glClearIndex
The glClearIndex function specifies the clear value for the color-index buffers.
void glClearIndex(
GLfloat c);
Parameters
- c
The index used when the color-index buffers are cleared. The default value is zero.
Remarks
The glClearIndex function specifies the index used by glClear to clear the color-index buffers. The c parameter is not clamped. Rather, c is converted to a fixed-point value with unspecified precision to the right of the binary point. The integer part of this value is then masked with 2*m* 1, where m is the number of bits in a color index stored in the framebuffer.
The following functions retrieve information related to glClearIndex:
glGet with argument GL_INDEX_CLEAR_VALUE
glGet with argument GL_INDEX_BITS
Error Codes
The following is the error code generated and its condition.
| Error code | Condition |
|---|---|
| GL_INVALID_OPERATION | glClearIndex 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.