feat(sts-viewer): add item rotation support in inventory

Introduces the ability to rotate inventory items using the Alt button
during drag-and-drop.

- Updates `InventoryItemContainer` to handle rotation via
  `previewRotation`
- Adds `newRotation` parameter to `onMoveItem` callback and `moveItem`
  command
- Updates `InventoryItemState` to manage rotation state and compute
  transformed shapes
- Implements rotation logic in `renderGraphics` using `transformShape`

packages/sts-like-viewer/src/gameobjects/InventoryItemContainer.ts

@@ -10,9 +10,15 @@ import {
 } from "boardgame-core/samples/slay-the-spire-like";
 import { DisposableBag } from "../../../framework/dist";
 import { InventoryItemState } from "@/state/InventoryItemState";
+import { effect } from "@preact/signals-core";
 
 export interface InventoryItemContainerCallbacks {
-  onMoveItem: (itemId: string, newX: number, newY: number) => boolean;
+  onMoveItem: (
+    itemId: string,
+    newX: number,
+    newY: number,
+    newRotation: number,
+  ) => boolean;
 }
 
 export class InventoryItemContainer extends Phaser.GameObjects.Container {
@@ -44,21 +50,25 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
       label.setText(this.itemState.name.value);
     });
 
-    disposables.addEffect(() => {
+    disposables.add(
-      graphics.clear();
+      effect(() => {
-      if (!this.itemState.shape.value) return;
+        graphics.clear();
-      const cellRects = this.renderGraphics(
+        if (!this.itemState.shape.value) return;
-        graphics,
+        const cellRects = this.renderGraphics(
-        this.itemState.shape.value,
+          graphics,
-        this.itemState.color.value,
+          this.itemState.shape.value,
-      );
+          this.itemState.color.value,
+          this.itemState.previewRotation.value,
+        );
 
-      this.setupInteractive(cellRects);
+        return this.setupInteractive(cellRects);
-    });
+      }),
+    );
 
     disposables.addEffect(() => {
       if (!this.itemState.transform.value) return;
       this.snapBack(this.itemState.transform.value);
+      this.itemState.setPreviewRotation(0);
     });
   }
 
@@ -70,8 +80,15 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
     graphics: Phaser.GameObjects.Graphics,
     shape: ParsedShape,
     itemColor: number,
+    rotation: number,
   ): { x: number; y: number }[] {
-    const cells = transformShape(shape, IDENTITY_TRANSFORM);
+    const transform: Transform2D = {
+      offset: { x: 0, y: 0 },
+      rotation,
+      flipX: false,
+      flipY: false,
+    };
+    const cells = transformShape(shape, transform);
     const cellRects: { x: number; y: number }[] = [];
 
     for (const cell of cells) {
@@ -92,7 +109,7 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
     return cellRects;
   }
 
-  private setupInteractive(cellRects: { x: number; y: number }[]): void {
+  private setupInteractive(cellRects: { x: number; y: number }[]) {
     this.setScrollFactor(0);
     const cellSize = GRID_CONFIG.VIEWER_CELL_SIZE;
     this.setInteractive({
@@ -114,7 +131,8 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
 
     let startX = 0;
     let startY = 0;
-    dragDropEventEffect(this, (event) => {
+    return dragDropEventEffect(this, (event) => {
+      console.log(event.type);
       if (event.type === DragDropEventType.DOWN) {
         startX = this.x;
         startY = this.y;
@@ -122,18 +140,25 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
       } else if (event.type === DragDropEventType.MOVE) {
         this.x = startX + event.deltaX;
         this.y = startY + event.deltaY;
+      } else if (event.type === DragDropEventType.ALTBUTTON) {
+        const current = this.itemState.previewRotation.peek();
+        this.itemState.setPreviewRotation(current + 90);
       } else if (event.type === DragDropEventType.UP) {
         this.setAlpha(1);
-        if (!this.handleDragEnd()) {
+        const finalRotation = this.itemState.previewRotation.peek();
+        if (!this.handleDragEnd(finalRotation)) {
+          this.itemState.setPreviewRotation(0);
           const t = this.itemState.transform.peek();
           t && this.snapBack(t);
+        } else {
+          this.itemState.setPreviewRotation(0);
         }
         startX = startY = 0;
       }
     });
   }
 
-  private handleDragEnd(): boolean {
+  private handleDragEnd(finalRotation: number): boolean {
     const item = this.itemState.item;
     if (!item) return false;
 
@@ -151,9 +176,15 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
 
     if (
       clampedX !== item.transform.offset.x ||
-      clampedY !== item.transform.offset.y
+      clampedY !== item.transform.offset.y ||
+      finalRotation !== 0
     ) {
-      return this.callbacks.onMoveItem(item.id, clampedX, clampedY);
+      return this.callbacks.onMoveItem(
+        item.id,
+        clampedX,
+        clampedY,
+        finalRotation,
+      );
     }
     return false;
   }

packages/sts-like-viewer/src/gameobjects/InventoryItemSpawner.ts

@@ -42,8 +42,8 @@ export class InventoryItemSpawner implements Spawner<
       this.gridOffsetX,
       this.gridOffsetY,
       {
-        onMoveItem: (id, newX, newY) => {
+        onMoveItem: (id, newX, newY, newRotation) => {
-          return this.callbacks.onMoveItem(id, newX, newY);
+          return this.callbacks.onMoveItem(id, newX, newY, newRotation);
         },
       },
     );

packages/sts-like-viewer/src/scenes/InventoryTestScene.ts

@@ -93,8 +93,19 @@ export class InventoryTestScene extends ReactiveScene {
       this.gridOffsetX,
       this.gridOffsetY,
       {
-        onMoveItem: (itemId: string, newX: number, newY: number) => {
+        onMoveItem: (
-          return moveItem(this.inventorySignal, itemId, newX, newY);
+          itemId: string,
+          newX: number,
+          newY: number,
+          newRotation: number,
+        ) => {
+          return moveItem(
+            this.inventorySignal,
+            itemId,
+            newX,
+            newY,
+            newRotation,
+          );
         },
       },
     );

packages/sts-like-viewer/src/state/InventoryItemState.ts

@@ -1,44 +1,57 @@
-import { computed, signal, Signal } from "@preact/signals-core"
+import { computed, ReadonlySignal, signal, Signal } from "@preact/signals-core";
-import { ITEM_COLORS } from "@/config"
+import { ITEM_COLORS } from "@/config";
 import {
   type GameItem,
   type ParsedShape,
   type Transform2D,
-} from "boardgame-core/samples/slay-the-spire-like"
+} from "boardgame-core/samples/slay-the-spire-like";
 
 export class InventoryItemState {
-  private readonly _item: Signal<GameItem | undefined>
+  private readonly _item: Signal<GameItem | undefined>;
+  private readonly _previewRotation: Signal<number>;
 
-  readonly name: Signal<string>
+  readonly name: ReadonlySignal<string>;
-  readonly shape: Signal<ParsedShape | undefined>
+  readonly shape: ReadonlySignal<ParsedShape | undefined>;
-  readonly color: Signal<number>
+  readonly color: ReadonlySignal<number>;
-  readonly transform: Signal<Transform2D | undefined>
+  readonly transform: ReadonlySignal<Transform2D | undefined>;
+  readonly previewRotation: ReadonlySignal<number>;
 
   constructor(initialItem?: GameItem) {
-    this._item = signal(initialItem)
+    this._item = signal(initialItem);
+    this._previewRotation = signal(0);
 
     this.name = computed(() => {
-      const item = this._item.value
+      const item = this._item.value;
-      return item?.meta?.itemData.name ?? item?.id ?? ""
+      return item?.meta?.itemData.name ?? item?.id ?? "";
-    })
+    });
 
-    this.shape = computed(() => this._item.value?.shape)
+    this.shape = computed(() => this._item.value?.shape);
 
-    this.color = computed(() => this.computeColor(this._item.value?.id ?? ""))
+    this.color = computed(() => this.computeColor(this._item.value?.id ?? ""));
 
-    this.transform = computed(() => this._item.value?.transform)
+    this.transform = computed(() => this._item.value?.transform);
+
+    this.previewRotation = computed(() => {
+      const base = this._item.value?.transform?.rotation ?? 0;
+      return base + this._previewRotation.value;
+    });
   }
 
   get item(): GameItem | undefined {
-    return this._item.value
+    return this._item.value;
   }
 
   setItem(item: GameItem): void {
-    this._item.value = item
+    this._item.value = item;
+    this._previewRotation.value = 0;
+  }
+
+  setPreviewRotation(rotation: number): void {
+    this._previewRotation.value = rotation;
   }
 
   private computeColor(itemId: string): number {
-    const hash = itemId.split("").reduce((acc, c) => acc + c.charCodeAt(0), 0)
+    const hash = itemId.split("").reduce((acc, c) => acc + c.charCodeAt(0), 0);
-    return ITEM_COLORS[hash % ITEM_COLORS.length]
+    return ITEM_COLORS[hash % ITEM_COLORS.length];
   }
 }

packages/sts-like-viewer/src/state/inventory.ts

@@ -7,6 +7,7 @@ import {
   GameItemMeta,
   placeItem,
   removeItemFromGrid,
+  Transform2D,
   validatePlacement,
 } from "boardgame-core/samples/slay-the-spire-like";
 
@@ -36,6 +37,7 @@ export function moveItem(
   itemId: string,
   newX: number,
   newY: number,
+  newRotation?: number,
 ): boolean {
   const inventory = inventorySignal.value;
   const item = inventory.items.get(itemId);
@@ -44,9 +46,11 @@ export function moveItem(
     return false;
   }
 
-  const newTransform = {
+  const newTransform: Transform2D = {
-    ...item.transform,
     offset: { x: newX, y: newY },
+    rotation: newRotation === undefined ? item.transform.rotation : newRotation,
+    flipX: false,
+    flipY: false,
   };
 
   const removed = create(inventory, (inv) => {