fix: apply offset when pre-registered fallback has no paragraph context

Author: VladaHarbour

packages/layout-engine/contracts/src/graphic-placement.test.ts

@@ -52,6 +52,24 @@ describe('resolveAnchoredGraphicY', () => {
     ).toBe(92);
   });
 
+  it('ignores paragraph alignV when pre-registered fallback has no paragraph context', () => {
+    expect(
+      resolveAnchoredGraphicY({
+        ...base,
+        anchor: { vRelativeFrom: 'paragraph', alignV: 'center', offsetV: 0 },
+        preRegisteredFallbackToContentTop: true,
+      }),
+    ).toBe(72);
+    expect(
+      resolveAnchoredGraphicY({
+        ...base,
+        objectHeight: 50,
+        anchor: { vRelativeFrom: 'paragraph', alignV: 'bottom', offsetV: 10 },
+        preRegisteredFallbackToContentTop: true,
+      }),
+    ).toBe(82);
+  });
+
   it('legacy undefined vRelativeFrom uses anchor paragraph Y', () => {
     expect(
       resolveAnchoredGraphicY({

packages/layout-engine/contracts/src/graphic-placement.ts

@@ -33,8 +33,9 @@ export type ResolveAnchoredGraphicYInput = {
   /** First line height of the anchor paragraph (paragraph-relative alignV). */
   firstLineHeight?: number;
   /**
-   * When true and vRelativeFrom is not margin/page, fall back to contentTop + offsetV
-   * (page/margin pre-registered anchors that lack paragraph context).
+   * When true, anchor has no host paragraph (pre-registered / paragraphless layout).
+   * For `vRelativeFrom: 'paragraph'`, use `contentTop + offsetV` instead of alignV on a
+   * synthetic paragraph (defaults would wrongly center/bottom against contentTop).
    */
   preRegisteredFallbackToContentTop?: boolean;
 };
@@ -81,6 +82,9 @@ export function resolveAnchoredGraphicY(input: ResolveAnchoredGraphicYInput): nu
   }
 
   if (vRelativeFrom === 'paragraph') {
+    if (preRegisteredFallbackToContentTop) {
+      return contentTop + offsetV;
+    }
     const baseAnchorY = anchorParagraphY;
     if (alignV === 'bottom') {
       return baseAnchorY + firstLineHeight - objectHeight + offsetV;