GPU synchronisation fences

GPU synchronisation fences — Functions for notification of command completion

Synopsis

                    CoglFence;
void                (*CoglFenceCallback)                (CoglFence *fence,
                                                         void *user_data);
                    CoglFenceClosure;
void *              cogl_fence_closure_get_user_data    (CoglFenceClosure *closure);
CoglFenceClosure *  cogl_framebuffer_add_fence_callback (CoglFramebuffer *framebuffer,
                                                         CoglFenceCallback callback,
                                                         void *user_data);
void                cogl_framebuffer_cancel_fence_callback
                                                        (CoglFramebuffer *framebuffer,
                                                         CoglFenceClosure *closure);

Description

Cogl allows notification of GPU command completion; users may mark points in the GPU command stream and receive notification when the GPU has executed to that point.

Details

CoglFence

typedef struct _CoglFence CoglFence;

An opaque object representing a fence. This type is currently unused but in the future may be used to pass extra information about the fence completion.

Since 2.0

Stability Level: Unstable


CoglFenceCallback ()

void                (*CoglFenceCallback)                (CoglFence *fence,
                                                         void *user_data);

The callback prototype used with cogl_framebuffer_add_fence_callback() for notification of GPU command completion.

fence :

Unused. In the future this parameter may be used to pass extra information about the fence completion but for now it should be ignored.

user_data :

The private data passed to cogl_framebuffer_add_fence_callback()

Since 2.0

Stability Level: Unstable


CoglFenceClosure

typedef struct _CoglFenceClosure CoglFenceClosure;

An opaque type representing one future callback to be made when the GPU command stream has passed a certain point.

Since 2.0

Stability Level: Unstable


cogl_fence_closure_get_user_data ()

void *              cogl_fence_closure_get_user_data    (CoglFenceClosure *closure);

cogl_framebuffer_add_fence_callback ()

CoglFenceClosure *  cogl_framebuffer_add_fence_callback (CoglFramebuffer *framebuffer,
                                                         CoglFenceCallback callback,
                                                         void *user_data);

Calls the provided callback when all previously-submitted commands have been executed by the GPU.

framebuffer :

The CoglFramebuffer the commands have been submitted to

callback :

A CoglFenceCallback to be called when all commands submitted to Cogl have been executed

user_data :

Private data that will be passed to the callback

Returns :

non-NULL if the fence succeeded, or NULL if it was unable to be inserted and the callback will never be called. The user does not need to free the closure; it will be freed automatically when the callback is called, or cancelled.

Since 2.0

Stability Level: Unstable


cogl_framebuffer_cancel_fence_callback ()

void                cogl_framebuffer_cancel_fence_callback
                                                        (CoglFramebuffer *framebuffer,
                                                         CoglFenceClosure *closure);

Removes a fence previously submitted with cogl_framebuffer_add_fence_callback(); the callback will not be called.

framebuffer :

The CoglFramebuffer the commands were submitted to

closure :

The CoglFenceClosure returned from cogl_framebuffer_add_fence_callback()

Since 2.0

Stability Level: Unstable