2011 Khronos Group
gl_TessLevelInner 3G
gl_TessLevelInner contains the inner tessellation levels for the current patch

## Declaration

`patch out float gl_TessLevelInner[2];` (tessellation control language)
`patch in float gl_TessLevelInner[2];` (tessellation evaluation languge)

## Description

Available only in the tessellation control and evaluation languages, `gl_TessLevelInner` is used to assign values to the corresponding inner tesellation levels of the current patch. The values written into `gl_TessLevelInner` by the tessellation control shader are used by the tessellation primitive generator to control primitive tessellation and may be read by the subsequent tessellation evaluation shader.

As inputs to the tessellation evaluation shader, `gl_TessLevelInner` contains the values written by the tessellation control shader, if present. If no tessellation control shader is present, it contains the default tessellation level.

## Version Support

Variable | Version 1.10 | Version 1.20 | Version 1.30 | Version 1.40 | Version 1.50 | Version 3.30 | Version 4.00 | Version 4.10
--- | --- | --- | --- | --- | --- | --- | --- | ---
gl_TessLevelInner | - | - | - | - | - | - | Y | Y

## See Also

gl_TessLevelOuter, gl_TessCoord

## Copyright

Copyright 2011 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.