WebGLQuery

The WebGLQuery interface is part of the WebGL 2 API and provides ways to asynchronously query for information. By default, occlusion queries and primitive queries are available.

Another kind of queries are disjoint timer queries, which allow you to measure performance and profiling of your GPU. Disjoint timer queries are available with the EXT_disjoint_timer_query extension only.

When working with WebGLQuery objects, the following methods of the WebGL2RenderingContext are useful:

• WebGL2RenderingContext.createQuery()
• WebGL2RenderingContext.deleteQuery()
• WebGL2RenderingContext.isQuery()
• WebGL2RenderingContext.beginQuery()
• WebGL2RenderingContext.endQuery()
• WebGL2RenderingContext.getQuery()
• WebGL2RenderingContext.getQueryParameter()

in this example, gl must be a WebGL2RenderingContext. WebGLQuery objects are not available in WebGL 1.

var query = gl.createQuery();

• EXT_disjoint_timer_query