Package org.lwjgl.opengl

Class ARBSync

java.lang.Object

org.lwjgl.opengl.ARBSync

public class ARBSync
extends java.lang.Object

Native bindings to the ARB_sync extension.

This extension introduces the concept of "sync objects". Sync objects are a synchronization primitive - a representation of events whose completion status can be tested or waited upon. One specific type of sync object, the "fence sync object", is supported in this extension, and additional types can easily be added in the future.

Fence sync objects have corresponding fences, which are inserted into the OpenGL command stream at the time the sync object is created. A sync object can be queried for a given condition. The only condition supported for fence sync objects is completion of the corresponding fence command. Fence completion allows applications to request a partial Finish, wherein all commands prior to the fence will be forced to complete before control is returned to the calling process.

These new mechanisms allow for synchronization between the host CPU and the GPU, which may be accessing the same resources (typically memory), as well as between multiple GL contexts bound to multiple threads in the host CPU.

Requires OpenGL 3.1. Promoted to core in OpenGL 3.2.

Field Summary

Fields

Modifier and Type	Field and Description
static int	GL_ALREADY_SIGNALED GL_CONDITION_SATISFIED Returned by ClientWaitSync.
static int	GL_MAX_SERVER_WAIT_TIMEOUT Accepted as the pname parameter of GetInteger64v.
static int	GL_OBJECT_TYPE Accepted as the pname parameter of GetSynciv.
static int	GL_SIGNALED Returned in values for GetSynciv pname SYNC_STATUS.
static int	GL_SYNC_CONDITION Accepted as the pname parameter of GetSynciv.
static int	GL_SYNC_FENCE Returned in values for GetSynciv pname OBJECT_TYPE.
static int	GL_SYNC_FLAGS Accepted as the pname parameter of GetSynciv.
static int	GL_SYNC_FLUSH_COMMANDS_BIT Accepted in the flags parameter of ClientWaitSync.
static int	GL_SYNC_GPU_COMMANDS_COMPLETE Returned in values for GetSynciv pname SYNC_CONDITION.
static int	GL_SYNC_STATUS Accepted as the pname parameter of GetSynciv.
static int	GL_TIMEOUT_EXPIRED Returned by ClientWaitSync.
static long	GL_TIMEOUT_IGNORED Accepted in the timeout parameter of WaitSync.
static int	GL_UNSIGNALED Returned in values for GetSynciv pname SYNC_STATUS.
static int	GL_WAIT_FAILED Returned by ClientWaitSync.

Method Summary

Modifier and Type	Method and Description
static int	glClientWaitSync(long sync, int flags, long timeout) Causes the client to block and wait for a sync object to become signaled.
static void	glDeleteSync(long sync) Deletes a sync object.
static long	glFenceSync(int condition, int flags) Creates a new sync object and inserts it into the GL command stream.
static long	glGetInteger64(int pname) Returns the 64bit integer value or values of a selected parameter.
static void	glGetInteger64v(int pname, long[] params) Array version of: GetInteger64v
static void	glGetInteger64v(int pname, java.nio.LongBuffer params) Returns the 64bit integer value or values of a selected parameter.
static int	glGetSynci(long sync, int pname, java.nio.IntBuffer length) Queries the properties of a sync object.
static void	glGetSynciv(long sync, int pname, int[] length, int[] values) Array version of: GetSynciv
static void	glGetSynciv(long sync, int pname, java.nio.IntBuffer length, java.nio.IntBuffer values) Queries the properties of a sync object.
static boolean	glIsSync(long sync) Determines if a name corresponds to a sync object.
static void	glWaitSync(long sync, int flags, long timeout) Causes the GL server to block and wait for a sync object to become signaled.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

GL_MAX_SERVER_WAIT_TIMEOUT

Accepted as the pname parameter of GetInteger64v.

GL_OBJECT_TYPE, GL_SYNC_CONDITION, GL_SYNC_STATUS, GL_SYNC_FLAGS

Accepted as the pname parameter of GetSynciv.

GL_SYNC_FENCE

Returned in values for GetSynciv pname OBJECT_TYPE.

GL_SYNC_GPU_COMMANDS_COMPLETE

Returned in values for GetSynciv pname SYNC_CONDITION.

GL_UNSIGNALED, GL_SIGNALED

Returned in values for GetSynciv pname SYNC_STATUS.

GL_SYNC_FLUSH_COMMANDS_BIT

Accepted in the flags parameter of ClientWaitSync.

GL_TIMEOUT_IGNORED

Accepted in the timeout parameter of WaitSync.

GL_ALREADY_SIGNALED, GL_TIMEOUT_EXPIRED, GL_CONDITION_SATISFIED, GL_WAIT_FAILED

Returned by ClientWaitSync.

Method Detail

glFenceSync

public static long glFenceSync(int condition,
                               int flags)

Creates a new sync object and inserts it into the GL command stream.

Parameters:

condition - the condition that must be met to set the sync object's state to signaled. Must be:

SYNC_GPU_COMMANDS_COMPLETE

flags - a bitwise combination of flags controlling the behavior of the sync object. No flags are presently defined for this operation and flags must be zero.

glIsSync

public static boolean glIsSync(long sync)

Determines if a name corresponds to a sync object.

Parameters:

sync - a value that may be the name of a sync object

glDeleteSync

public static void glDeleteSync(long sync)

Deletes a sync object.

Parameters:

sync - the sync object to be deleted

glClientWaitSync

public static int glClientWaitSync(long sync,
                                   int flags,
                                   long timeout)

Causes the client to block and wait for a sync object to become signaled. If sync is signaled when glClientWaitSync is called, glClientWaitSync returns immediately, otherwise it will block and wait for up to timeout nanoseconds for sync to become signaled.

The return value is one of four status values:

• ALREADY_SIGNALED indicates that sync was signaled at the time that glClientWaitSync was called.
• TIMEOUT_EXPIRED indicates that at least timeout nanoseconds passed and sync did not become signaled.
• CONDITION_SATISFIED indicates that sync was signaled before the timeout expired.
• WAIT_FAILED indicates that an error occurred. Additionally, an OpenGL error will be generated.

Parameters:

sync - the sync object whose status to wait on

flags - a bitfield controlling the command flushing behavior. One or more of:

0	SYNC_FLUSH_COMMANDS_BIT

timeout - the timeout, specified in nanoseconds, for which the implementation should wait for sync to become signaled

glWaitSync

public static void glWaitSync(long sync,
                              int flags,
                              long timeout)

Causes the GL server to block and wait for a sync object to become signaled.

glWaitSync will always wait no longer than an implementation-dependent timeout. The duration of this timeout in nanoseconds may be queried by with MAX_SERVER_WAIT_TIMEOUT. There is currently no way to determine whether glWaitSync unblocked because the timeout expired or because the sync object being waited on was signaled.

If an error occurs, glWaitSync does not cause the GL server to block.

Parameters:

sync - the sync object whose status to wait on

flags - a bitfield controlling the command flushing behavior. Must be:

0

timeout - the timeout that the server should wait before continuing. Must be:

TIMEOUT_IGNORED

glGetInteger64v

public static void glGetInteger64v(int pname,
                                   java.nio.LongBuffer params)

Returns the 64bit integer value or values of a selected parameter.

Parameters:

pname - the parameter value to be returned

params - the value or values of the specified parameter

glGetInteger64

public static long glGetInteger64(int pname)

Returns the 64bit integer value or values of a selected parameter.

Parameters:

pname - the parameter value to be returned

glGetSynciv

public static void glGetSynciv(long sync,
                               int pname,
                               java.nio.IntBuffer length,
                               java.nio.IntBuffer values)

Queries the properties of a sync object.

Parameters:

sync - the sync object whose properties to query

pname - the parameter whose value to retrieve from the sync object specified in sync. One of:

OBJECT_TYPE

SYNC_CONDITION

SYNC_STATUS

SYNC_FLAGS

length - the address of an variable to receive the number of integers placed in values

values - the address of an array to receive the values of the queried parameter

glGetSynci

public static int glGetSynci(long sync,
                             int pname,
                             java.nio.IntBuffer length)

Queries the properties of a sync object.

Parameters:

sync - the sync object whose properties to query

pname - the parameter whose value to retrieve from the sync object specified in sync. One of:

OBJECT_TYPE

SYNC_CONDITION

SYNC_STATUS

SYNC_FLAGS

length - the address of an variable to receive the number of integers placed in values

glGetInteger64v

public static void glGetInteger64v(int pname,
                                   long[] params)

Array version of: GetInteger64v

glGetSynciv

public static void glGetSynciv(long sync,
                               int pname,
                               int[] length,
                               int[] values)

Array version of: GetSynciv