feat: SceneManager creates pdf-page items with culling support

frontend/src/canvas/PixiCanvas.tsx

@@ -22,6 +22,7 @@ import { TextureManager } from './TextureManager';
 import { ImageSprite } from './sprites/ImageSprite';
 import { VideoSprite } from './sprites/VideoSprite';
 import { AnimatedGifSprite } from './sprites/AnimatedGifSprite';
+import { PdfPageSprite } from './sprites/PdfPageSprite';
 import { SpringManager } from './spring';
 import { convertFabricToV2 } from './scene-format';
 import type { SceneData } from './scene-format';
@@ -197,7 +198,7 @@ const PixiCanvas = forwardRef<PixiCanvasHandle, PixiCanvasProps>(
           const vcx = bounds.x + bounds.width / 2;
           const vcy = bounds.y + bounds.height / 2;
 
-          const imageItems: { item: SceneItem; sprite: ImageSprite | AnimatedGifSprite; dist: number; near: boolean }[] = [];
+          const imageItems: { item: SceneItem; sprite: ImageSprite | AnimatedGifSprite | PdfPageSprite; dist: number; near: boolean }[] = [];
           const videoItems: { item: SceneItem; sprite: VideoSprite; dist: number; near: boolean }[] = [];
 
           // Spatial query: only check items within the extended viewport region
@@ -215,6 +216,8 @@ const PixiCanvas = forwardRef<PixiCanvasHandle, PixiCanvasProps>(
 
             if (item.type === 'image' && (item.displayObject instanceof ImageSprite || item.displayObject instanceof AnimatedGifSprite)) {
               imageItems.push({ item, sprite: item.displayObject, dist, near: true });
+            } else if (item.type === 'pdf-page' && item.displayObject instanceof PdfPageSprite) {
+              imageItems.push({ item, sprite: item.displayObject, dist, near: true });
             } else if (item.type === 'video' && item.displayObject instanceof VideoSprite) {
               videoItems.push({ item, sprite: item.displayObject, dist, near: true });
             }
@@ -257,7 +260,7 @@ const PixiCanvas = forwardRef<PixiCanvasHandle, PixiCanvasProps>(
             const item = scene.items.get(id);
             if (!item) { loadedImages.delete(id); continue; }
             const sprite = item.displayObject;
-            if ((sprite instanceof ImageSprite || sprite instanceof AnimatedGifSprite) && sprite.loaded) {
+            if ((sprite instanceof ImageSprite || sprite instanceof AnimatedGifSprite || sprite instanceof PdfPageSprite) && sprite.loaded) {
               sprite.unloadTexture();
             }
             loadedImages.delete(id);

frontend/src/canvas/SceneManager.ts

@@ -15,6 +15,7 @@ import { DrawingSprite } from './sprites/DrawingSprite';
 import { FrameSprite } from './sprites/FrameSprite';
 import { StickySprite } from './sprites/StickySprite';
 import { MarkdownSprite } from './sprites/MarkdownSprite';
+import { PdfPageSprite } from './sprites/PdfPageSprite';
 import { TextSprite } from './sprites/TextSprite';
 import { SpringManager, Spring, PRESETS } from './spring';
 import { reparentGroupChildren } from './grouping';
@@ -38,6 +39,7 @@ import type {
   GroupObject,
   StickyObject,
   MarkdownObject,
+  PdfPageObject,
 } from './scene-format';
 
 // ---------------------------------------------------------------------------
@@ -374,6 +376,13 @@ export class SceneManager {
         break;
       }
 
+      case 'pdf-page': {
+        const d = data as PdfPageObject;
+        const sprite = new PdfPageSprite(d.thumb, d.asset, d.w, d.h, d.pageNumber, d.pageCount, this.textures);
+        displayObject = sprite;
+        break;
+      }
+
       default:
         displayObject = new Container();
         break;
@@ -710,6 +719,34 @@ export class SceneManager {
     return this.items.get(data.id)!;
   }
 
+  /** Create a PdfPageObject from a PDF upload and add it to the scene. */
+  addPdfPageFromUpload(
+    thumbKey: string | null, assetKey: string | null,
+    w: number, h: number, x: number, y: number,
+    pdfImageId: string, pdfName: string,
+    pageNumber: number, pageCount: number,
+  ): SceneItem {
+    const data: PdfPageObject = {
+      id: crypto.randomUUID(),
+      type: 'pdf-page',
+      x, y, w, h,
+      sx: 1, sy: 1, angle: 0,
+      z: this.nextZ(),
+      opacity: 1,
+      locked: false,
+      visible: true,
+      name: `${pdfName} p.${pageNumber}`,
+      asset: assetKey,
+      thumb: thumbKey,
+      pdfImageId, pdfName, pageNumber, pageCount,
+      nativeW: w, nativeH: h,
+    };
+    this._createItem(data);
+    this._applyZOrder();
+    this._onChange?.();
+    return this.items.get(data.id)!;
+  }
+
   // -- Group / Ungroup with Spring Animation --------------------------------
 
   /**