I am trying to have an irregular but repeating grid-like pattern, in absolute scale, in my LaTeX output (think hexagonal grid with fixed edge width of 1 cm when printed; but hundreds/thousands of variations).

What I have tried is to build an SVG with <pattern> using absolute metrics (these I can prepare programmatically),

<svg width="50mm" height="50mm" xmlns="http://www.w3.org/2000/svg">
  <pattern
    id="p3"
    x="0"
    y="0"
    width="5mm"
    height="5mm"
    patternUnits="userSpaceOnUse">
    <circle cx="1mm" cy="1mm" r="1mm" />
    <circle cx="3mm" cy="3mm" r="1mm" />
  </pattern>

  <rect x="0" y="0" stroke="red" width="100%" height="100%" fill="url(#p3)" />
</svg>

then include the graphics (this goes through an intermediary PDF since LaTeX doesn't take SVG).

\includegraphics[page=1, width=3cm]{Figures/fixed_pattern.pdf}
\includegraphics[page=1, width=6cm]{Figures/fixed_pattern.pdf}

The output here is

https://preview.redd.it/mynzc3khbuzb1.png?width=1512&format=png&auto=webp&s=c46f6e39e695ed521633f8d325e7747b231c573b

but I was hoping for a result where the red rectangle is scaled up, yet the size of the dots do not grow bigger (but there is just more repeating units being shown).

Any suggestions for achieving this? (Or other ways of going about flexible "tiling images with *absolute (real-world)* scale", LaTeX or otherwise?)