WebGLRenderingContext: isEnabled() method

Available in workers

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

isEnabled(cap)

Parameters

• cap

  • : A GLenum specifying which WebGL capability to test. Possible values:

    Constant	Description
    gl.BLEND	Blending of the computed fragment color values. See blendFunc().
    gl.CULL_FACE	Culling of polygons. See cullFace().
    gl.DEPTH_TEST	Depth comparisons and updates to the depth buffer. See 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 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 sampleCoverage().
    gl.SCISSOR_TEST	Scissor test that discards fragments that are outside of the scissor rectangle. See scissor().
    gl.STENCIL_TEST	Stencil testing and updates to the stencil buffer. See 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

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

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

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

Specifications

Browser compatibility

See also

• enable()
• disable()