o3de/Gems/Atom/RHI/Code/Source/RHI.Reflect/SamplerState.cpp

/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */

#include <Atom/RHI.Reflect/SamplerState.h>
#include <AzCore/Preprocessor/Enum.h>
#include <AzCore/Preprocessor/EnumReflectUtils.h>
#include <AzCore/RTTI/BehaviorContext.h>
#include <AzCore/RTTI/TypeInfo.h>
#include <AzCore/Serialization/EditContext.h>
#include <AzCore/Serialization/SerializeContext.h>
#include <AzCore/Utils/TypeHash.h>

namespace AZ::RHI
{
    AZ_ENUM_DEFINE_REFLECT_UTILITIES(FilterMode);
    AZ_ENUM_DEFINE_REFLECT_UTILITIES(ReductionType);
    AZ_ENUM_DEFINE_REFLECT_UTILITIES(AddressMode);
    AZ_ENUM_DEFINE_REFLECT_UTILITIES(ComparisonFunc);
    AZ_ENUM_DEFINE_REFLECT_UTILITIES(BorderColor);

    void ReflectSamplerStateEnums(ReflectContext* context)
    {
        if (auto serializeContext = azrtti_cast<SerializeContext*>(context))
        {
            FilterModeReflect(*serializeContext);
            ReductionTypeReflect(*serializeContext);
            AddressModeReflect(*serializeContext);
            ComparisonFuncReflect(*serializeContext);
            BorderColorReflect(*serializeContext);
        }

        if (auto behaviorContext = azrtti_cast<BehaviorContext*>(context))
        {
            FilterModeReflect(*behaviorContext);
            ReductionTypeReflect(*behaviorContext);
            AddressModeReflect(*behaviorContext);
            ComparisonFuncReflect(*behaviorContext);
            BorderColorReflect(*behaviorContext);
        }
    }

    void SamplerState::Reflect(AZ::ReflectContext* context)
    {
        if (auto serializeContext = azrtti_cast<SerializeContext*>(context))
        {
            serializeContext->Class<SamplerState>()
                ->Version(3)
                ->Field("m_anisotropyMax", &SamplerState::m_anisotropyMax)
                ->Field("m_anisotropyEnable", &SamplerState::m_anisotropyEnable)
                ->Field("m_filterMin", &SamplerState::m_filterMin)
                ->Field("m_filterMag", &SamplerState::m_filterMag)
                ->Field("m_filterMip", &SamplerState::m_filterMip)
                ->Field("m_reductionType", &SamplerState::m_reductionType)
                ->Field("m_comparisonFunc", &SamplerState::m_comparisonFunc)
                ->Field("m_addressU", &SamplerState::m_addressU)
                ->Field("m_addressV", &SamplerState::m_addressV)
                ->Field("m_addressW", &SamplerState::m_addressW)
                ->Field("m_mipLodMin", &SamplerState::m_mipLodMin)
                ->Field("m_mipLodMax", &SamplerState::m_mipLodMax)
                ->Field("m_mipLodBias", &SamplerState::m_mipLodBias)
                ->Field("m_borderColor", &SamplerState::m_borderColor)
                ;

            if (auto editContext = serializeContext->GetEditContext())
            {
                editContext->Class<SamplerState>("SamplerState", "")
                    ->ClassElement(AZ::Edit::ClassElements::EditorData, "")
                    ->Attribute(AZ::Edit::Attributes::AutoExpand, false)
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_anisotropyMax, "Anisotropy Max", "Clamping value used if anisotropic filtering is enabled")
                        ->Attribute(AZ::Edit::Attributes::Min, 1)
                        ->Attribute(AZ::Edit::Attributes::Max, 16)
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_anisotropyEnable, "Anisotropy Enable", "Enable anisotropic filtering to reduce blur when sampling textures on surfaces at extreme angles")
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_filterMin, "Filter Min", "Minification filter used when sampling textures")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<FilterMode>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_filterMag, "Filter Mag", "Magnification filter used when sampling textures")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<FilterMode>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_filterMip, "Filter Mip", "Mipmap filter used when sampling textures")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<FilterMode>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_reductionType, "Reduction Type", "Specifies the type of filter reduction")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<ReductionType>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_comparisonFunc, "Comparison Func", "Function used to compare between texture samples")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<ComparisonFunc>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_addressU, "Address U", "Specifies the method for addressing U texture coordinates outside of the 0 to 1 range")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<AddressMode>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_addressV, "Address V", "Specifies the method for addressing V texture coordinates outside of the 0 to 1 range")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<AddressMode>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_addressW, "Address W", "Specifies the method for addressing W texture coordinates outside of the 0 to 1 range")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<AddressMode>())
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_mipLodMin, "Mip Lod Min", "Minimum mipmap level used for sampling textures")
                        ->Attribute(AZ::Edit::Attributes::Min, 0.0f)
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_mipLodMax, "Mip Lod Max", "Maximum mipmap level used for sampling textures")
                        ->Attribute(AZ::Edit::Attributes::Min, 0.0f)
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_mipLodBias, "Mip Lod Bias", "This value is added to the runtime selected mipmap level to adjust which mipmap is used for sampling textures")
                        ->Attribute(AZ::Edit::Attributes::Min, 0.0f)
                    ->DataElement(AZ::Edit::UIHandlers::Default, &SamplerState::m_borderColor, "Border Color", "Border color used at the edges of sampled textures")
                        ->Attribute(AZ::Edit::Attributes::EnumValues, AZ::Edit::GetEnumConstantsFromTraits<BorderColor>())
                    ;
            }
        }

        if (auto behaviorContext = azrtti_cast<AZ::BehaviorContext*>(context))
        {
            behaviorContext->Class<SamplerState>("SamplerState")
                ->Attribute(AZ::Script::Attributes::Scope, AZ::Script::Attributes::ScopeFlags::Automation)
                ->Attribute(AZ::Script::Attributes::Category, "RHI")
                ->Attribute(AZ::Script::Attributes::Module, "rhi")
                ->Constructor()
                ->Constructor<const SamplerState&>()
                ->Property("anisotropyMax", BehaviorValueProperty(&SamplerState::m_anisotropyMax))
                ->Property("anisotropyEnable", BehaviorValueProperty(&SamplerState::m_anisotropyEnable))
                ->Property("filterMin", BehaviorValueProperty(&SamplerState::m_filterMin))
                ->Property("filterMag", BehaviorValueProperty(&SamplerState::m_filterMag))
                ->Property("filterMip", BehaviorValueProperty(&SamplerState::m_filterMip))
                ->Property("reductionType", BehaviorValueProperty(&SamplerState::m_reductionType))
                ->Property("comparisonFunc", BehaviorValueProperty(&SamplerState::m_comparisonFunc))
                ->Property("addressU", BehaviorValueProperty(&SamplerState::m_addressU))
                ->Property("addressV", BehaviorValueProperty(&SamplerState::m_addressV))
                ->Property("addressW", BehaviorValueProperty(&SamplerState::m_addressW))
                ->Property("mipLodMin", BehaviorValueProperty(&SamplerState::m_mipLodMin))
                ->Property("mipLodMax", BehaviorValueProperty(&SamplerState::m_mipLodMax))
                ->Property("mipLodBias", BehaviorValueProperty(&SamplerState::m_mipLodBias))
                ->Property("borderColor", BehaviorValueProperty(&SamplerState::m_borderColor))
                ;
        }
    }

    SamplerState SamplerState::Create(
        FilterMode filterModeMinMag,
        FilterMode filterModeMip,
        AddressMode addressMode,
        BorderColor borderColor)
    {
        SamplerState descriptor;
        descriptor.m_filterMin = descriptor.m_filterMag = filterModeMinMag;
        descriptor.m_filterMip = filterModeMip;
        descriptor.m_addressU = descriptor.m_addressV = descriptor.m_addressW = addressMode;
        descriptor.m_borderColor = borderColor;
        return descriptor;
    }

    SamplerState SamplerState::CreateAnisotropic(
        uint32_t anisotropyMax,
        AddressMode addressMode)
    {
        SamplerState descriptor;
        descriptor.m_anisotropyEnable = 1;
        descriptor.m_anisotropyMax = anisotropyMax;
        descriptor.m_addressU = descriptor.m_addressV = descriptor.m_addressW = addressMode;
        return descriptor;
    }

    HashValue64 SamplerState::GetHash(HashValue64 seed /*= 0*/) const
    {
        return TypeHash64(*this, seed);
    }
}