getMediaBox()/getCropBox() return raw x2/y2 as width/height for non-zero-origin boxes

[alfikiafan]

Environments

LibPDF version: 0.4.0
Node version: v24.11.1

Minimal reproduction

import { PDF, PdfArray, PdfNumber } from "@libpdf/core";

const pdf = PDF.create();
const page = pdf.addPage({ width: 400, height: 600 });

// Simulate a box with a non-zero origin (e.g. a page that has already been cropped once)
page.dict.set("MediaBox", new PdfArray([
  PdfNumber.of(10),
  PdfNumber.of(25),
  PdfNumber.of(380),
  PdfNumber.of(550),
]));

console.log(page.getMediaBox());
// { x: 10, y: 25, width: 380, height: 550 }

Expected behavior

width/height should be the box's actual dimensions: width = x2 - x1 = 370, height = y2 - y1 = 525.

Actual behavior

width/height are the raw x2/y2 array values (380, 550), not the computed box size. This only manifests when the box's origin isn't (0, 0) — e.g. a page that has already been cropped once — so it's easy to miss in testing, since x2 - 0 === x2.

Likely cause

getBox() in dist/index.mjs (~line 28265) returns { x: x1.value, y: y1.value, width: x2.value, height: y2.value } without subtracting the origin. This affects getMediaBox(), getCropBox(), and their fallbacks getBleedBox()/getTrimBox()/getArtBox().