DOMMatrix: scaleSelf() method

The scaleSelf() method of the DOMMatrix interface is a mutable transformation method that modifies a matrix by applying a specified scaling factor, centered on the given origin, with a default origin of (0, 0), returning the scaled matrix.

To scale a matrix without mutating it, see DOMMatrixReadOnly.scale(), which creates a new scaled matrix while leaving the original unchanged.

Syntax

scaleSelf()
scaleSelf(scaleX)
scaleSelf(scaleX, scaleY)
scaleSelf(scaleX, scaleY, scaleZ)
scaleSelf(scaleX, scaleY, scaleZ, originX)
scaleSelf(scaleX, scaleY, scaleZ, originX, originY)
scaleSelf(scaleX, scaleY, scaleZ, originX, originY, originZ)

Parameters

scaleX Optional

A multiplier for the scale value on the x-axis. If not supplied, this defaults to 1.

scaleY Optional

A multiplier for the scale value on the y-axis. If not supplied, this defaults to the value of scaleX.

scaleZ Optional

A multiplier for the scale value on the z-axis. If this value is anything other than 1, the resulting matrix will be 3D.

originX Optional

An x-coordinate for the origin of the transformation. If no origin is supplied, this defaults to 0.

originY Optional

A y-coordinate for the origin of the transformation. If no origin is supplied, this defaults to 0.

originZ Optional

A z-coordinate for the origin of the transformation. If no origin is supplied, this defaults to 0. If this value is anything other than 0, the resulting matrix will be 3D.

Return value

Returns itself; a DOMMatrix.

If a scale is applied about the z-axis, the matrix will be a 4✕4 3D matrix.

Examples

This SVG contains two semi-opaque squares, one red and one blue, each positioned at the document origin:

<svg viewBox="0 0 50 50" height="200">
  <rect width="25" height="25" fill="#ff000099" />
  <rect id="transformed" width="25" height="25" fill="#0000ff99" />
</svg>

This JavaScript first creates a matrix, then scales the matrix to one that halves the width and doubles the height, using the scaleSelf() method.

The matrix is then applied to the blue square as a transform, changing its dimensions and position. The red square is left unchanged.

const matrix = new DOMMatrix();
matrix.scaleSelf(0.5, 2);

document
  .querySelector("#transformed")
  .setAttribute("transform", matrix.toString());

Specifications

Browser compatibility

See also

• DOMMatrixReadOnly.scale()
• DOMMatrix.scale3dSelf()
• CSS transform property and the scaleSelf() and matrix() functions
• CSS transforms module
• SVG transform attribute
• CanvasRenderingContext2D interface transform() method