ConstrainDouble type is used to specify a constraint for a property whose value is a double-precision floating-point number. It extends the
DoubleRange dictionary (which provides the ability to specify a permitted range of property values) to also support an exact value and/or an ideal value the property should take on. Additionally, you can specify the property's value as a simple floating-point value, in which case the user agent does its best to match the value once all other more stringent constraints are met.
If the value of a
ConstrainDouble is an object rather than a number, it may have the properties below in addition the properties it inherits from
- A double-precision floating-point number specifying a specific, required, value the property must have to be considered acceptable.
- A double-precision floating-point number specifying a value the property would ideally have, but which can be considered optional if necessary to find a match.
|Media Capture and Streams
The definition of 'ConstrainDouble' in that specification.
|Editor's Draft||Initial definition|
ConstrainDouble is actually based on an intermediary dictionary named
ConstrainDoubleRange, which adds
ConstrainDouble being a type that can be either a long integer or a
DoubleRange. However, for the sake of documentation clarity, the intermediate type (present only because of quirks in WebIDL syntax) is ignored here.
|Feature||Chrome||Firefox (Gecko)||Internet Explorer||Microsoft Edge||Opera||Safari (WebKit)|
|Basic support||(Yes)||50 (50)||No support||?||No support||?|
|Feature||Android||Android Webview||Firefox Mobile (Gecko)||IE Phone||Opera Mobile||Safari Mobile||Chrome for Android|
|Basic support||?||(Yes)||50.0 (50)||No support||No support||?||(Yes)|