source: trunk/VUT/GtpVisibilityPreprocessor/src/ViewCell.cpp @ 384

#include "ViewCell.h"
#include "Mesh.h"
#include "Intersectable.h"
#include "MeshKdTree.h"
#include "Triangle3.h"

ViewCell::HierarchyType ViewCell::sHierarchy = BSP;

ViewCell::ViewCell(): MeshInstance(NULL), mPiercingRays(0)
{
}

ViewCell::ViewCell(Mesh *mesh): MeshInstance(mesh), mPiercingRays(0)
{
}

ViewCell *ViewCell::Generate(Mesh *mesh)
{
        switch(sHierarchy)
        {
        case KD:
                return new ViewCell(mesh);
        case BSP:
                return new BspViewCell(mesh);
        default:
                Debug << "should not come here" << endl;
                return NULL;
        }
}

ViewCellPvs &ViewCell::GetPvs()
{
        return mPvs;
}

int ViewCell::Type() const 
{ 
        return VIEW_CELL; 
}

void ViewCell::DeriveViewCells(const ObjectContainer &objects, 
                                                           ViewCellContainer &viewCells, 
                                                           const int maxViewCells)
{
        // maximal max viewcells
        int limit = maxViewCells > 0 ? 
                Min((int)objects.size(), maxViewCells) : (int)objects.size();

        for (int i = 0; i < limit; ++ i)
        {
                Intersectable *object = objects[i];
                
                // extract the mesh instances
                if (object->Type() == Intersectable::MESH_INSTANCE)
                {
                        MeshInstance *inst = dynamic_cast<MeshInstance *>(object);

                        ViewCell *viewCell = Generate(inst->GetMesh());
                        viewCells.push_back(viewCell);
                }
                //TODO: transformed meshes
        }
}

ViewCell *ViewCell::ExtrudeViewCell(const Triangle3 &baseTri, const float height)
{
        // one mesh per view cell
        Mesh *mesh = new Mesh();
        
        //-- construct prism

        // bottom 
        mesh->mFaces.push_back(new Face(2,1,0));
        // top
    mesh->mFaces.push_back(new Face(3,4,5));
        // sides
        mesh->mFaces.push_back(new Face(1, 4, 3, 0));
        mesh->mFaces.push_back(new Face(2, 5, 4, 1));
        mesh->mFaces.push_back(new Face(3, 5, 2, 0));

        //--- extrude new vertices for top of prism
        Vector3 triNorm = baseTri.GetNormal();

        Triangle3 topTri;       

        // add base vertices and calculate top vertices
        for (int i = 0; i < 3; ++ i)
                mesh->mVertices.push_back(baseTri.mVertices[i]);
        
        // add top vertices     
        for (int i = 0; i < 3; ++ i)
                mesh->mVertices.push_back(baseTri.mVertices[i] + height * triNorm);
        
        mesh->Preprocess();

        return Generate(mesh);
}

ViewCell *ViewCell::Merge(ViewCell &front, ViewCell &back)
{
        ViewCell *vc = Generate();
        // merge pvs
        vc->mPvs.Merge(front.mPvs, back.mPvs);

        // merge ray sets
        stable_sort(front.mPiercingRays.begin(), front.mPiercingRays.end());
        stable_sort(back.mPiercingRays.begin(), back.mPiercingRays.end());

        std::merge(front.mPiercingRays.begin(), front.mPiercingRays.end(),
                           back.mPiercingRays.begin(), back.mPiercingRays.end(), 
                           vc->mPiercingRays.begin());

        return vc;
}

void ViewCell::AddPassingRay(const Ray &ray, const int contributions)
{
        mPassingRays.AddRay(ray, contributions);
}