UE4笔记-Collision与Trace相关

碰撞和射线追踪相关笔记，备查

 

 

Q.ECollisionChannel/ETraceTypeQuery/EObjectTypeQuery相互转换：

UEngineTypes::ConvertToObjectType();
UEngineTypes::ConvertToCollisionChannel();
UEngineTypes::ConvertToTraceType();

 

 

Q.高精度的射线捕获(使用UE::Geometry::*)对UE::Geometry::FDynamicMesh3进行射线捕获

//
UE::Geometry::FDynamicMesh3 SourceMesh;
UE::Geometry::FDynamicMeshAABBTree3 MeshAABBTree;
bool *::RayHit(
    FVector RayOrigin, FVector RayDirection, FVector& WorldHitPoint, float& HitDistance,
    int& NearestTriangle, FVector& TriBaryCoords, float MaxDistance)
{
    FTransform3d ActorToWorld(GetActorTransform());
    FVector3d WorldDirection(RayDirection);
    WorldDirection.Normalize();
    FRay3d LocalRay(
        ActorToWorld.InverseTransformPosition(static_cast<FVector3d>(RayOrigin)),
        ActorToWorld.InverseTransformVector(WorldDirection));
    UE::Geometry::IMeshSpatial::FQueryOptions QueryOptions;
    if (MaxDistance > 0)
    {
        QueryOptions.MaxDistance = MaxDistance;
    }
    NearestTriangle = MeshAABBTree.FindNearestHitTriangle(LocalRay, QueryOptions);
    if (SourceMesh.IsTriangle(NearestTriangle))
    {
        UE::Geometry::FIntrRay3Triangle3d InterQuery = UE::Geometry::TMeshQueries<FDynamicMesh3>::TriangleIntersection(
            SourceMesh, NearestTriangle, LocalRay);
        if (InterQuery.IntersectionType == EIntersectionType::Point)
        {
            HitDistance = InterQuery.RayParameter;
            WorldHitPoint = static_cast<FVector>(ActorToWorld.TransformPosition(
                LocalRay.PointAt(InterQuery.RayParameter)));
            TriBaryCoords = static_cast<FVector>(InterQuery.TriangleBaryCoords);
            return true;
        }
    }
    return false;