The MediaTrackSettings
dictionary's logicalSurface
property indicates whether or not the display area being captured is a logical surface. Logical surfaces are those which are not necessarily entirely onscreen, or may even be off-screen, such as windows' backing buffers (where only part of the buffer is visible without scrolling the containing window) and offscreen rendering contexts.
Syntax
isLogicalSurface = mediaTrackSettings.logicalSurface;
Value
A Boolean value which is true
if the video track in the stream of captured video is taken from a logical display surface.
The most common scenario in which a display surface may be a logical one is if the selected surface contains the entire content area of a window which is too large to display onscreen at once. Since the window that contains the surface has to be scrolled to show the rest of the contents, the surface is a logical one.
A visible display surface (that is, a surface for which logicalSurface
returns false
) is the portion of a logical display surface which is currently visible onscreen.
For example, a user agent may choose to allow the user to choose whether to share the entire document (a browser
with logicalSurface
value of true
), or just the currently visible portion of the document (where the logicalSurface
of the browser
surface is false
).
Specifications
Specification | Status | Comment |
---|---|---|
Screen Capture The definition of 'MediaTrackSettings.logicalSurface' in that specification. |
Working Draft | Initial definition |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
logicalSurface | Chrome Full support 71 | Edge Full support ≤79 | Firefox No support No | IE No support No | Opera Full support Yes | Safari ? | WebView Android Full support 71 | Chrome Android Full support 71 | Firefox Android No support No | Opera Android ? | Safari iOS ? | Samsung Internet Android Full support 10.0 |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown