Light | Dark



gl_FragDepth — establishes a depth value for the current fragment


out float gl_FragDepth ;


Available only in the fragment language, gl_FragDepth is an output variable that is used to establish the depth value for the current fragment. If depth buffering is enabled and no shader writes to gl_FragDepth, then the fixed function value for depth will be used (this value is contained in the z component of gl_FragCoord) otherwise, the value written to gl_FragDepth is used. If a shader statically assigns to gl_FragDepth, then the value of the fragment's depth may be undefined for executions of the shader that don't take that path. That is, if the set of linked fragment shaders statically contain a write to gl_FragDepth, then it is responsible for always writing it.

Version Support

OpenGL Shading Language Version
Variable Name 1.10 1.20 1.30 1.40 1.50 3.30 4.00 4.10 4.20 4.30 4.40 4.50

See Also


Think you can improve this page? Edit this page on GitHub.