scaleX2

ScaleX2 is a term used in some mathematical and graphical contexts to denote a twofold scaling of the x-coordinate in a two-dimensional space. It is not a universally standardized name, but serves as shorthand in discussions or codebases where a specific horizontal stretch by a factor of two is being described.

In mathematical terms, scaleX2 is the linear transformation that maps a point (x, y) to (2x, y). In matrix form, this can be represented by the 2x2 matrix [[2, 0], [0, 1]]. In homogeneous coordinates, the corresponding 3x3 affine transformation is [[2, 0, 0], [0, 1, 0], [0, 0, 1]]. The transformation is linear and invertible, with an inverse that scales by 1/2 along the x-axis. Its determinant is 2, indicating that the transformation doubles the area of any region it acts upon.

The effect of scaleX2 is to stretch objects horizontally by a factor of two while leaving their vertical dimensions unchanged. Shapes become wider without increasing height, and angles are preserved only for pure horizontal scaling when applied alone. When scaleX2 is combined with other transformations such as translations, rotations, or vertical scaling, the overall effect depends on the order of operations due to properties of affine transformations.

Implementation and usage vary by platform. In general software practice, a horizontal double scale is achieved with a function or command analogous to scaleX(2). Some libraries or documentation may use the specific name scaleX2 as a shorthand, but this is not a standard across graphics systems. In CSS, for example, the equivalent is transform: scaleX(2); in SVG, a similar effect can be achieved with transform="scale(2,1)".