
{
#if 0
        QueryQueue queryQueue;

        //-- PART 1: process finished occlusion queries
        while (!mDistanceQueue.empty() || !queryQueue.empty())
        {
                while (!queryQueue.empty() && 
                           (ResultAvailable(queryQueue.front()) || mDistanceQueue.empty()))
                {
                        HierarchyNode *node = queryQueue.front();
                        queryQueue.pop();
                        
                        // wait until result available
                        int visiblePixels = GetOcclusionQueryResult(node);

                        if(visiblePixels > mVisibilityThreshold)
                        {
                                PullUpVisibility(node);
                                TraverseNode(node);
                        }
                        else
                        {
                                mNumQueryCulledNodes ++;
                        }
                }       

                //-- PART 2: hierarchical traversal
                if (!mDistanceQueue.empty())
                {
                        HierarchyNode *node = mDistanceQueue.top();

                        mDistanceQueue.pop();
        
                        mNumTraversedNodes ++;

                        bool intersects;
                        
                        if (InsideViewFrustum(node, intersects))
                        {
                                // for near plane intersecting bounding box possible 
                                // wrong results => skip occlusion query
                                if(intersects)
                                {
                                        // update node's visited flag
                                        node->SetLastVisited(mFrameID);
                                        node->SetVisible(true);
                                        PullUpVisibility(node);
                                        TraverseNode(node);
                                }
                                else
                                {               
                                        // identify previously visible nodes
                                        bool wasVisible = node->Visible() && (node->LastVisited() == mFrameID - 1);
                                        
                                        // identify nodes that we cannot skip queries for
                                        bool leafOrWasInvisible = (node->LastVisited() != mFrameID) && (!wasVisible || node->IsLeaf());

                                        // reset node's visibility classification 
                                        node->SetVisible(false);

                                        // update node's visited flag
                                        node->SetLastVisited(mFrameID);
                                        
                                        // skip testing previously visible interior nodes
                                        if(leafOrWasInvisible)
                                        {
                                                IssueOcclusionQuery(node, wasVisible);
                                                queryQueue.push(node);
                                        }
                                        
                                        // always traverse a node if it was visible
                                        if(wasVisible)
                                                TraverseNode(node);
                                }
                        }
                        else
                        {
                                // for stats
                                mNumFrustumCulledNodes ++;
                        }
                }
        }
#endif
}

}