WebGLShader

The WebGLShader is part of the WebGL API and can either be a vertex or a fragment shader. A WebGLProgram requires both types of shaders.

Description

To create a WebGLShader use WebGLRenderingContext.createShader, then hook up the GLSL source code using WebGLRenderingContext.shaderSource(), and finally invoke WebGLRenderingContext.compileShader() to finish and compile the shader. At this point the WebGLShader is still not in a usable form and must still be attached to a WebGLProgram.

function createShader (gl, sourceCode, type) {
  // Compiles either a shader of type gl.VERTEX_SHADER or gl.FRAGMENT_SHADER
  var shader = gl.createShader( type );
  gl.shaderSource( shader, sourceCode );
  gl.compileShader( shader );
  if ( !gl.getShaderParameter(shader, gl.COMPILE_STATUS) ) {
    var info = gl.getShaderInfoLog( shader );
    throw 'Could not compile WebGL program. \n\n' + info;
  }
  return shader;
}

See WebGLProgram for information on attaching the shaders.

Examples

Creating a vertex shader

Note that there are many other strategies for writing and accessing shader source code strings. These example are for illustration purposes only.

var vertexShaderSource =
  'attribute vec4 position;\n' +
  'void main() {\n' +
  '  gl_Position = position;\n' +
  '}\n';
//Use the createShader function from the example above
var vertexShader = createShader(gl, vertexShaderSource, gl.VERTEX_SHADER)

Creating a fragment shader

var fragmentShaderSource =
  'void main() {\n' +
  '  gl_FragColor = vec4(1.0, 1.0, 1.0, 1.0);\n' +
  '}\n';
//Use the createShader function from the example above
var fragmentShader = createShader(gl, fragmentShaderSource, gl.FRAGMENT_SHADER)

Specifications

Specification Status Comment
WebGL 1.0
The definition of 'WebGLShader' in that specification.
Recommendation Initial definition.

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support94.01211125.1
Available in workers(No)44.01(No)(No)(No)(No)
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support(Yes)25(Yes)(Yes)11128.1
Available in workers(No)(No)(No)(No)(No)(No)(No)

1. From version 44.0, this feature is behind the gfx.offscreencanvas.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

See also

Document Tags and Contributors

 Contributors to this page: fscholz, nmve, teoli, MrOpposite, zalomea, gregtatum
 Last updated by: fscholz,