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EXT disjoint timer query

The EXT_disjoint_timer_query extension is part of the WebGL API and provides a way to measure the duration of a set of GL commands, without stalling the rendering pipeline.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

Availability: This extension should be available in WebGL1 contexts only. EXT_disjoint_timer_query_webgl2 is available in WebGL 2 contexts .

In WebGL 2, the getQueryObject was renamed to getQueryParameter.
In WebGL 2, other queries (such as occlusion queries and primitive queries) are possible using WebGLQuery objects.

Types

This extension exposes a new type:

GLuint64EXT: Unsigned 64-bit integer number.

Constants

This extension exposes seven new constants.

ext.QUERY_COUNTER_BITS_EXT: A GLint indicating the number of bits used to hold the query result for the given target.
ext.CURRENT_QUERY_EXT: A WebGLQuery object, which is the currently active query for the given target.
ext.QUERY_RESULT_EXT: A GLuint64EXT containing the query result.
ext.QUERY_RESULT_AVAILABLE_EXT: A GLboolean indicating whether or not a query result is available.
ext.TIME_ELAPSED_EXT: Elapsed time (in nanoseconds).
ext.TIMESTAMP_EXT: The current time.
ext.GPU_DISJOINT_EXT: A GLboolean indicating whether or not the GPU performed any disjoint operation.

Methods

This extension exposes eight new methods.

ext.createQueryEXT(): Creates a new WebGLQuery.
ext.deleteQueryEXT(): Deletes a given WebGLQuery.
ext.isQueryEXT(): Returns true if a given object is a WebGLQuery.
ext.beginQueryEXT(): The timer starts when all commands prior to beginQueryEXT have been fully executed.
ext.endQueryEXT(): The timer stops when all commands prior to endQueryEXT have been fully executed.
ext.queryCounterEXT(): Records the current time into the corresponding query object.
ext.getQueryEXT(): Returns information about a query target.
ext.getQueryObjectEXT(): Return the state of a query object.

Examples

var ext = gl.getExtension('EXT_disjoint_timer_query');

Specifications

Specification	Status	Comment
EXT_disjoint_timer_query The definition of 'EXT_disjoint_timer_query' in that specification.	Working Draft	Initial definition.

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`createQueryEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`deleteQueryEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`isQueryEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`beginQueryEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`endQueryEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`queryCounterEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`getQueryEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?
`getQueryObjectEXT`	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	51 — 63 51 — 63 Removed due to the GLitch exploit.	?	?	?

	Mobile
	Android webview	Chrome for Android	Edge Mobile	Firefox for Android	Opera for Android	iOS Safari	Samsung Internet
Basic support	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`createQueryEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`deleteQueryEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`isQueryEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`beginQueryEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`endQueryEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`queryCounterEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`getQueryEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0
`getQueryObjectEXT`	?	47 — 65 47 — 65 Removed due to the GLitch exploit.	No	No	?	?	5.0