gl_PointCoord - OpenGL 4 Reference Pages

## Name

gl_PointCoord — contains the coordinate of a fragment within a point

## Declaration

`in vec2 gl_PointCoord ;`

## Description

`gl_PointCoord` is a fragment language input variable that contains the two-dimensional coordinates indicating where within a point primitive the current fragment is located. If the current primitive is not a point, then values read from `gl_PointCoord` are undefined.

`gl_PointCoord.s` ranges from 0.0 to 1.0 across the point horizontally from left to right. If `GL_POINT_SPRITE_COORD_ORIGIN` is `GL_LOWER_LEFT`, `gl_PointCoord.t` varies from 0.0 to 1.0 vertically from bottom to top. Otherwise, if `GL_POINT_SPRITE_COORD_ORIGIN` is `GL_UPPER_LEFT` then `gl_PointCoord.t` varies from 0.0 to 1.0 vertically from top to bottom. The default value of `GL_POINT_SPRITE_COORD_ORIGIN` is `GL_UPPER_LEFT`.

## 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
gl_PointCoord | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔

## See Also

gl_FragCoord, gl_FragDepth

## Copyright

Copyright © 2011-2014 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/.