Choosing a page and grid¶

The page, the margins and the grids need to agree with each other. Settle them first; modules added afterwards line up on their own.

Page size¶

A name or millimetres:

page:
  size: a6                # 105 × 148
  # size: [105, 170]      # width, height

Names: a4, a5, a6, a7, b6, letter, half-letter, pocket (89 × 140), hobonichi-weeks (95 × 188). See units.

For a bound book, use the trimmed page size, not the sheet you print on.

Margins¶

page:
  margins:
    top: 2.5
    bottom: 7.5
    inner: 15          # binding side
    outer: 5

inner and outer are named by their relation to the spine. A template's side: right or side: left decides which becomes left and right. Set left and right instead to turn mirroring off. margins: {all: 10} sets all four; named keys override it.

The module grid¶

Every module's position and size snaps to it. 2.5 mm and 2 mm are both reasonable; 2 mm gives finer control over row heights.

grid:
  module: 2.5

A height you write that is off the grid is snapped, with a warning. A module's own intrinsic height is snapped silently.

The dot lattice¶

Dots are a separate, coarser grid, anchored to the page rather than to any module, so dots in one box line up with dots in the next.

grid:
  dots:
    spacing: 5
    origin: [0, 2.5]     # the lattice passes through x ≡ 0, y ≡ 2.5 (mm)
    radius: 0.125

Make spacing a multiple of module and put origin half a step off, so a module edge never lands on a dot row. The defaults do this.

Check they divide¶

Both grids are anchored to the page, so for the content rectangle to sit on the module grid on both sides of a spread:

inner must be a multiple of the grid (it is the left margin on a recto);
outer must be too (it is the left margin on a verso);
the page width must be as well, since the content width is page − inner − outer.

page width	grid
105 mm	2.5	yes: 42 steps
105 mm	2	no: 52.5 steps, one margin must be odd
148 mm (a5)	2	yes: 74 steps
148 mm (a5)	2.5	no: 59.2 steps

If you accept a page that doesn't divide, one side's content rectangle sits off the lattice. journalkit check reports that as a per-page note and checks module placements relative to the rectangle, so a module that actually drifts still fails. See the two grids.

Look¶

journalkit build --png --debug

Blue lines are the module grid; the pink dashed box is the content rectangle. If its edges sit on blue lines on both a recto and a verso, the page and grid agree.