glIndexPointer

glIndexPointer: man2/glIndexPointer.xml

glIndexPointer specifies the location and data format of an array of color indexes to use when rendering. type specifies the data type of each color index and stride specifies the byte stride from one color index to the next, allowing vertices and attributes to be packed into a single array or stored in separate arrays. If a non-zero named buffer object is bound to the GL_ARRAY_BUFFER target (see glBindBuffer ) while a color index array is specified, pointer is treated as a byte offset into the buffer object's data store. Also, the buffer object binding ( GL_ARRAY_BUFFER_BINDING ) is saved as color index vertex array client-side state ( GL_INDEX_ARRAY_BUFFER_BINDING ). When a color index array is specified, type, stride, and pointer are saved as client-side state, in addition to the current vertex array buffer object binding. To enable and disable the color index array, call glEnableClientState and glDisableClientState with the argument GL_INDEX_ARRAY. If enabled, the color index array is used when glDrawArrays, glMultiDrawArrays, glDrawElements, glMultiDrawElements, glDrawRangeElements, or glArrayElement is called.

glIndexPointer is available only if the GL version is 1.1 or greater. Color indexes are not supported for interleaved vertex array formats (see glInterleavedArrays ). The color index array is initially disabled and isn't accessed when glArrayElement, glDrawElements, glDrawRangeElements, glDrawArrays, glMultiDrawArrays, or glMultiDrawElements is called. Execution of glIndexPointer is not allowed between glBegin and the corresponding glEnd, but an error may or may not be generated. If an error is not generated, the operation is undefined. glIndexPointer is typically implemented on the client side. Color index array parameters are client-side state and are therefore not saved or restored by glPushAttrib and glPopAttrib. Use glPushClientAttrib and glPopClientAttrib instead.