Layout Helpers

Utility functions for common layout patterns.

See the tecs-ui example.

stackVertical

Position children in a vertical stack:

local ui = require("tecs2d.ui")

-- Stack with 10px spacing, starting at Y=0
ui.stackVertical(world, {child1, child2, child3}, 10)

-- Stack starting at Y=50
ui.stackVertical(world, children, 10, 50)

Children must have RelativeTransform and optionally LayoutBox components. The function updates each child's RelativeTransform.y based on the cumulative heights of preceding children.

stackHorizontal

Position children in a horizontal row:

-- Row with 10px spacing, starting at X=0
ui.stackHorizontal(world, {child1, child2, child3}, 10)

-- Row starting at X=20
ui.stackHorizontal(world, children, 10, 20)

measureContent

Calculate the bounding box of children:

local width, height = ui.measureContent(world, children)

Returns the total width and height needed to contain all children based on their RelativeTransform positions and LayoutBox dimensions. Useful for sizing containers to fit their content.