ivy-ui

Provides a fully fledged UI system for the Ivy framework.

Each UI element is composed of several components. See crate::constraints.

Positioning

The different UI widgets are positioned using constraints.

constraints::AbsoluteOffset specifies an offset in pixels from the parent.

constraints::RelativeOffset specifies an offset proportional to the size of the parent. (1.0, 1.0) specifies the top right corner, and (-1.0, -1.0) specifies the bottom left corner. This coordinate system is also known as normalized device coordinates. These constraints can be combined and will be applied one after another by attaching them both to an entity.

constraints::RelativeSize size is relative to the parent size. A value larger than 1.0 signifies that the child is larger than the parent.

constraints::AbsoluteSize size is given in absolute pixels. If combined with crate::constraints::RelativeSize the result is additive. It is possible to supply a negative absolute size if a relative size is used as it will subtract from the parent size. This can be used to specify 50% of parent size, but 10 pixels smaller. This is useful for margins.

constraints::Aspect force the width to be dependent on the height.

constraints::Origin2D by default, widgets are positioned by their center. The origin specifies an offset relative to the own size. For example, (1.0, 1.0) moves the widget to be positioned in respect to the top right.