/*
 * -----------------------------------------------------------------------------
 * This source file is part of OGRE
 * (Object-oriented Graphics Rendering Engine)
 * For the latest info, see http://www.ogre3d.org/
 *
 * Copyright (c) 2000-2014 Torus Knot Software Ltd
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 * -----------------------------------------------------------------------------
 */
#include "OgreLodData.h"

namespace Ogre
{
// Use float limits instead of Real limits, because LodConfigSerializer may convert them to float.
    const Real LodData::NEVER_COLLAPSE_COST = std::numeric_limits<float>::max();
    const Real LodData::UNINITIALIZED_COLLAPSE_COST = std::numeric_limits<float>::infinity();

    void LodData::Vertex::addEdge( const LodData::Edge& edge )
    {
        OgreAssert(edge.dst != this, "");
        VEdges::iterator it;
        it = edges.add(edge);
        if (it == edges.end())
        {
            edges.back().refCount = 1;
        }
        else
        {
            it->refCount++;
        }
    }

    void LodData::Vertex::removeEdge( const LodData::Edge& edge )
    {
        VEdges::iterator it = edges.findExists(edge);
        if (it->refCount == 1)
        {
            edges.remove(it);
        }
        else
        {
            it->refCount--;
        }
    }

    bool LodData::VertexEqual::operator() (const LodData::Vertex* lhs, const LodData::Vertex* rhs) const
    {
        return lhs->position == rhs->position;
    }

    size_t LodData::VertexHash::operator() (const LodData::Vertex* v) const
    {
        // Stretch the values to an integer grid.
        Real stretch = (Real)0x7fffffff / mGen->mMeshBoundingSphereRadius;
        int hash = (int)(v->position.x * stretch);
        hash ^= (int)(v->position.y * stretch) * 0x100;
        hash ^= (int)(v->position.z * stretch) * 0x10000;
        return (size_t)hash;
    }

    void LodData::Triangle::computeNormal()
    {
        // Cross-product 2 edges
        Vector3 e1 = vertex[1]->position - vertex[0]->position;
        Vector3 e2 = vertex[2]->position - vertex[1]->position;

        normal = e1.crossProduct(e2);
        normal.normalise();
    }

    bool LodData::Triangle::hasVertex(const LodData::Vertex* v) const
    {
        return (v == vertex[0] || v == vertex[1] || v == vertex[2]);
    }

    unsigned int LodData::Triangle::getVertexID(const LodData::Vertex* v) const
    {
        for (int i = 0; i < 3; i++)
        {
            if (vertex[i] == v)
            {
                return vertexID[i];
            }
        }
        OgreAssert(0, "");
        return 0;
    }
    bool LodData::Triangle::isMalformed()
    {
        return vertex[0] == vertex[1] || vertex[0] == vertex[2] || vertex[1] == vertex[2];
    }

    LodData::Edge::Edge(LodData::Vertex* destination) :
        dst(destination)
#if OGRE_DEBUG_MODE
        , collapseCost(UNINITIALIZED_COLLAPSE_COST)
#endif
        , refCount(0)
    {

    }

    LodData::Edge::Edge(const LodData::Edge& b)
    {
        *this = b;
    }

    bool LodData::Edge::operator< (const LodData::Edge& other) const
    {
        return (size_t) dst < (size_t) other.dst;   // Comparing pointers for uniqueness.
    }

    LodData::Edge& LodData::Edge::operator= (const LodData::Edge& b)
    {
        dst = b.dst;
        collapseCost = b.collapseCost;
        refCount = b.refCount;
        return *this;
    }

    bool LodData::Edge::operator== (const LodData::Edge& other) const
    {
        return dst == other.dst;
    }

}