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
GLboolean gl.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 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
gl.isEnabled(gl.STENCIL_TEST);
// false
To activate or deactivate a specific capability, use the
WebGLRenderingContext.enable()
and
WebGLRenderingContext.disable()
methods:
gl.enable(gl.STENCIL_TEST);
gl.disable(gl.STENCIL_TEST);
Specifications
Specification |
---|
WebGL Specification # 5.14.3 |
WebGL 2.0 Specification # 3.7.2 |
Browser compatibility
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