WebGL2RenderingContext.getActiveUniforms()

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The WebGL2RenderingContext.getActiveUniforms() method of the WebGL 2 API retrieves information about active uniforms within a WebGLProgram.

Syntax

any gl.getActiveUniforms(program, uniformIndices, pname);

Parameters

program
A WebGLProgram containing the active uniforms.
uniformIndices
An Array of GLuint specifying the indices of the active uniforms to query.
pname
A GLenum specifying which information to query. Possible values:
  • gl.UNIFORM_TYPE: Returns an Array of GLenum indicating the types of the uniforms.
  • gl.UNIFORM_SIZE: Returns an Array of GLuint indicating the sizes of the uniforms.
  • gl.UNIFORM_BLOCK_INDEX: Returns an Array of GLint indicating the block indices of the uniforms.
  • gl.UNIFORM_OFFSET: Returns an Array of GLint indicating the uniform buffer offsets.
  • gl.UNIFORM_ARRAY_STRIDE: Returns an Array of GLint indicating the strides between the elements.
  • gl.UNIFORM_MATRIX_STRIDE: Returns an Array of GLint indicating the strides between columns of a column-major matrix or a row-major matrix.
  • gl.UNIFORM_IS_ROW_MAJOR: Returns an Array of GLboolean indicating whether each of the uniforms is a row-major matrix or not.

Return value

Depends on which information is requested using the pname parameter.

Examples

var uniformIndices = gl.getUniformIndices(program, ["UBORed", "UBOGreen", "UBOBlue"]);
var uniformOffsets = gl.getActiveUniforms(program, uniformIndices, gl.UNIFORM_OFFSET);

Specifications

Specification Status Comment
WebGL 2.0
The definition of 'getActiveUniforms' in that specification.
Editor's Draft Initial definition for WebGL.
OpenGL ES 3.0
The definition of 'glGetActiveUniformsiv' in that specification.
Standard Man page of the (similar) OpenGL API.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support [2] Nightly build [1] No support No support No support
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support No support No support No support No support No support

[1] WebGL 2 is enabled by default in Firefox Nightly. To enable it in a release version of Firefox, set the preference webgl.enable-prototype-webgl2 to true in about:config.

[2] To use an experimental implementation of WebGL 2 in Chrome, you have to start Chrome with the runtime flag --enable-unsafe-es3-apis.

See also

Document Tags and Contributors

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