ParticleBeamTrailVertexFactory.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
 
/*=============================================================================
    ParticleBeamTrailVertexFactory.h: Shared Particle Beam and Trail vertex 
                                        factory definitions.
=============================================================================*/
 
#pragma once
 
#include "CoreMinimal.h"
#include "UniformBuffer.h"
#include "VertexFactory.h"
#include "ParticleVertexFactory.h"
 
class FMaterial;
 
BEGIN_GLOBAL_SHADER_PARAMETER_STRUCT( FParticleBeamTrailUniformParameters, ENGINE_API)
    SHADER_PARAMETER( FVector4f, CameraRight )
    SHADER_PARAMETER( FVector4f, CameraUp )
    SHADER_PARAMETER( FVector4f, ScreenAlignment )
    SHADER_PARAMETER( uint32, bUseLocalSpace)
    SHADER_PARAMETER( FVector3f, LWCTile)
END_GLOBAL_SHADER_PARAMETER_STRUCT()
typedef TUniformBufferRef<FParticleBeamTrailUniformParameters> FParticleBeamTrailUniformBufferRef;
 
class FParticleBeamTrailVertexFactory : public FParticleVertexFactoryBase
{
    DECLARE_VERTEX_FACTORY_TYPE(FParticleBeamTrailVertexFactory);
 
public:
 
    FParticleBeamTrailVertexFactory( EParticleVertexFactoryType InType, ERHIFeatureLevel::Type InFeatureLevel )
        : FParticleVertexFactoryBase(InType, InFeatureLevel)
        , IndexBuffer(nullptr)
        , FirstIndex(0)
        , OutTriangleCount(0)
        , bUsesDynamicParameter(true)
    {}
 
    FParticleBeamTrailVertexFactory(ERHIFeatureLevel::Type InFeatureLevel)
        : FParticleVertexFactoryBase(PVFT_MAX, InFeatureLevel)
        , IndexBuffer(nullptr)
        , FirstIndex(0)
        , OutTriangleCount(0)
        , bUsesDynamicParameter(true)
    {}
 
    static ENGINE_API bool ShouldCompilePermutation(const FVertexFactoryShaderPermutationParameters& Parameters);
 
    static ENGINE_API void ModifyCompilationEnvironment(const FVertexFactoryShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment);
 
    static ENGINE_API void GetPSOPrecacheVertexFetchElements(EVertexInputStreamType VertexInputStreamType, FVertexDeclarationElementList& Elements);
    static ENGINE_API FRHIVertexDeclaration* GetPSOPrecacheVertexDeclaration(bool bUsesDynamicParameter);
 
    // FRenderResource interface.
    ENGINE_API virtual void InitRHI(FRHICommandListBase& RHICmdList) override;
 
    inline void SetBeamTrailUniformBuffer( FParticleBeamTrailUniformBufferRef InSpriteUniformBuffer )
    {
        BeamTrailUniformBuffer = InSpriteUniformBuffer;
    }
 
    inline FParticleBeamTrailUniformBufferRef GetBeamTrailUniformBuffer()
    {
        return BeamTrailUniformBuffer;
    }   
    
    ENGINE_API void SetVertexBuffer(const FVertexBuffer* InBuffer, uint32 StreamOffset, uint32 Stride);
 
    ENGINE_API void SetDynamicParameterBuffer(const FVertexBuffer* InDynamicParameterBuffer, uint32 StreamOffset, uint32 Stride);
    inline void SetUsesDynamicParameter(bool bInUsesDynamicParameter)
    {
        bUsesDynamicParameter = bInUsesDynamicParameter;
    }
 
    FIndexBuffer*& GetIndexBuffer()
    {
        return IndexBuffer;
    }
 
    uint32& GetFirstIndex()
    {
        return FirstIndex;
    }
 
    int32& GetOutTriangleCount()
    {
        return OutTriangleCount;
    }
 
private:
 
    FParticleBeamTrailUniformBufferRef BeamTrailUniformBuffer;
 
    FIndexBuffer* IndexBuffer;
    uint32 FirstIndex;
    int32 OutTriangleCount;
    bool bUsesDynamicParameter;
};