WebGLRenderingContext.isEnabled()

The WebGLRenderingContext.isEnabled() method of the WebGL API tests whether a specific WebGL capability is enabled or not for this context.

By default, all capabilities except gl.DITHER are disabled.

Syntax

JavaScript
void <var>gl</var>.isEnabled(<var>cap</var>);

Parameters

cap
A GLenum specifying which WebGL capability to test. Possible values:
Constant Description
gl.BLEND Blending of the computed fragment color values. See WebGLRenderingContext.blendFunc().
gl.CULL_FACE Culling of polygons. See WebGLRenderingContext.cullFace().
gl.DEPTH_TEST Depth comparisons and updates to the depth buffer. See WebGLRenderingContext.depthFunc().
gl.DITHER Dithering of color components before they get written to the color buffer.
gl.POLYGON_OFFSET_FILL Adding an offset to depth values of polygon's fragments. See WebGLRenderingContext.polygonOffset().
gl.SAMPLE_ALPHA_TO_COVERAGE Computation of a temporary coverage value determined by the alpha value.
gl.SAMPLE_COVERAGE ANDing the fragment's coverage with the temporary coverage value. See WebGLRenderingContext.sampleCoverage().
gl.SCISSOR_TEST Scissor test that discards fragments that are outside of the scissor rectangle. See WebGLRenderingContext.scissor().
gl.STENCIL_TEST Stencil testing and updates to the stencil buffer. See WebGLRenderingContext.stencilFunc().
When using a WebGL 2 context, the following values are available additionally:
Constant Description
gl.RASTERIZER_DISCARD Primitives are discarded immediately before the rasterization stage, but after the optional transform feedback stage. gl.clear() commands are ignored.

Return value

A GLboolean indicating if the capability cap is enabled (true), or not (false).

Examples

JavaScript
gl.isEnabled(gl.STENCIL_TEST); 
// false

To activate or deactivate a specific capability, use the WebGLRenderingContext.enable() and  WebGLRenderingContext.disable() methods:

JavaScript
gl.enable(gl.STENCIL_TEST);
gl.disable(gl.STENCIL_TEST);

Specifications

Specification Status Comment
WebGL 1.0
The definition of 'isEnabled' in that specification.
Recommendation Initial definition for WebGL.
OpenGL ES 2.0
The definition of 'glIsEnabled' in that specification.
Standard Man page of the (similar) OpenGL ES 2.0 API.
WebGL 2.0
The definition of 'isEnabled' in that specification.
Editor's Draft Updated definition for WebGL 2.
OpenGL ES 3.0
The definition of 'glIsEnabled' in that specification.
Standard Man page of the (similar) OpenGL ES 3.0 API.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 9 4.0 (2.0) 11 12 5.1
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? 25 (Yes) ? 12 8.1

See also

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/webglrenderingcontext/isenabled

API Method Reference WebGL WebGLRenderingContext