void glIndexd( GLdouble c) void glIndexf( GLfloat c) void glIndexi( GLint c) void glIndexs( GLshort c) void glIndexub( GLubyte c) void glIndexdv( const GLdouble *c) void glIndexfv( const GLfloat *c) void glIndexiv( const GLint *c) void glIndexsv( const GLshort *c) void glIndexubv( const GLubyte *c)
The current index is stored as a floating-point value. Integer values are converted directly to floating-point values, with no special mapping. The initial value is 1.
Index values outside the representable range of the color index buffer are not clamped. However, before an index is dithered (if enabled) and written to the frame buffer, it is converted to fixed-point format. Any bits in the integer portion of the resulting fixed-point value that do not correspond to bits in the frame buffer are masked out.
The current index can be updated at any time. In particular, glIndex can be called between a call to glBegin and the corresponding call to glEnd.