EXT_frag_depth extension

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The EXT_frag_depth extension is part of the WebGL API and enables to set a depth value of a fragment from within the fragment shader.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

Note: This extension is only available to WebGL1 contexts. In WebGL2, the functionality of this extension is available on the WebGL2 context by default. It requires GLSL #version 300 es.

Examples

Enable the extension:

js
gl.getExtension("EXT_frag_depth");

Now the output variable gl_FragDepthEXT is available to set a depth value of a fragment from within the fragment shader:

html
<script type="x-shader/x-fragment">
  void main() {
    gl_FragColor = vec4(1.0, 0.0, 1.0, 1.0);
    gl_FragDepthEXT = 0.5;
  }
</script>

Specifications

Specification
WebGL EXT_frag_depth Khronos Ratified Extension Specification

Browser compatibility

See also