rumlayout

Rumlayout is a term used in user interface design to describe a class of layout systems that rely on declarative constraints, rules, and adaptive sizing to determine the placement and sizing of UI elements. In rumlayout, elements declare relationships to other elements or to the container via constraints (for example, a width equal to 50% of the container, or the top edge aligned with another element). A rumlayout solver computes concrete positions and sizes by solving the constraint network, and the rendering layer then displays the resulting layout.

Key features include constraints-based sizing with support for fixed, intrinsic, and relative sizing; anchoring and relational constraints; priorities or weights to resolve conflicts; support for aspect ratios, minimum and maximum sizes; responsive behavior across breakpoints; and support for stacking, wrapping, and overflow handling. Rumlayout can be implemented as part of a UI toolkit for web, desktop, or mobile apps, often using a domain-specific language or configuration format to express constraints. Solvers may draw on classical constraint-solving techniques, adapted for modern UI needs.

Compared with imperative layout approaches, rumlayout aims for more predictable behavior under size changes and greater composability of constraints, at the potential cost of increased solving time and debugging complexity. It emphasizes predictable reflow and alignment across varying screen sizes, while requiring careful constraint design to avoid over-constraining the system.

History and usage: The concept arises in discussions of responsive design and constraint-based layouts, drawing on prior research in constraint solving and layout algorithms. It appears in niche toolchains and conceptual explorations rather than as a universally standardized or widely adopted framework.

See also: Constraint-based layout, Cassowary, Auto Layout, Flexbox, Grid layout, Responsive design.