Use case: Inventory

This page outlines how developers can use the Unreal Engine zkEVM API module to display gamers' NFTs in the game's inventory

This can be useful for displaying the NFTs owned by a player in the game, or in your game's marketplace.

💡Who is this for?

Developers who want to use the zkEVM API in Unreal.

Overview

Displaying a player's inventory is a common feature in games that involve digital assets. To do this, you can simply send a request to the Immutable zkEVM API to fetch the NFTs owned by a player and then processing the request to display the NFTs in the game's inventory.

Displaying NFTs in the game inventory

To display a gamer NFT inventory, you can use the Search NFTs endpoint.

In order to obtain a list of NFTs owned by a player, you need to send a search request to the Immutable zkEVM API. The request parameters are populated based on the current state of the UI Marketplace policy settings.

Obtain NFTs owned by a player

    ImmutableOpenAPI::OpenAPIStacksApi::SearchNFTsRequest SearchNFTsRequest;
    
    SearchNFTsRequest.ChainName = Policy->GetChainName();
    SearchNFTsRequest.PageSize = (ListPanel->GetNumberOfColumns() * ListPanel->GetNumberOfRows());
    SearchNFTsRequest.PageCursor = PageCursor;
    SearchNFTsRequest.AccountAddress = GetOwningCustomLocalPLayer()->GetPassportWalletAddress();
    SearchNFTsRequest.ContractAddress = Policy->GetContracts();
    SearchNFTsRequest.OnlyIncludeOwnerListings = true;
    
    Policy->GetStacksAPI()->SearchNFTs(SearchNFTsRequest, ImmutableOpenAPI::OpenAPIStacksApi::FSearchNFTsDelegate::CreateUObject(this, &USearchNfTsWidget::OnSearchNFTsResponse));

Example of processing the response

    void USearchNfTsWidget::OnSearchNFTsResponse(const ImmutableOpenAPI::OpenAPIStacksApi::SearchNFTsResponse& Response)
    {
    
        ...
        int32 NumberOfResults = Response.Content.Result.Num();
        ...
        for (int32 ResultId = 0; ResultId < NumberOfResults; ResultId++)
        {
            
            ItemInterface->ProcessModel(ItemData);
            ItemWidget->RegisterOnSelectionChange(UItemWidget::FOnSelectionChange::CreateUObject(this, &USearchNfTsWidget::OnItemSelection));

            if (ItemData.Listings.Num())
            {
                ItemWidget->SetListForSellStatus(true);
            }
        }
    }

Example in-game inventory

You can view a full example of an in-game marketplace in the sample game here, which also utilises the Search NFTs endpoint.

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Related content

zkEVM APIs

Find out more information on what's available through the APIs and how to use them.

Learn more

Unreal SDK Reference

For more information on all the available methods in our Unreal SDK, check out the SDK Reference.

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Unreal Marketplace Tutorial

This tutorial series walks you through the in-game marketplace in our Unreal sample game.

Learn more