CollisionContext.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
 
#include "Chaos/ChaosDebugName.h"
#include "Chaos/Core.h"
 
namespace Chaos
{
    namespace Private
    {
        class FCollisionContextAllocator;
    }
 
    class FParticlePairMidPhase;
 
    class FCollisionDetectorSettings
    {
    public:
        FCollisionDetectorSettings()
            : BoundsExpansion(0)
            , BoundsVelocityInflation(0)
            , MaxVelocityBoundsExpansion(0)
            , BoundsVelocityInflationMACD(0)
            , MaxVelocityBoundsExpansionMACD(0)
            , bFilteringEnabled(true)
            , bDeferNarrowPhase(false)
            , bAllowManifolds(true)
            , bAllowManifoldReuse(true)
            , bAllowCCD(true)
            , bAllowMACD(false)
            , EvolutionName()
        {
        }
 
        // Shape bounds are expanded by this in all 3 directions. This is also used as the CullDistance for collision response.
        FReal BoundsExpansion;
        
        // Shape bounds in the broadphase are expanded by this multiple of velocity (normal collision mode)
        FReal BoundsVelocityInflation;
 
        // We only allow the bounds to grow from velocity by this much (normal collision mode)
        FReal MaxVelocityBoundsExpansion;
 
        // Shape bounds in the broadphase are expanded by this multiple of velocity (movement-aware collision mode)
        FReal BoundsVelocityInflationMACD;
 
        // We only allow the bounds to grow from velocity by this much (movement-aware collision mode)
        FReal MaxVelocityBoundsExpansionMACD;
 
        // Whether to check the shape query flags in the narrow phase (e.g., Rigid Body nodes have already performed filtering prior to collision detection)
        bool bFilteringEnabled;
 
        // Whether to defer the narrow phase to the constraint-solve phase. This is only enabled by RBAN. It is not useful for the main solver because 
        // we would not know the contact details when we call the collision modifier callbacks. It is used by RBAN to allow us to run 1 joint iteration 
        // prior to collision detection which gives better results.
        bool bDeferNarrowPhase;
 
        // Whether to use one-shot manifolds where supported
        bool bAllowManifolds;
 
        // Whether we can reuse manifolds between frames if contacts have not moved far
        bool bAllowManifoldReuse;
 
        // Whether CCD is allowed (disabled for RBAN)
        bool bAllowCCD;
 
        // Whether MACD is allowed (disabled for RBAN)
        bool bAllowMACD;
 
        // Useful for debugging (esp. PIE client/server)
        FSharedDebugName EvolutionName;
 
        const FString& GetName() const
        {
            return EvolutionName.Value();
        }
    };
 
    class FCollisionContext
    {
    public:
        FCollisionContext()
            : Settings(nullptr)
            , Allocator(nullptr)
            , MidPhase(nullptr)
        {
        }
 
        void Reset()
        {
            Settings = nullptr;
            Allocator = nullptr;
            MidPhase = nullptr;
        }
 
        const FCollisionDetectorSettings& GetSettings() const { return *Settings; }
        void SetSettings(const FCollisionDetectorSettings& InSettings) { Settings = &InSettings; }
 
        Private::FCollisionContextAllocator* GetAllocator() const { return Allocator; }
        void SetAllocator(Private::FCollisionContextAllocator* InAllocator) { Allocator = InAllocator; }
 
        const FCollisionDetectorSettings* Settings;
 
        Private::FCollisionContextAllocator* Allocator;
 
        // This is used in the older collision detection path which is still used for particles that do not flatten their implicit hierrarchies
        // into the Particle's ShapesArray. Currently this is only Clusters.
        // @todo(chaos): remove thsi from here and make it a parameter on ConstructCollisions and all inner functions.
        FParticlePairMidPhase* MidPhase;
    };
}