{
  "id": 8139609,
  "title": "Splitting a large image across multiple printed pages without alignment marks",
  "url": "https://urgent.news/2026/09/18/splitting-a-large-image-across-multiple-printed-pages-without",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-09-18T00:46:00.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/nongyi531415/splitting-a-large-image-across-multiple-printed-pages-without-alignment-marks-115c"
  },
  "original_language": "en",
  "account": "I recently added tiled printing functionality to a small tool called ArtGrid, which allows users to print a large image across multiple A4 sheets and tape them together. The naive approach is to slice the enlarged image into a grid of page-sized rectangles and export each as a separate PDF page. However, aligning the pieces on paper can be challenging due to printer scaling errors, which compound across each seam. To avoid the need for alignment marks, I changed where the cuts land by cutting on lines that are already present in the grid. By forcing every page boundary to land exactly on a grid line, there is no need for trimming since the join is a continuation of a mark that would have been drawn anyway. The key constraint is that the cell size must be square, as non-square cells would not provide a fixed unit for tiling and would require alignment marks once again. The implementation involves calculating the number of columns and rows that fit on a single page based on the printable area and dividing the total number of columns and rows by these values to determine the number of pages needed. A simple assertion was written to test if the reconstructed printable rectangle from all the tiles matches the original enlarged rectangle to within a millimeter, ensuring the accuracy of the tiled print. The tool can be tested at griddrawing.org/print-large-image-multiple-pages, where a static client-side version is available with a printed ruler for calibration.",
  "summary": "I recently added tiled printing to a small static tool I run ( ArtGrid ) — the kind of \"print a big image across several A4 sheets and tape them together\" feature you've probably seen in poster-printing tools. The naive version is easy: slice the enlarged image into a grid of page-sized rectangles, export each as a PDF page. The annoying version is making the pieces line back up on paper, where a…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}