Generating a cubemap (or any texture) on the fly?

Development Rendering
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1

I have an algorithm which creates a cubemap using simplex noise. It creates 6 bitmaps in memory (not the file format just the raw data). How do I get unreal engine to load up the data into a cubemap at run time? Essentially im looking for an unreal engine equivalent to glTexImage2D() in opengl. I want to use the algorithm for procedurally generating things like planets.

2

Here is a way I have done it for a normal texture. I wrote all the FColor data to a TArray. Not the most efficent I am sure but maybe it will kick start you to the right path?

void TextureFromImage_Internal(const int32 SrcWidth, const int32 SrcHeight, const TArray<FColor> &SrcData, const bool UseAlpha, UTexture* &retVal)
    {
        // Create the texture
        retVal = UTexture2D::CreateTransient(
            SrcWidth,
            SrcHeight,
            PF_B8G8R8A8
        );
    
        // Lock the texture so it can be modified
        uint8* MipData = static_cast<uint8*>(((UTexture2D *)retVal)->PlatformData->Mips[0].BulkData.Lock(LOCK_READ_WRITE));
    
        // Create base mip.
        uint8* DestPtr = NULL;
        const FColor* SrcPtr = NULL;
        for (int32 y = 0; y<SrcHeight; y++)
        {
            DestPtr = &MipData[(SrcHeight - 1 - y) * SrcWidth * sizeof(FColor)];
            SrcPtr = const_cast<FColor*>(&SrcData[(SrcHeight - 1 - y) * SrcWidth]);
            for (int32 x = 0; x<SrcWidth; x++)
            {
                *DestPtr++ = SrcPtr->B;
                *DestPtr++ = SrcPtr->G;
                *DestPtr++ = SrcPtr->R;
                if (UseAlpha)
                {
                    *DestPtr++ = SrcPtr->A;
                }
                else
                {
                    *DestPtr++ = 0xFF;
                }
                SrcPtr++;
            }
        }
    
        // Unlock the texture
        ((UTexture2D*)retVal)->PlatformData->Mips[0].BulkData.Unlock();
        retVal->UpdateResource();
    }