UNode and Box Metrics

UNode is the fundamental building block of every UI element.

Main Fields

• width
• height
• min_width
• max_width
• min_height
• max_height
• padding
• margin
• background_color
• border_radius
• shape_mode

Supported units:

• UVal::Px
• UVal::Percent
• UVal::MinContent
• UVal::MaxContent
• UVal::Content
• UVal::Auto
• UVal::Flex

Sizing Notes

• width and height are the preferred size request.
• min_width, max_width, min_height, and max_height clamp the solved result.
• padding participates in intrinsic measurement, while margin affects placement and wrap span rather than the node’s inner measured content.
• UVal::Content is the legacy alias for UVal::MaxContent.
• UVal::Auto is contextual rather than identical to Content.
• Use MaxContent or MinContent when you want explicit intrinsic sizing without implicit auto-stretch behavior.
• border_radius and shape_mode stay visual-only; they do not change the measured layout size by themselves.

See Sizing Semantics for the current detailed rules.

Final Size

After layout solving, every entity receives:

• ComputedSize

That final size is what rendering uses.

UBorder

Borders are visually separate from the UNode background and support:

• width
• color
• rounded corners

Shape Modes

• Round: rounded SDF corners
• Cut: beveled or cut corners