Module kas::layout

Layout solver

Size units are physical (real) pixels. This applies to most of KAS.

Data types

SizeRules is the "heart" of widget layout, used to specify a widget's size requirements. It provides various methods to compute derived rules and SizeRules::solve_seq, the "muscle" of the layout engine.

AxisInfo, Margins and StretchPolicy are auxilliary data types.

Layout engines

The RulesSolver and RulesSetter traits define interfaces for layout engines:

• SingleSolver and SingleSetter are trivial implementations for single-child parents
• RowSolver and RowSetter set out a row or column of children. These are parametrised over S: RowStorage allowing both efficient operation on a small fixed number of children with FixedRowStorage and operation on a over a Vec with DynRowStorage.
• GridSolver and GridSetter set out children assigned to grid cells with optional cell-spans. This is the most powerful and flexible layout engine.

RowPositionSolver may be used with widgets set out by RowSetter to quickly locate children from a coord or rect.

Structs

AxisInfo	Information on which axis is being resized
DynGridStorage	Variable-length grid storage
DynRowStorage	Variable-length row storage
FixedGridStorage	Fixed-length grid storage
FixedRowStorage	Fixed-length row storage
GridChildInfo	Per-child information
GridSetter	A RulesSetter for grids supporting cell-spans
GridSolver	A RulesSolver for grids supporting cell-spans
Margins	Margin sizes
RowPositionSolver	Allows efficient implementations of draw / event handlers based on the layout representation.
RowSetter	A RulesSetter for rows (and, without loss of generality, for columns).
RowSolver	A RulesSolver for rows (and, without loss of generality, for columns).
SingleSetter	RulesSetter implementation for a fixed single-child layout
SingleSolver	RulesSolver implementation for a fixed single-child layout
SizeRules	Widget sizing information
SolveCache	Size solver

Enums

StretchPolicy

Policy for stretching widgets beyond ideal size

Traits

GridStorage	Requirements of grid solver storage type
RowStorage	Requirements of row solver storage type
RowTemp	Temporary storage type.
RulesSetter	Resolves a RulesSolver solution for each child
RulesSolver	A SizeRules solver for layouts
Storage	Master trait over storage types