glIndexMask

  • Article

The glIndexMask function controls the writing of individual bits in the color-index buffers.

void glIndexMask(
  GLuint mask);

Parameters

  • mask
    A bit mask to enable and disable the writing of individual bits in the color-index buffers. Initially, the mask is all ones.

Remarks

The glIndexMask function controls the writing of individual bits in the color-index buffers. The least significant n bits of mask, where n is the number of bits in a color-index buffer, specify a mask. Wherever a one appears in the mask, the corresponding bit in the color-index buffer (or buffers) is made writable. Where a zero appears, the bit is write-protected.

This mask is used only in color-index mode, and it affects only the buffers currently selected for writing (see glDrawBuffer). Initially, all bits are enabled for writing.

The following function retrieves information related to glIndexMask:

glGet with argument GL_INDEX_WRITEMASK

Error Codes

The following is the error code and its condition.

Error code Condition
GL_INVALID_OPERATION glIndexMask was called between a call to glBegin and the corresponding call to glEnd.

Requirements

**  Windows NT/2000:** Requires Windows NT 3.5 or later.
**  Windows 95/98:** Requires Windows 95 or later. Available as a redistributable for Windows 95.
**  Header:** Declared in Gl.h.
**  Library:** Use Opengl32.lib.

See Also

glBegin, glDepthMask, glDrawBuffer, glEnd, glIndex, glStencilMask