Grid

Grid is track-based placement on two axes. You declare column and row tracks, then add children that occupy one or more slots.

two columns, two rows

three columns

use Atelier\Layout\Element\Grid;
use Atelier\Layout\Geometry\Rect;
use Atelier\Layout\Grid\TrackSize;
use Atelier\Layout\LayoutContext;

$grid = Grid::tracks('items', [TrackSize::fr(), TrackSize::fr()])
    ->rows([TrackSize::fixed(40), TrackSize::fr()])
    ->gap(12)
    ->add($header, columnSpan: 2)
    ->add($left)
    ->add($right);

$solved = $grid->solve(new LayoutContext(), Rect::fromSize(400, 240));

Grid::columns('id', 3) is the short form when every column is an equal fraction.

Track Sizes

Constructor	Meaning
`TrackSize::fixed(float $px)`	an exact number of pixels
`TrackSize::fr(float $fraction = 1.0)`	a share of the space left after fixed and auto tracks
`TrackSize::auto()`	sized to the content it holds

Fixed tracks are resolved first, auto tracks next, and fraction tracks share whatever remains in proportion to their fraction. A grid narrower than the sum of its fixed tracks does not shrink them.

Spans

add() takes columnSpan and rowSpan. A spanning child covers the slots plus the gaps between them, so a title spanning two columns is wider than the two columns it covers by exactly one gap.

columnSpan: 2

rowSpan: 2

Empty Slots

Children fill slots in the order they are added, left to right then top to bottom. There is no explicit slot addressing: to leave a hole, add a child that draws nothing, or reorder the tracks so the hole falls at the end.

Alignment Inside Slots

align() sets the alignment used by every slot; add() overrides it per item through alignX and alignY.

use Atelier\Layout\Alignment;

Grid::tracks('items', [TrackSize::fr(), TrackSize::fr()])
    ->align(Alignment::Center, Alignment::Center)
    ->add($left)
    ->add($right, alignX: Alignment::End);

A child aligned Stretch fills its slot. A Frame::fixed() ignores Stretch and keeps its declared size.