/**
* _cairo_surface_snapshot:
* @surface: a #cairo_surface_t
*
* Make an immutable reference to @surface. It is an error to call a
* surface-modifying function on the result of this function. The
* resulting 'snapshot' is a lazily copied-on-write surface i.e. it
* remains a reference to the original surface until that surface is
* written to again, at which time a copy is made of the original surface
* and the snapshot then points to that instead. Multiple snapshots of the
* same unmodified surface point to the same copy.
*
* The caller owns the return value and should call
* cairo_surface_destroy() when finished with it. This function will not
* return %NULL, but will return a nil surface instead.
*
* Return value: The snapshot surface. Note that the return surface
* may not necessarily be of the same type as @surface.
**/
cairo_surface_t *
_cairo_surface_snapshot (cairo_surface_t *surface)
{
cairo_surface_snapshot_t *snapshot;
cairo_status_t status;
TRACE ((stderr, "%s: target=%d\n", __FUNCTION__, surface->unique_id));
if (unlikely (surface->status))
return _cairo_surface_create_in_error (surface->status);
if (unlikely (surface->finished))
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_FINISHED));
if (surface->snapshot_of != NULL)
return cairo_surface_reference (surface);
if (_cairo_surface_is_snapshot (surface))
return cairo_surface_reference (surface);
snapshot = (cairo_surface_snapshot_t *)
_cairo_surface_has_snapshot (surface, &_cairo_surface_snapshot_backend);
if (snapshot != NULL)
return cairo_surface_reference (&snapshot->base);
snapshot = malloc (sizeof (cairo_surface_snapshot_t));
if (unlikely (snapshot == NULL))
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_FINISHED));
_cairo_surface_init (&snapshot->base,
&_cairo_surface_snapshot_backend,
NULL, /* device */
surface->content);
snapshot->base.type = surface->type;
CAIRO_MUTEX_INIT (snapshot->mutex);
snapshot->target = surface;
snapshot->clone = NULL;
status = _cairo_surface_copy_mime_data (&snapshot->base, surface);
if (unlikely (status)) {
cairo_surface_destroy (&snapshot->base);
return _cairo_surface_create_in_error (status);
}
snapshot->base.device_transform = surface->device_transform;
snapshot->base.device_transform_inverse = surface->device_transform_inverse;
_cairo_surface_attach_snapshot (surface,
&snapshot->base,
_cairo_surface_snapshot_copy_on_write);
return &snapshot->base;
}
cairo_image_transparency_t
_cairo_image_analyze_transparency (cairo_image_surface_t *image)
{
if (_cairo_surface_is_snapshot (&image->base)) {
if (image->transparency == CAIRO_IMAGE_UNKNOWN)
image->transparency = _cairo_image_compute_transparency (image);
return image->transparency;
}
return _cairo_image_compute_transparency (image);
}
static cairo_int_status_t
_analyze_recording_surface_pattern (cairo_analysis_surface_t *surface,
const cairo_pattern_t *pattern)
{
const cairo_surface_pattern_t *surface_pattern;
cairo_analysis_surface_t *tmp;
cairo_surface_t *source, *proxy;
cairo_matrix_t p2d;
cairo_status_t status, analysis_status;
assert (pattern->type == CAIRO_PATTERN_TYPE_SURFACE);
surface_pattern = (const cairo_surface_pattern_t *) pattern;
assert (surface_pattern->surface->type == CAIRO_SURFACE_TYPE_RECORDING);
source = surface_pattern->surface;
proxy = _cairo_surface_has_snapshot (source, &proxy_backend);
if (proxy != NULL) {
/* nothing untoward found so far */
return CAIRO_STATUS_SUCCESS;
}
tmp = (cairo_analysis_surface_t *)
_cairo_analysis_surface_create (surface->target);
if (unlikely (tmp->base.status))
return tmp->base.status;
proxy = attach_proxy (source, &tmp->base);
p2d = pattern->matrix;
status = cairo_matrix_invert (&p2d);
assert (status == CAIRO_STATUS_SUCCESS);
cairo_matrix_multiply (&tmp->ctm, &p2d, &surface->ctm);
tmp->has_ctm = ! _cairo_matrix_is_identity (&tmp->ctm);
if (_cairo_surface_is_snapshot (source))
source = _cairo_surface_snapshot_get_target (source);
if (_cairo_surface_is_subsurface (source))
source = _cairo_surface_subsurface_get_target (source);
status = _cairo_recording_surface_replay_and_create_regions (source,
&tmp->base);
analysis_status = tmp->has_unsupported ? CAIRO_INT_STATUS_IMAGE_FALLBACK : CAIRO_INT_STATUS_SUCCESS;
detach_proxy (proxy);
cairo_surface_destroy (&tmp->base);
if (unlikely (status))
return status;
return analysis_status;
}
static cairo_surface_t *
unwrap_surface (const cairo_pattern_t *pattern)
{
cairo_surface_t *surface;
surface = ((const cairo_surface_pattern_t *) pattern)->surface;
if (_cairo_surface_is_paginated (surface))
surface = _cairo_paginated_surface_get_recording (surface);
if (_cairo_surface_is_snapshot (surface))
surface = _cairo_surface_snapshot_get_target (surface);
if (_cairo_surface_is_observer (surface))
surface = _cairo_surface_observer_get_target (surface);
return surface;
}
static void
_cairo_surface_snapshot_copy_on_write (cairo_surface_t *surface)
{
cairo_surface_snapshot_t *snapshot = (cairo_surface_snapshot_t *) surface;
cairo_image_surface_t *image;
cairo_surface_t *clone;
void *extra;
cairo_status_t status;
TRACE ((stderr, "%s: target=%d\n",
__FUNCTION__, snapshot->target->unique_id));
/* We need to make an image copy of the original surface since the
* snapshot may exceed the lifetime of the original device, i.e.
* when we later need to use the snapshot the data may have already
* been lost.
*/
CAIRO_MUTEX_LOCK (snapshot->mutex);
if (snapshot->target->backend->snapshot != NULL) {
clone = snapshot->target->backend->snapshot (snapshot->target);
if (clone != NULL) {
assert (clone->status || ! _cairo_surface_is_snapshot (clone));
goto done;
}
}
/* XXX copy to a similar surface, leave acquisition till later?
* We should probably leave such decisions to the backend in case we
* rely upon devices/connections like Xlib.
*/
status = _cairo_surface_acquire_source_image (snapshot->target, &image, &extra);
if (unlikely (status)) {
snapshot->target = _cairo_surface_create_in_error (status);
status = _cairo_surface_set_error (surface, status);
goto unlock;
}
clone = image->base.backend->snapshot (&image->base);
_cairo_surface_release_source_image (snapshot->target, image, extra);
done:
status = _cairo_surface_set_error (surface, clone->status);
snapshot->target = snapshot->clone = clone;
snapshot->base.type = clone->type;
unlock:
CAIRO_MUTEX_UNLOCK (snapshot->mutex);
}
static cairo_int_status_t
_cairo_analysis_surface_mask (void *abstract_surface,
cairo_operator_t op,
const cairo_pattern_t *source,
const cairo_pattern_t *mask,
const cairo_clip_t *clip)
{
cairo_analysis_surface_t *surface = abstract_surface;
cairo_int_status_t backend_status;
cairo_rectangle_int_t extents;
if (surface->target->backend->mask == NULL) {
backend_status = CAIRO_INT_STATUS_UNSUPPORTED;
} else {
backend_status =
surface->target->backend->mask (surface->target,
op, source, mask, clip);
if (_cairo_int_status_is_error (backend_status))
return backend_status;
}
if (backend_status == CAIRO_INT_STATUS_ANALYZE_RECORDING_SURFACE_PATTERN) {
cairo_int_status_t backend_source_status = CAIRO_STATUS_SUCCESS;
cairo_int_status_t backend_mask_status = CAIRO_STATUS_SUCCESS;
if (source->type == CAIRO_PATTERN_TYPE_SURFACE) {
cairo_surface_t *src_surface = ((cairo_surface_pattern_t *)source)->surface;
if (_cairo_surface_is_snapshot (src_surface))
src_surface = _cairo_surface_snapshot_get_target (src_surface);
if (_cairo_surface_is_recording (src_surface)) {
backend_source_status =
_analyze_recording_surface_pattern (surface, source);
if (_cairo_int_status_is_error (backend_source_status))
return backend_source_status;
}
}
if (mask->type == CAIRO_PATTERN_TYPE_SURFACE) {
cairo_surface_t *mask_surface = ((cairo_surface_pattern_t *)mask)->surface;
if (_cairo_surface_is_snapshot (mask_surface))
mask_surface = _cairo_surface_snapshot_get_target (mask_surface);
if (_cairo_surface_is_recording (mask_surface)) {
backend_mask_status =
_analyze_recording_surface_pattern (surface, mask);
if (_cairo_int_status_is_error (backend_mask_status))
return backend_mask_status;
}
}
backend_status =
_cairo_analysis_surface_merge_status (backend_source_status,
backend_mask_status);
}
_cairo_analysis_surface_operation_extents (surface,
op, source, clip,
&extents);
if (_cairo_operator_bounded_by_mask (op)) {
cairo_rectangle_int_t mask_extents;
_cairo_pattern_get_extents (mask, &mask_extents);
_cairo_rectangle_intersect (&extents, &mask_extents);
}
return _add_operation (surface, &extents, backend_status);
}
