sizefrom

SizeFrom is a term used in computer graphics, animation, and user interface design to describe the origin or reference size from which an element’s dimensions are derived during resizing or transitions. It defines the starting point for size calculations, contrasting with the target size or final dimensions. Depending on the context, sizeFrom can be expressed as an absolute unit (such as pixels), a relative factor (such as a percentage of a base size or container), or a computed value based on surrounding dimensions.

In animation systems, sizeFrom specifies the initial size before a transition to a target size occurs. In responsive layouts and scalable UI components, a sizeFrom value can serve as the baseline for proportional scaling as container sizes change. In image and canvas processing, sizeFrom may indicate the original or reference size used to compute subsequent scaling while preserving aspect ratio or fitting within constraints.

Values for sizeFrom are typically numeric, a percentage, or a named keyword such as "auto" or "initial" in some libraries. It is often used in tandem with a corresponding sizeTo (the end size) and a duration for the transition. Practical considerations include maintaining aspect ratio, respecting layout constraints, and ensuring performance for smooth transitions.

Examples of usage include animating a panel from 60% of its final width to 100% (sizeFrom = 0.6, sizeTo = 1.0) or scaling an image from its original size as sizeFrom to fit within a viewport. See also: sizeTo, scale, resize, transform.