WebGLRenderingContext.sampleCoverage()

The WebGLRenderingContext.sampleCoverage() method of the WebGL API specifies multi-sample coverage parameters for anti-aliasing effects.

Syntax

void gl.sampleCoverage(value, invert);

Parameters

value
A GLclampf which sets a single floating-point coverage value clamped to the range [0,1]. The default value is 1.0.
invert
GLboolean which sets whether or not the coverage masks should be inverted. The default value is false.

Return value

None.

Examples

Multi-sampling is disabled by default. To enable or disable multi-sampling, use the enable() and disable() methods with the argument gl.SAMPLE_COVERAGE and gl.SAMPLE_ALPHA_TO_COVERAGE.

gl.enable(gl.SAMPLE_COVERAGE);
gl.sampleCoverage(0.5, false);

To check the sample coverage values, query the SAMPLE_COVERAGE_VALUE and SAMPLE_COVERAGE_INVERT constants.

gl.getParameter(gl.SAMPLE_COVERAGE_VALUE);  // 0.5
gl.getParameter(gl.SAMPLE_COVERAGE_INVERT); // false

Specifications

Specification Status Comment
WebGL 1.0
The definition of 'sampleCoverage' in that specification.
Recommendation Initial definition.
OpenGL ES 2.0
The definition of 'glSampleCoverage' in that specification.
Standard Man page of the OpenGL API.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support912411125.1
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes25 Yes Yes128.1 Yes

See also

Document Tags and Contributors

Contributors to this page: fscholz, teoli
Last updated by: fscholz,