Gambas Documentation - /comp/gb.opengl/gl/indexmask

/comp/gb.opengl/gl/indexmask

# Gl.IndexMask (gb.opengl)

Static Sub IndexMask ( Mask As Integer )

Control the writing of individual bits in the color index buffers.

### Parameters

mask

  Specifies a bit mask to enable and disable the writing of individual bits in the color index buffers. Initially, the mask is all 1's.

### Description

Gl.IndexMask 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. Where a 1 (one) appears in the mask, it's possible to write to the corresponding bit in the color index buffer (or buffers). Where a 0 (zero) appears, the corresponding bit is write-protected.

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

### Errors

Gl.INVALID_OPERATION is generated if Gl.IndexMask is executed between the execution of Gl.Begin and the corresponding execution of Gl.End.

### Associated Gets

Gl.Get with argument Gl.INDEX_WRITEMASK

### See also

- Gl.ColorMask,

- Gl.DepthMask,

- Gl.DrawBuffer,

Gl.Index, Gl.IndexPointer,

- Gl.StencilMask

See original documentation on OpenGL website