The <line> SVG element is an SVG basic shape used to create a line connecting two points.

The addition (+) operator produces the sum of numeric operands or string concatenation.

The <feFuncB> SVG filter primitive defines the transfer function for the blue component of the input graphic of its parent <feComponentTransfer> element.

The <ellipse> SVG element is an SVG basic shape, used to create ellipses based on a center coordinate, and both their x and y radius.

The <feSpecularLighting> SVG filter primitive lights a source graphic using the alpha channel as a bump map. The resulting image is an RGBA image based on the light color. The lighting calculation follows the standard specular component of the Phong lighting model. The resulting image depends on the light color, light position and surface geometry of the input bump map. The result of the lighting calculation is added. The filter primitive assumes that the viewer is at infinity in the z direction.

The decodeURI() function decodes a Uniform Resource Identifier (URI) previously created by encodeURI() or a similar routine.

The pointsAtZ attribute represents the z location in the coordinate system established by attribute primitiveUnits on the <filter> element of the point at which the light source is pointing, assuming that, in the initial local coordinate system, the positive z-axis comes out towards the person viewing the content and assuming that one unit along the z-axis equals one unit in x and y.

The JavaScript exception "invalid regexp group" occurs when the sequence (? does not start a valid group syntax. Recognized group syntaxes that start with (? include:

The preserveAspectRatio attribute indicates how an element with a viewBox providing a given aspect ratio must fit into a viewport with a different aspect ratio.

The style attribute allows to style an element using CSS declarations. It functions identically to the style attribute in HTML.