Arithmetic in blueprint editor

gfaster · Post by **gfaster** » Fri May 15, 2026 6:42 pm

TL;DR

Let us do math like we can in item selection in the blueprint grid size+offset editing boxes

What?

We can already do arithmetic when selecting an item/signal:

: Arithmetic is so convenient; 05-15-2026, 14-29-19.png (11.02 KiB) Viewed 323 times

But it came as a surprise when I couldn't do that when setting the blueprint:

: Why can't I input a `+` here?; 05-15-2026, 14-31-20.png (51.33 KiB) Viewed 323 times

I believe it would be an improvement to allow arithmetic in these fields.

Why?

I often make blueprints, particularly for rails and city blocks, to be close to chunk-aligned. As a result I often know exactly how many tiles offset the blueprint bounds should be (e.g. I know the grid size is 16 tiles on all sides smaller than my selection). Right now I have do the math out in my head or on paper, but that's a limitation that feel arbitrary/like an oversight.

This is a small gap in Factorio's peerless UI design where affordances are very nearly universal. I found not being able to do arithmetic here to be quite surprising.