A tangible 3D inventory for trunks and backpacks: rotate, stack and transfer items with volume, support and weight checks. Includes configurable profiles, a demo and integration tutorial.Validated on Windows with Unity 6000.3.5f1 using the Built-in Render Pipeline. The supplied Standard materials, transparency and grid shader are Built-in only; URP and HDRP are not supported in this release. No Asset Store package dependencies are required.Give inventory items a physical place in your game. Spatial Cargo packs rectangular item volumes into a 3D trunk or backpack, with 24 orientations, supported stacking and transfers that preserve the backpack contents.Configure item dimensions, weight, models and container sizes through ScriptableObjects. The inspection interface provides drag placement, rotation, layer selection, camera orbit and shell transparency. JSON saves retain a backup for recovery.Included: C# source, an interactive trunk-and-backpack demonstration, original procedural sample props, configuration assets and an illustrated setup and integration tutorial.Designed for single-player desktop mouse-and-keyboard games using the Built-in Render Pipeline. The example is a storage test rig, not a driveable car. A player controller, vehicle driving, multiplayer, irregular voxel shapes and URP/HDRP rendering are not included. Integrate your own controller through references and events.Unity 6000.3 LTS; validated on Windows with Unity 6000.3.5f1. Built-in Render Pipeline only.Rectangular 3D grid footprints, 24 orthogonal rotations, bounds and overlap checks.Optional full support for stacked items and configurable backpack weight limit.One trunk and one backpack per inventory instance; backpack contents survive equip/store operations.Runtime add-item API, open/close/change events and player-control suspension hooks.JSON persistence with a previous-save backup and validation on load.Mouse/keyboard IMGUI interface. Five sample item definitions and procedural visual prefabs.English tutorial: Assets/SpatialCargo/Documentation/Tutorial.html.Self-contained code and sample assets; no external runtime package dependency.OpenAI Codex assisted with C# implementation, refactoring, automated tests, procedural demo geometry and documentation. The sample props are generated with Unity primitives by the included editor script. No external AI-generated textures, photographs, voices or third-party character models are included. Validated in a clean Unity project and with the official Asset Store Tools validator.
