MeshConnectedComponents.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
 
// Port of geometry3sharp MeshConnectedComponents
 
#pragma once
 
#include "CoreMinimal.h"
#include "IntBoxTypes.h"
#include "DynamicMesh/DynamicMesh3.h"
#include "Containers/IndirectArray.h"
 
namespace UE
{
namespace Geometry
{
 
class FMeshConnectedComponents
{
public:
    const FDynamicMesh3* Mesh;
 
    struct FComponent
    {
        TArray<int> Indices;
    };
 
    TIndirectArray<FComponent> Components;
 
public:
 
    FMeshConnectedComponents(const FDynamicMesh3* MeshIn)
        : Mesh(MeshIn)
    {
    }
 
    //
    // Calculation functions. Call these to calculate different types of Components.
    //
 
    GEOMETRYCORE_API void FindConnectedTriangles(TFunction<bool(int32, int32)> TrisConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API void FindConnectedTriangles(const TArray<int>& TriangleROI, TFunction<bool(int32, int32)> TrisConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API void FindConnectedTriangles(TFunctionRef<bool(int)> IndexFilterFunc, TFunction<bool(int32, int32)> TrisConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API void FindTrianglesConnectedToSeeds(const TArray<int>& SeedTriangles, TFunction<bool(int32, int32)> TrisConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API bool InitializeFromTriangleComponents(const TArray<TArray<int32>>& ComponentLists, bool bValidateIDs);
 
    GEOMETRYCORE_API bool InitializeFromTriangleComponents(TArray<TArray<int32>>& ComponentLists, bool bMoveSubLists, bool bValidateIDs);
 
    GEOMETRYCORE_API void FindConnectedVertices(TFunction<bool(int32, int32)> VertsConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API void FindConnectedVertices(const TArray<int>& VertexROI, TFunction<bool(int32, int32)> VertsConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API void FindConnectedVertices(TFunctionRef<bool(int)> IndexFilterFunc, TFunction<bool(int32, int32)>VertsConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API void FindVerticesConnectedToSeeds(const TArray<int>& SeedVertices, TFunction<bool(int32, int32)> VertsConnectedPredicate = nullptr);
 
    GEOMETRYCORE_API bool InitializeFromVertexComponents(const TArray<TArray<int32>>& ComponentLists, bool bValidateIDs);
 
    GEOMETRYCORE_API bool InitializeFromVertexComponents(TArray<TArray<int32>>& ComponentLists, bool bMoveSubLists, bool bValidateIDs);
 
    //
    // Query functions. Only valid to call after a Calculation function has been called.
    //
 
    int32 Num() const
    {
        return Components.Num();
    }
 
    const FComponent& GetComponent(int32 Index) const { return Components[Index]; }
 
    FComponent& GetComponent(int32 Index) { return Components[Index]; }
 
    const FComponent& operator[](int32 Index) const { return Components[Index]; }
 
    FComponent& operator[](int32 Index) { return Components[Index]; }
 
    GEOMETRYCORE_API int32 GetLargestIndexByCount() const;
 
    GEOMETRYCORE_API void SortByCount(bool bLargestFirst = true);
 
 
 
public:
    auto begin() { return Components.begin(); }
    auto begin() const { return Components.begin(); }
    auto end() { return Components.end();  }
    auto end() const { return Components.end(); }
 
 
 
protected:
    //
    // Internal functions to calculate ROI
    //
    GEOMETRYCORE_API void FindTriComponents(FInterval1i ActiveRange, TArray<uint8>& ActiveSet, TFunction<bool(int32, int32)> TriConnectedPredicate);
    GEOMETRYCORE_API void FindTriComponents(const TArray<int32>& SeedList, TArray<uint8>& ActiveSet, TFunction<bool(int32, int32)> TriConnectedPredicate);
    GEOMETRYCORE_API void FindTriComponent(FComponent* Component, TArray<int32>& ComponentQueue, TArray<uint8>& ActiveSet);
    GEOMETRYCORE_API void FindTriComponent(FComponent* Component, TArray<int32>& ComponentQueue, TArray<uint8>& ActiveSet, TFunctionRef<bool(int32, int32)> TriConnectedPredicate);
    GEOMETRYCORE_API void RemoveFromActiveSet(const FComponent* Component, TArray<uint8>& ActiveSet);
 
    GEOMETRYCORE_API void FindVertComponents(FInterval1i ActiveRange, TArray<uint8>& ActiveSet, TFunction<bool(int32, int32)> VertsConnectedPredicate);
    GEOMETRYCORE_API void FindVertComponents(const TArray<int32>& SeedList, TArray<uint8>& ActiveSet, TFunction<bool(int32, int32)> VertsConnectedPredicate);
    GEOMETRYCORE_API void FindVertComponent(FComponent* Component, TArray<int32>& ComponentQueue, TArray<uint8>& ActiveSet);
    GEOMETRYCORE_API void FindVertComponent(FComponent* Component, TArray<int32>& ComponentQueue, TArray<uint8>& ActiveSet, TFunctionRef<bool(int32, int32)> VertsConnectedPredicate);
 
public:
    static GEOMETRYCORE_API void GrowToConnectedTriangles(const FDynamicMesh3* Mesh, 
        const TArray<int>& InputROI, 
        TArray<int>& ResultROI,
        TArray<int32>* QueueBuffer = nullptr, 
        TSet<int32>* DoneBuffer = nullptr,
        TFunctionRef<bool(int32, int32)> CanGrowPredicate = [](int32, int32) { return true; }
    );
 
 
    static GEOMETRYCORE_API void GrowToConnectedTriangles(const FDynamicMesh3* Mesh,
        const TArray<int>& InputROI,
        TSet<int>& ResultROI,
        TArray<int32>* QueueBuffer = nullptr,
        TFunctionRef<bool(int32, int32)> CanGrowPredicate = [](int32, int32) { return true; }
    );
 
 
    static GEOMETRYCORE_API void GrowToConnectedVertices(
        const FDynamicMesh3& Mesh,
        const TArray<int>& InputROI,
        TSet<int>& ResultROI,
        TArray<int32>* QueueBuffer = nullptr,
        TFunctionRef<bool(int32, int32)> CanGrowPredicate = [](int32, int32) { return true; }
    );
 
 
    static GEOMETRYCORE_API void GrowToConnectedEdges(
        const FDynamicMesh3& Mesh,
        const TArray<int>& InputROI,
        TSet<int>& ResultROI,
        TArray<int32>* QueueBuffer = nullptr,
        TFunctionRef<bool(int32, int32)> CanGrowPredicate = [](int32, int32) { return true; }
    );
 
 
};
 
 
} // end namespace UE::Geometry
} // end namespace UE