Input events such as pointermove, mousemove and touchmove may be dispatched at an appropriate time to reduce the amount of unncessary work. Reducing the amount of work comes at a cost of increasing latency sometimes. This increase in latency may not be a desirable side effect for some applications. Adding the ability for an application to indicate that they require low latency input is desired.
As described in the event-loop explainer continuous events MAY be held and dispatched in the render part of the event loop. Indicating lowlatency: true SHOULD cause these continuous events to be dispatched right away instead of waiting on the render part of the event loop. Setting lowlatency on non-continuous events MUST NOT have any event on processing.
Conformance
Conformance requirements are expressed with a combination of descriptive assertions and RFC 2119 terminology.
The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL”
in the normative parts of this document
are to be interpreted as described in RFC 2119.
However, for readability,
these words do not appear in all uppercase letters in this specification.
All of the text of this specification is normative
except sections explicitly marked as non-normative, examples, and notes. [RFC2119]
Examples in this specification are introduced with the words “for example”
or are set apart from the normative text with class="example", like this:
This is an example of an informative example.
Informative notes begin with the word “Note”
and are set apart from the normative text with class="note", like this: