The baseVal property of the SVGAnimatedBoolean interface is the value of the associated animatable boolean SVG attribute in its base (none-animated) state. It reflects the value of the associated animatable boolean attribute when no animations are applied.
Some boolean SVG attributes, such as preserveAlpha, are animatable. In such cases, SVGAnimatedBoolean.baseVal property is false when the attribute is set to false, is omitted and defaults to false, or is inheritable and inherits false. Otherwise, the value is true.
A boolean; the base value of the reflected attribute.