Function ChangeIds

Source/Engine/Serialization/JsonTools.cpp:11–73

#include "Engine/Utilities/Encryption.h"

void ChangeIds(rapidjson_flax::Value& obj, rapidjson_flax::Document& document, const Dictionary<Guid, Guid>& mapping)
{
    if (obj.IsObject())
    {
        for (rapidjson_flax::Value::MemberIterator i = obj.MemberBegin(); i != obj.MemberEnd(); ++i)
        {
            ChangeIds(i->value, document, mapping);
        }
    }
    else if (obj.IsArray())
    {
        for (rapidjson::SizeType i = 0; i < obj.Size(); i++)
        {
            ChangeIds(obj[i], document, mapping);
        }
    }
    else if (obj.IsString() && obj.GetStringLength() == 32)
    {
        auto value = JsonTools::GetGuid(obj);
        if (value.IsValid() && mapping.TryGet(value, value))
        {
            // Unoptimized version:
            //obj.SetString(value.ToString(Guid::FormatType::N).ToSTD().c_str(), 32, document.GetAllocator());

            // Optimized version:
            char buffer[32] =
            {
            // @formatter:off
                '0','0','0','0','0','0','0','0','0','0',
                '0','0','0','0','0','0','0','0','0','0',
                '0','0','0','0','0','0','0','0','0','0',
                '0','0'
            // @formatter:on
            };
            static const char* digits = "0123456789abcdef";
            uint32 n = value.A;
            char* p = buffer + 7;
            do
            {
                *p-- = digits[n & 0xf];
            } while ((n >>= 4) != 0);
            n = value.B;
            p = buffer + 15;
            do
            {
                *p-- = digits[n & 0xf];
            } while ((n >>= 4) != 0);
            n = value.C;
            p = buffer + 23;
            do
            {
                *p-- = digits[n & 0xf];
            } while ((n >>= 4) != 0);
            n = value.D;
            p = buffer + 31;
            do
            {
                *p-- = digits[n & 0xf];