The WebGLRenderingContext.getUniform() method of the WebGL API returns the value of a uniform variable at a given location.
Syntax
any gl.getUniform(program, location);
Parameters
- program
- A
WebGLProgramcontaining the uniform attribute. - location
- A
WebGLUniformLocationobject containing the location of the uniform attribute to get.
Return value
The returned type depends on the uniform type:
| Uniform type | Returned type |
|---|---|
| WebGL 1 only | |
boolean |
GLBoolean |
int |
GLint |
float |
GLfloat |
vec2 |
Float32Array (with 2 elements) |
ivec2 |
Int32Array (with 2 elements) |
bvec2 |
Array of GLBoolean (with 2 elements) |
vec3 |
Float32Array (with 3 elements) |
ivec3 |
Int32Array (with 3 elements) |
bvec3 |
Array of GLBoolean (with 3 elements) |
vec4 |
Float32Array (with 4 elements) |
ivec4 |
Int32Array (with 4 elements) |
bvec4 |
Array of GLBoolean (with 4 elements) |
mat2 |
Float32Array (with 4 elements) |
mat3 |
Float32Array (with 9 elements) |
mat4 |
Float32Array (with 16 elements) |
sampler2D |
GLint |
samplerCube |
GLint |
| Additionally available in WebGL 2 | |
uint |
GLuint |
uvec2 |
Uint32Array (with 2 elements) |
uvec3 |
Uint32Array (with 3 elements) |
uvec4 |
Uint32Array (with 4 elements) |
mat2x3 |
Float32Array (with 6 elements) |
mat2x4 |
Float32Array (with 8 elements) |
mat3x2 |
Float32Array (with 6 elements) |
mat3x4 |
Float32Array (with 12 elements) |
mat4x2 |
Float32Array (with 8 elements) |
mat4x3 |
Float32Array (with 12 elements) |
| any sampler type | GLint |
Examples
var loc = gl.getUniformLocation(program, "u_foobar"); gl.getUniform(program, loc);
Specifications
| Specification | Status | Comment |
|---|---|---|
| WebGL 1.0 The definition of 'getUniform' in that specification. |
Recommendation | Initial definition for WebGL. |
| OpenGL ES 2.0 The definition of 'glGetUniform' in that specification. |
Standard | Man page of the (similar) OpenGL ES 2 API. |
| WebGL 2.0 The definition of 'getUniform' in that specification. |
Editor's Draft | Updated definition for WebGL. |
| OpenGL ES 3.0 The definition of 'glGetUniform' in that specification. |
Standard | Man page of the (similar) OpenGL ES 3 API. |
Browser compatibility
| Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | 9 | 12 | 4.0 (2.0) | 11 | 12 | 5.1 |
| WebGL 2 | No support [2] | No support | Nightly build [1] | No support | No support | No support |
| Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|
| Basic support | ? | 25 | 4.0 (2.0) | 1.0 | ? | 12 | 8.0 |
| WebGL 2 | No 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.