def _newAxes(self):
"""Given self._rotation and self._swapped, calculates and sets
the appropriate data2scene transformation.
"""
# TODO: this function works, but it is not elegant. There must
# be a simpler way to calculate the appropriate tranformation.
w, h = self.dataShape
assert self._rotation in range(0, 4)
# unlike self._rotation, the local variable 'rotation'
# indicates how many times to rotate clockwise after swapping
# axes.
# t1 : do axis swap
t1 = QTransform()
if self._swapped:
t1 = QTransform(0, 1, 0, 1, 0, 0, 0, 0, 1)
h, w = w, h
# t2 : do rotation
t2 = QTransform()
t2.rotate(self._rotation * 90)
# t3: shift to re-center
rot2trans = {0: (0, 0), 1: (h, 0), 2: (w, h), 3: (0, w)}
trans = rot2trans[self._rotation]
t3 = QTransform.fromTranslate(*trans)
self.data2scene = t1 * t2 * t3
if self._tileProvider:
self._tileProvider.axesSwapped = self._swapped
self.axesChanged.emit(self._rotation, self._swapped)
def _fetch_tile_layer(self, timestamp, ims, transform, tile_nr, stack_id, ims_req, cache):
"""
Fetch a single tile from a layer (ImageSource).
Parameters
----------
timestamp
The timestamp at which ims_req was created
ims
The layer (image source) we're fetching from
transform
The transform to apply to the fetched data, before storing it in the cache
tile_nr
The ID of the fetched tile
stack_id
The stack ID of the tile we're fetching (e.g. which T-slice and Z-slice this tile belongs to)
ims_req
A request object (e.g. GrayscaleImageRequest) with a wait() method that produces an item of
the appropriate type for the layer (i.e. either a QImage or a QGraphicsItem)
cache
The value of self._cache at the time the ims_req was created.
(The cache can be replaced occasionally. See TileProvider._onSizeChanged().)
"""
try:
try:
with cache:
layerTimestamp = cache.layerTimestamp(stack_id, ims, tile_nr)
except KeyError:
# May not be a timestamp yet (especially when prefetching)
layerTimestamp = 0
tile_rect = QRectF( self.tiling.imageRects[tile_nr] )
if timestamp > layerTimestamp:
img = ims_req.wait()
if isinstance(img, QImage):
img = img.transformed(transform)
elif isinstance(img, QGraphicsItem):
# FIXME: It *seems* like applying the same transform to QImages and QGraphicsItems
# makes sense here, but for some strange reason it isn't right.
# For QGraphicsItems, it seems obvious that this is the correct transform.
# I do not understand the formula that produces 'transform', which is used for QImage tiles.
img.setTransform(QTransform.fromTranslate(tile_rect.left(), tile_rect.top()), combine=True)
img.setTransform(self.tiling.data2scene, combine=True)
else:
assert False, "Unexpected image type: {}".format( type(img) )
with cache:
try:
cache.updateTileIfNecessary(stack_id, ims, tile_nr, timestamp, img)
except KeyError:
pass
if stack_id == self._current_stack_id \
and cache is self._cache:
self.sceneRectChanged.emit( tile_rect )
except BaseException:
sys.excepthook( *sys.exc_info() )
def _fetch_tile_layer(self, timestamp, ims, transform, tile_nr, stack_id, ims_req, cache):
"""
Fetch a single tile from a layer (ImageSource).
Parameters
----------
timestamp
The timestamp at which ims_req was created
ims
The layer (image source) we're fetching from
transform
The transform to apply to the fetched data, before storing it in the cache
tile_nr
The ID of the fetched tile
stack_id
The stack ID of the tile we're fetching (e.g. which T-slice and Z-slice this tile belongs to)
ims_req
A request object (e.g. GrayscaleImageRequest) with a wait() method that produces an item of
the appropriate type for the layer (i.e. either a QImage or a QGraphicsItem)
cache
The value of self._cache at the time the ims_req was created.
(The cache can be replaced occasionally. See TileProvider._onSizeChanged().)
"""
try:
try:
with cache:
layerTimestamp = cache.layerTimestamp(stack_id, ims, tile_nr)
except KeyError:
# May not be a timestamp yet (especially when prefetching)
layerTimestamp = 0
tile_rect = QRectF( self.tiling.imageRects[tile_nr] )
if timestamp > layerTimestamp:
img = ims_req.wait()
if isinstance(img, QImage):
img = img.transformed(transform)
elif isinstance(img, QGraphicsItem):
# FIXME: It *seems* like applying the same transform to QImages and QGraphicsItems
# makes sense here, but for some strange reason it isn't right.
# For QGraphicsItems, it seems obvious that this is the correct transform.
# I do not understand the formula that produces 'transform', which is used for QImage tiles.
img.setTransform(QTransform.fromTranslate(tile_rect.left(), tile_rect.top()), combine=True)
img.setTransform(self.tiling.data2scene, combine=True)
else:
assert False, "Unexpected image type: {}".format( type(img) )
with cache:
try:
cache.updateTileIfNecessary(stack_id, ims, tile_nr, timestamp, img)
except KeyError:
pass
if stack_id == self._current_stack_id \
and cache is self._cache:
self.sceneRectChanged.emit( tile_rect )
except BaseException:
sys.excepthook( *sys.exc_info() )
def _newAxes(self):
"""Given self._rotation and self._swapped, calculates and sets
the appropriate data2scene transformation.
"""
# TODO: this function works, but it is not elegant. There must
# be a simpler way to calculate the appropriate transformation.
w, h = self.dataShape
assert self._rotation in range(0, 4)
# unlike self._rotation, the local variable 'rotation'
# indicates how many times to rotate clockwise after swapping
# axes.
# t1 : do axis swap
t1 = QTransform()
if self._swapped:
t1 = QTransform(0, 1, 0,
1, 0, 0,
0, 0, 1)
h, w = w, h
# t2 : do rotation
t2 = QTransform()
t2.rotate(self._rotation * 90)
# t3: shift to re-center
rot2trans = {0 : (0, 0),
1 : (h, 0),
2 : (w, h),
3 : (0, w)}
trans = rot2trans[self._rotation]
t3 = QTransform.fromTranslate(*trans)
self.data2scene = t1 * t2 * t3
if self._tileProvider:
self._tileProvider.axesSwapped = self._swapped
self.axesChanged.emit(self._rotation, self._swapped)