weldverticesmodifier.cpp

// © Copyright 2010 - 2016 BlackTopp Studios Inc.
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*/
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/*
 -----------------------------------------------------------------------------
 This source file is part of ogre-procedural

 For the latest info, see http://code.google.com/p/ogre-procedural/

 Copyright (c) 2010-2013 Michael Broutin

 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
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 -----------------------------------------------------------------------------
 */
#ifndef _graphicsproceduralweldverticesmodifier_cpp
#define _graphicsproceduralweldverticesmodifier_cpp

#include "Graphics/Procedural/Mesh/weldverticesmodifier.h"

namespace Mezzanine
{
    namespace Graphics
    {
        namespace Procedural
        {
            WeldVerticesModifier::WeldVerticesModifier() :
                WeldTolerance(1e-3f)
                {  }

            WeldVerticesModifier::~WeldVerticesModifier()
                {  }

            ///////////////////////////////////////////////////////////////////////////////
            // Utility

            void WeldVerticesModifier::Modify(TriangleBuffer& Buffer)
            {
                std::map<Vector3, size_t, Vector3LengthCompare> MapExistingVertices;
                VertexContainer& Vertices = Buffer.GetVertices();
                IndexContainer& Indices = Buffer.GetIndices();

                size_t NewSize = Vertices.size();
                for( VertexIterator VertIt = Vertices.begin() ; VertIt != Vertices.end() ; ++VertIt )
                {
                    size_t CurrentIndex = VertIt - Vertices.begin();
                    if( CurrentIndex >= NewSize )
                        break;
                    if( MapExistingVertices.find(VertIt->Position) == MapExistingVertices.end() ) {
                        MapExistingVertices[VertIt->Position] = CurrentIndex;
                    }else{
                        size_t ExistingIndex = MapExistingVertices[VertIt->Position];
                        --NewSize;
                        if( CurrentIndex == NewSize ) {
                            for( IndexIterator IndexIt = Indices.begin() ; IndexIt != Indices.end() ; ++IndexIt )
                            {
                                if( (*IndexIt) == CurrentIndex ) {
                                    (*IndexIt) = ExistingIndex;
                                }
                            }
                        }else{
                            size_t LastIndex = NewSize;
                            (*VertIt) = Vertices[LastIndex];
                            for( IndexIterator IndexIt = Indices.begin() ; IndexIt != Indices.end() ; ++IndexIt )
                            {
                                if( (*IndexIt) == CurrentIndex ) {
                                    (*IndexIt) = ExistingIndex;
                                }else if( (*IndexIt) == LastIndex ) {
                                    (*IndexIt) = CurrentIndex;
                                }
                            }
                        }
                    }
                }
                Vertices.resize(NewSize);
            }

            String WeldVerticesModifier::GetName() const
                { return "WeldVerticesModifier"; }

            ///////////////////////////////////////////////////////////////////////////////
            // Configuration

            WeldVerticesModifier& WeldVerticesModifier::SetTolerance(const Real Tolerance)
            {
                this->WeldTolerance = Tolerance;
                return *this;
            }
        }//Procedural
    }//Graphics
}//Mezzanine

#endif