Filtering and Sorting

The filtering and sorting system allows controlling the display of items in an inventory without changing the data itself. Items remain in their places --- only how they are shown to the player changes.

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General Scheme

flowchart LR
    A["Inventory\n(all items)"] --> B["Filter\n(what to show)"]
    B --> C["Sort\n(in what order)"]
    C --> D["Display"]

Inventory data is not modified. Filtering and sorting only affect the visibility and order of slots in the UI.

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Filter Modes

When an item does not pass the filter, it can be handled in one of three ways:

Mode	What Happens
Hide	The slot is hidden (SetActive(false))
Dim	The slot remains visible but becomes inactive (dimmed, non-clickable)
MoveToEnd	The slot is moved to the end of the list and becomes inactive

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Built-in Filters

All filters are [Serializable] classes implementing ISlotFilter. They can be embedded via [SerializeReference] in any MonoBehaviour or ScriptableObject:

Filter	Description	Item Requirement
CategoryFilter	Show only items of a given category	IFilterable
RarityRangeFilter	Show items within a rarity range (min--max)	IFilterable
NameSearchFilter	Substring search by item name	---
CompositeFilter	Combines multiple filters with AND/OR logic	---

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Built-in Sorters

All sorters are [Serializable] classes implementing ISlotSorter:

Sorter	Sorts by	Item Requirement
NameSorter	DisplayName	---
CategorySorter	IFilterable.Category	IFilterable
RaritySorter	IFilterable.Rarity	IFilterable
SortValueSorter	ISortable.SortValue	ISortable
StackCountSorter	Stack count	---
CompositeSorter	Chain of sorters (first non-zero result wins)	---

All sorters support ascending and descending direction via the controller.

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Setup via Inspector

1. Add FilterSortController to the inventory GameObject.
2. Create filter/sorter assets:
   • Create > DragAndDrop > Filter > Slot Filter --- filter asset (SlotFilterSO). Choose the filter type via the [SerializeReference] picker.
   • Create > DragAndDrop > Filter > Slot Sorter --- sorter asset (SlotSorterSO).
   • Create > DragAndDrop > Filter > Filter Sort Preset --- combined preset (FilterSortPreset) with filter + sorter + display mode.
3. Add buttons:
   • FilterButton --- applies a SlotFilterSO on click.
   • SortButton --- applies a SlotSorterSO on click. Supports direction toggle.
   • FilterSortButton --- applies a combined FilterSortPreset on click.

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Code Examples

var controller = inventory.GetComponent<FilterSortController>();

// Use a [Serializable] filter instance
var filter = new CategoryFilter { Category = "Weapon" };
controller.SetFilter(filter);

// Sort with a [Serializable] sorter
controller.SetSorter(new RaritySorter(), ascending: false);

// Reset all
controller.ClearAll();

// Lambda filter (captures live values)
controller.SetFilter((in FilterContext ctx) =>
{
    if (ctx.Slot.Stack?.PrimaryAdapter is not IFilterable f) return false;
    return f.Rarity >= minRaritySlider.value;
});

// After changing fields on the active filter at runtime:
((CategoryFilter)controller.ActiveFilter).Category = "Armor";
controller.Refresh();

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Assets and Buttons

• SlotFilterSO --- ScriptableObject wrapping an ISlotFilter. Used by FilterButton.
• SlotSorterSO --- ScriptableObject wrapping an ISlotSorter. Used by SortButton.
• FilterSortPreset --- ScriptableObject combining filter + sorter + display mode + direction. Used by FilterSortButton.
• FilterButton --- UI button that applies/resets a SlotFilterSO. Supports toggle mode.
• SortButton --- UI button that applies/resets a SlotSorterSO. Supports toggle mode and direction toggle.
• FilterSortButton --- UI button that applies/resets a combined FilterSortPreset. Supports toggle mode and direction toggle.

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Class Reference

Class	Role
ISlotFilter	Core filter interface (Evaluate(in FilterContext))
ISlotSorter	Core sorter interface (Compare(in FilterContext, in FilterContext))
FilterContext	Context struct: Slot, Inventory, AllSlots, SlotIndex
FilterSortController	Controller: applies filter and sorting to an inventory
SlotFilterSO	ScriptableObject wrapper for shareable filter assets
SlotSorterSO	ScriptableObject wrapper for shareable sorter assets
FilterSortPreset	ScriptableObject: combined filter + sort preset
FilterButton	UI button for a single filter
SortButton	UI button for a single sorter
FilterSortButton	UI button for a combined preset
IFilterable	Item interface: Category, Subcategory, Rarity
ISortable	Item interface: SortValue, SortName