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 FRAGMENT_SHADER or a VERTEX_SHADER.

precisionType

A precision type value. Either LOW_FLOAT, MEDIUM_FLOAT, HIGH_FLOAT, LOW_INT, MEDIUM_INT, or 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 VERTEX_SHADER with a 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

See also

• WebGLShaderPrecisionFormat