%mathent; ]> 2011-2014 Khronos Group gl_VertexID 3G gl_VertexID contains the index of the current vertex in highp int gl_VertexID gl_VertexID is a vertex language input variable that holds an integer index for the vertex. The index is impliclty generated by glDrawArrays and other commands that do not reference the content of the GL_ELEMENT_ARRAY_BUFFER, or explicitly generated from the content of the GL_ELEMENT_ARRAY_BUFFER by commands such as glDrawElements. gl_VertexID gl_InstanceID 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/.