WebGLRenderingContext.getShaderPrecisionFormat()

The WebGLRenderingContext.getShaderPrecisionFormat() method of the WebGL API returns a new WebGLShaderPrecisionFormat object describing the range and precision for the specified shader numeric format.

Syntax

WebGLShaderPrecisionFormat gl.getShaderPrecisionFormat(shaderType, precisionType);

Parameters

shaderType
Either a gl.FRAGMENT_SHADER or a gl.VERTEX_SHADER.
precisionType
A precision type value. Either gl.LOW_FLOAT, gl.MEDIUM_FLOAT, gl.HIGH_FLOAT, gl.LOW_INT, gl.MEDIUM_INT, or gl.HIGH_INT.

Return value

A WebGLShaderPrecisionFormat object or null, if an error occurs.

Exceptions

  • gl.INVALID_ENUM if the shader or precision types aren't recognized.
  • gl.INVALID_OPERATION if the shader compiler isn't supported.

Examples

The following code gets the precision format of a gl.VERTEX_SHADER with a gl.MEDIUM_FLOAT precision type.

var canvas = document.getElementById('canvas');
var gl = canvas.getContext('webgl');

gl.getShaderPrecisionFormat(gl.VERTEX_SHADER, gl.MEDIUM_FLOAT);
// WebGLShaderPrecisionFormat { rangeMin: 127, rangeMax: 127, precision: 23 }

Specifications

Specification Status Comment
WebGL 1.0
The definition of 'getShaderPrecisionFormat' in that specification.
Recommendation Initial definition.
OpenGL ES 2.0
The definition of 'glGetShaderPrecisionFormat' in that specification.
Standard Man page of the (similar) OpenGL API.

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
getShaderPrecisionFormatChrome Full support 9Edge Full support 12Firefox Full support 4IE Full support 11Opera Full support 12Safari Full support 5.1WebView Android Full support YesChrome Android Full support 25Firefox Android Full support YesOpera Android Full support 12Safari iOS Full support 8Samsung Internet Android Full support 1.5

Legend

Full support
Full support

See also