SegmentMesh.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
 
#include "Chaos/Core.h"
#include "Chaos/Array.h"
#include "Chaos/Map.h"
#include "Chaos/Vector.h"
 
namespace Chaos
{
    template<class T, int d>
    class TParticles;
 
    class FSegmentMesh
    {
    public:
        FSegmentMesh()
        {}
        CHAOS_API FSegmentMesh(TArray<TVec2<int32>>&& Elements);
        FSegmentMesh(const FSegmentMesh& Other) = delete;
        FSegmentMesh(FSegmentMesh&& Other)
            : MElements(MoveTemp(Other.MElements))
            , MPointToEdgeMap(MoveTemp(Other.MPointToEdgeMap))
            , MPointToNeighborsMap(MoveTemp(Other.MPointToNeighborsMap))
        {}
        CHAOS_API ~FSegmentMesh();
 
        CHAOS_API void Init(const TArray<TVec2<int32>>& Elements);
        CHAOS_API void Init(TArray<TVec2<int32>>&& Elements);
 
        int32 GetNumElements() const
        {
            return MElements.Num();
        }
 
        const TArray<TVec2<int32>>& GetElements() const
        {
            return MElements;
        }
 
        const TSet<int32>* GetNeighbors(const int32 index) const
        {
            return GetPointToNeighborsMap().Find(index);
        }
 
        CHAOS_API const TMap<int32, TSet<int32>>& GetPointToNeighborsMap() const;
 
        CHAOS_API const TMap<int32, TArray<int32>>& GetPointToEdges() const;
 
        CHAOS_API TArray<FReal> GetEdgeLengths(
            const TParticles<FReal, 3>& InParticles, 
            const bool lengthSquared = false) const;
 
    private:
        CHAOS_API void _ClearAuxStructures();
 
        CHAOS_API void _UpdatePointToNeighborsMap() const;
 
        CHAOS_API void _UpdatePointToEdgesMap() const;
 
    private:
        // We use TVector rather than FEdge to represent connectivity because
        // sizeof(TVec2<int32>) < sizeof(FEdge).  FEdge has an extra int32
        // member called Count, which we don't currently have a use for.
        TArray<TVec2<int32>> MElements;
 
        // Members are mutable so they can be generated on demand by const API.
        mutable TMap<int32, TArray<int32>> MPointToEdgeMap;
        mutable TMap<int32, TSet<int32>> MPointToNeighborsMap;
    };
 
    template <typename T>
    using TSegmentMesh = FSegmentMesh;
 
} // namespace Chaos