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WebGLRenderingContext: isEnabled() method

files/en-us/web/api/webglrenderingcontext/isenabled/index.md

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{{APIRef("WebGL")}}{{AvailableInWorkers}}

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

js-nolint
isEnabled(cap)

Parameters

  • cap
    • : A {{domxref("WebGL_API/Types", "GLenum")}} specifying which WebGL capability to test. Possible values:

      ConstantDescription
      gl.BLENDBlending of the computed fragment color values. See {{domxref("WebGLRenderingContext.blendFunc()")}}.
      gl.CULL_FACECulling of polygons. See {{domxref("WebGLRenderingContext.cullFace()")}}.
      gl.DEPTH_TESTDepth comparisons and updates to the depth buffer. See {{domxref("WebGLRenderingContext.depthFunc()")}}.
      gl.DITHERDithering of color components before they get written to the color buffer.
      gl.POLYGON_OFFSET_FILLAdding an offset to depth values of polygon's fragments. See {{domxref("WebGLRenderingContext.polygonOffset()")}}.
      gl.SAMPLE_ALPHA_TO_COVERAGEComputation of a temporary coverage value determined by the alpha value.
      gl.SAMPLE_COVERAGEANDing the fragment's coverage with the temporary coverage value. See {{domxref("WebGLRenderingContext.sampleCoverage()")}}.
      gl.SCISSOR_TESTScissor test that discards fragments that are outside of the scissor rectangle. See {{domxref("WebGLRenderingContext.scissor()")}}.
      gl.STENCIL_TESTStencil testing and updates to the stencil buffer. See {{domxref("WebGLRenderingContext.stencilFunc()")}}.

      When using a {{domxref("WebGL2RenderingContext", "WebGL 2 context", "", 1)}}, the following values are available additionally:

      ConstantDescription
      gl.RASTERIZER_DISCARDPrimitives are discarded immediately before the rasterization stage, but after the optional transform feedback stage. gl.clear() commands are ignored.

Return value

A {{domxref("WebGL_API/Types", "GLboolean")}} indicating if the capability cap is enabled (true), or not (false).

Examples

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

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

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

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

  • {{domxref("WebGLRenderingContext.enable()")}}
  • {{domxref("WebGLRenderingContext.disable()")}}