ScaleYfactor

ScaleYfactor is a term used in computer graphics and user interface design to describe the multiplicative factor applied to the vertical dimension of a graphical object. It is commonly used together with scaleX to perform non-uniform scaling, where horizontal and vertical sizes change at different rates.

Mathematically, scaling by scaleYfactor s transforms coordinates by y' = s*y while x' = x if only vertical scaling is applied. In practice, scaling can be applied in local object space or in world space, and the effect can depend on axis orientation; in many graphics systems the Y axis grows upward, while in screen coordinates it often grows downward.

In CSS, the scaleY function is used as part of the transform property, e.g., transform: scaleY(1.5) to enlarge height by 50%. A negative scaleYfactor reverses the vertical orientation, effectively flipping the element around the horizontal axis.

In 3D engines and game development, scaleYfactor corresponds to the y component of an object's scale vector, such as localScale.y in Unity. Non-uniform scaling can affect lighting, shading, collision detection, and texture mapping, so it is used with consideration of the object's geometry and animations.

See also: scaleX, affine transformation, transform matrix.