Name

    SGI_swap_control

Name Strings

    GLX_SGI_swap_control

Version

    $Date: 1996/09/09 00:59:50 $ $Revision: 1.2 $

Number

    40

Dependencies

    None

Overview

    This extension allows an application to specify a minimum periodicity
    of color buffer swaps, measured in video frame periods.

New Procedures and Functions

    int glXSwapIntervalSGI(int interval)

New Tokens

    None

Additions to Chapter 2 of the 1.0 Specification (OpenGL Operation)

    None

Additions to Chapter 3 of the 1.0 Specification (Rasterization)

    None

Additions to Chapter 4 of the 1.0 Specification (Per-Fragment Operations and
the Framebuffer)

    None

Additions to Chapter 5 of the 1.0 Specification (Special Functions)

    None

Additions to Chapter 6 of the 1.0 Specification (State and State Requests)

    None

Additions to the GLX Specification

    [Add the following to Section 3.2.6 of the GLX Specification (Double
     Buffering)]

    glXSwapIntervalSGI specifies the minimum number of video frame periods
    per buffer swap.  (e.g. a value of two means that the color buffers
    will be swapped at most every other video frame.)  A return value
    of zero indicates success; otherwise an error occurred.  The interval
    takes effect when glXSwapBuffers is first called subsequent to the
    glXSwapIntervalSGI call.

    A video frame period is the time required by the monitor to display a 
    full frame of video data.  In the case of an interlaced monitor,
    this is typically the time required to display both the even and odd 
    fields of a frame of video data.

Errors

    glXSwapIntervalSGI returns GLX_BAD_VALUE if parameter < interval > is
    less than or equal to zero.

    glXSwapIntervalSGI returns GLX_BAD_CONTEXT if there is no current
    GLXContext.

New State

    None

    Get Value		Get Command	Type	    Initial Value
    ---------		-----------	----	    -------------
    [swap interval]	[none]		Z+	     
New Implementation Dependent State

    None