LargeVolume.h

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/*******************************************************************************
Copyright (c) 2005-2009 David Williams

This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.

Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:

    1. The origin of this software must not be misrepresented; you must not
    claim that you wrote the original software. If you use this software
    in a product, an acknowledgment in the product documentation would be
    appreciated but is not required.

    2. Altered source versions must be plainly marked as such, and must not be
    misrepresented as being the original software.

    3. This notice may not be removed or altered from any source
    distribution.   
*******************************************************************************/

#ifndef __PolyVox_LargeVolume_H__
#define __PolyVox_LargeVolume_H__

#include "PolyVoxCore/BaseVolume.h"
#include "Impl/Block.h"
#include "PolyVoxCore/Log.h"
#include "PolyVoxCore/Region.h"
#include "PolyVoxCore/Vector.h"

#include <limits>
#include <cassert>
#include <cstdlib> //For abort()
#include <cstring> //For memcpy
#include <list>
#include <map>
#include <memory>
#include <stdexcept> //For invalid_argument
#include <vector>

namespace PolyVox
{
    template <typename VoxelType> class ConstVolumeProxy;

    template <typename VoxelType>
    class LargeVolume : public BaseVolume<VoxelType>
    {
    public:
        //There seems to be some descrepency between Visual Studio and GCC about how the following class should be declared.
        //There is a work around (see also See http://goo.gl/qu1wn) given below which appears to work on VS2010 and GCC, but
        //which seems to cause internal compiler errors on VS2008 when building with the /Gm 'Enable Minimal Rebuild' compiler
        //option. For now it seems best to 'fix' it with the preprocessor insstead, but maybe the workaround can be reinstated
        //in the future
        //typedef Volume<VoxelType> VolumeOfVoxelType; //Workaround for GCC/VS2010 differences.
        //class Sampler : public VolumeOfVoxelType::template Sampler< LargeVolume<VoxelType> >
#if defined(_MSC_VER)
        class Sampler : public BaseVolume<VoxelType>::Sampler< LargeVolume<VoxelType> > //This line works on VS2010
#else
                class Sampler : public BaseVolume<VoxelType>::template Sampler< LargeVolume<VoxelType> > //This line works on GCC
#endif
        {
        public:
            Sampler(LargeVolume<VoxelType>* volume);
            ~Sampler();

            Sampler& operator=(const Sampler& rhs);

            VoxelType getSubSampledVoxel(uint8_t uLevel) const;
            inline VoxelType getVoxel(void) const;          

            void setPosition(const Vector3DInt32& v3dNewPos);
            void setPosition(int32_t xPos, int32_t yPos, int32_t zPos);
            inline bool setVoxel(VoxelType tValue);

            void movePositiveX(void);
            void movePositiveY(void);
            void movePositiveZ(void);

            void moveNegativeX(void);
            void moveNegativeY(void);
            void moveNegativeZ(void);

            inline VoxelType peekVoxel1nx1ny1nz(void) const;
            inline VoxelType peekVoxel1nx1ny0pz(void) const;
            inline VoxelType peekVoxel1nx1ny1pz(void) const;
            inline VoxelType peekVoxel1nx0py1nz(void) const;
            inline VoxelType peekVoxel1nx0py0pz(void) const;
            inline VoxelType peekVoxel1nx0py1pz(void) const;
            inline VoxelType peekVoxel1nx1py1nz(void) const;
            inline VoxelType peekVoxel1nx1py0pz(void) const;
            inline VoxelType peekVoxel1nx1py1pz(void) const;

            inline VoxelType peekVoxel0px1ny1nz(void) const;
            inline VoxelType peekVoxel0px1ny0pz(void) const;
            inline VoxelType peekVoxel0px1ny1pz(void) const;
            inline VoxelType peekVoxel0px0py1nz(void) const;
            inline VoxelType peekVoxel0px0py0pz(void) const;
            inline VoxelType peekVoxel0px0py1pz(void) const;
            inline VoxelType peekVoxel0px1py1nz(void) const;
            inline VoxelType peekVoxel0px1py0pz(void) const;
            inline VoxelType peekVoxel0px1py1pz(void) const;

            inline VoxelType peekVoxel1px1ny1nz(void) const;
            inline VoxelType peekVoxel1px1ny0pz(void) const;
            inline VoxelType peekVoxel1px1ny1pz(void) const;
            inline VoxelType peekVoxel1px0py1nz(void) const;
            inline VoxelType peekVoxel1px0py0pz(void) const;
            inline VoxelType peekVoxel1px0py1pz(void) const;
            inline VoxelType peekVoxel1px1py1nz(void) const;
            inline VoxelType peekVoxel1px1py0pz(void) const;
            inline VoxelType peekVoxel1px1py1pz(void) const;

        private:
            //Other current position information
            VoxelType* mCurrentVoxel;
        };

        // Make the ConstVolumeProxy a friend
        friend class ConstVolumeProxy<VoxelType>;

        struct LoadedBlock
        {
        public:
            LoadedBlock(uint16_t uSideLength = 0)
                :block(uSideLength)
                ,timestamp(0)
            {
            }

            Block<VoxelType> block;
            uint32_t timestamp;
        };

    public:     
        LargeVolume
        (
            polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> dataRequiredHandler,
            polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> dataOverflowHandler,
            uint16_t uBlockSideLength = 32
        );
        LargeVolume
        (
            const Region& regValid,
            polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> dataRequiredHandler = 0,
            polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> dataOverflowHandler = 0,
            bool bPagingEnabled = false,
            uint16_t uBlockSideLength = 32
        );
        ~LargeVolume();

        VoxelType getBorderValue(void) const;
        VoxelType getVoxelAt(int32_t uXPos, int32_t uYPos, int32_t uZPos) const;
        VoxelType getVoxelAt(const Vector3DInt32& v3dPos) const;

        //Sets whether or not blocks are compressed in memory
        void setCompressionEnabled(bool bCompressionEnabled);
        void setMaxNumberOfUncompressedBlocks(uint32_t uMaxNumberOfUncompressedBlocks);
        void setMaxNumberOfBlocksInMemory(uint32_t uMaxNumberOfBlocksInMemory);
        void setBorderValue(const VoxelType& tBorder);
        bool setVoxelAt(int32_t uXPos, int32_t uYPos, int32_t uZPos, VoxelType tValue);
        bool setVoxelAt(const Vector3DInt32& v3dPos, VoxelType tValue);
        void prefetch(Region regPrefetch);
        void flush(Region regFlush);
        void flushAll();

        void clearBlockCache(void);
        float calculateCompressionRatio(void);
        uint32_t calculateSizeInBytes(void);

    protected:
        LargeVolume(const LargeVolume& rhs);

        LargeVolume& operator=(const LargeVolume& rhs);

    private:
        void initialise(const Region& regValidRegion, uint16_t uBlockSideLength);

        polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> m_funcDataRequiredHandler;
        polyvox_function<void(const ConstVolumeProxy<VoxelType>&, const Region&)> m_funcDataOverflowHandler;
    
        Block<VoxelType>* getUncompressedBlock(int32_t uBlockX, int32_t uBlockY, int32_t uBlockZ) const;
        void eraseBlock(typename std::map<Vector3DInt32, LoadedBlock >::iterator itBlock) const;
        bool setVoxelAtConst(int32_t uXPos, int32_t uYPos, int32_t uZPos, VoxelType tValue) const;

        //The block data
        mutable std::map<Vector3DInt32, LoadedBlock > m_pBlocks;

        //The cache of uncompressed blocks. The uncompressed block data and the timestamps are stored here rather
        //than in the Block class. This is so that in the future each VolumeIterator might to maintain its own cache
        //of blocks. However, this could mean the same block data is uncompressed and modified in more than one
        //location in memory... could be messy with threading.
        mutable std::vector< LoadedBlock* > m_vecUncompressedBlockCache;
        mutable uint32_t m_uTimestamper;
        mutable Vector3DInt32 m_v3dLastAccessedBlockPos;
        mutable Block<VoxelType>* m_pLastAccessedBlock;
        uint32_t m_uMaxNumberOfUncompressedBlocks;
        uint32_t m_uMaxNumberOfBlocksInMemory;

        //We don't store an actual Block for the border, just the uncompressed data. This is partly because the border
        //block does not have a position (so can't be passed to getUncompressedBlock()) and partly because there's a
        //good chance we'll often hit it anyway. It's a chunk of homogenous data (rather than a single value) so that
        //the VolumeIterator can do it's usual pointer arithmetic without needing to know it's gone outside the volume.
        VoxelType* m_pUncompressedBorderData;

        //The size of the volume
        Region m_regValidRegionInBlocks;

        //The size of the blocks
        uint16_t m_uBlockSideLength;
        uint8_t m_uBlockSideLengthPower;

        bool m_bCompressionEnabled;
        bool m_bPagingEnabled;
    };
}

#include "PolyVoxCore/LargeVolume.inl"
#include "PolyVoxCore/LargeVolumeSampler.inl"

#endif //__PolyVox_LargeVolume_H__