def __init__(self, document, page_number, bg_source=None):
QtGui.QGraphicsItem.__init__(self, None, document.scene())
self.document = document
self.bg_source = bg_source
self.bg_graphics_item = None
self.page_number = page_number
self._bounding = None
self.control_panel = PageControl(self)
self.loader = None
self.background_is_dirty = True
self.update_bounding_rect()
# This needs to be done here because a QPaintDevice needs to be initialized.
# TODO: Do this somewhere else...
if DocumentPage.placeholder_pixmap is None:
DocumentPage.placeholder_pixmap = QtGui.QPixmap()
class DocumentPage(QtGui.QGraphicsItem):
"""
A page of a PynalDocument. Can have a background (like a
page from a pdf) and contain QGraphicItems drawn by the user.
Size is either specified by the size of the background image
or the preceding image.
Attributes:
document -- The PynalDocument that contains this page.
bg_source -- The source from which the background is created.
Can be the poppler document page that is to be
rendered.
Reference kept to quickly exchange the pixmap for a new one.
_bounding -- The boundingRect of this page. Usually specified
by the background_source.
Marked private to underline that access to this should always
go over boundingRect().
page_number -- The number of this page. Counting starts at 0
and is equal to this page's position in the
document's page list.
loader -- The background generating thread of this page.
This is checked to be not None to prevent
the start of another thread to render the bg
which will result in a crash.
bg_graphics_item -- The QGraphicsItem that contains the background pixmap.
background_is_dirty -- Flag indicates that the background needs to
be re-rendered because the user zoomed or
something else made it unneeded.
"""
TYPE_DOCUMENT_PAGE = 65536
"""
This is an empty pixmap that is used by the pages when the pixmap
needs to be replaced.
"""
placeholder_pixmap = None
def __init__(self, document, page_number, bg_source=None):
QtGui.QGraphicsItem.__init__(self, None, document.scene())
self.document = document
self.bg_source = bg_source
self.bg_graphics_item = None
self.page_number = page_number
self._bounding = None
self.control_panel = PageControl(self)
self.loader = None
self.background_is_dirty = True
self.update_bounding_rect()
# This needs to be done here because a QPaintDevice needs to be initialized.
# TODO: Do this somewhere else...
if DocumentPage.placeholder_pixmap is None:
DocumentPage.placeholder_pixmap = QtGui.QPixmap()
def prevpage(self):
"""
Return the previous page, or None when there is none.
"""
try:
return self.document.pages[self.page_number -1]
except IndexError:
return None
def update_bounding_rect(self):
"""
Update the bounding rect of this page.
"""
size = self.bounding_size()
topleft = self.bounding_topleft(size)
"""
Find the scaling factor needed to transform
the page to the needed size.
Then scale, to transform all children so they stay
where they are relative to the page.
"""
newwidth = size.width()
oldwidth = self.sceneBoundingRect().width()
scale = newwidth / oldwidth
self.scale(scale, scale)
self.prepareGeometryChange()
self._bounding.setSize(QtCore.QSizeF(size))
self.setPos(topleft)
self.control_panel.update_bounding_rect()
if self.bg_graphics_item is not None:
p = self.bg_graphics_item.pixmap()
if p.isNull:
return
self.bg_graphics_item.setPixmap(p.scaled(size.toSize()))
self.background_is_dirty = True
def bounding_topleft(self, size=None):
"""
Calculate the position of the page.
Parameters:
size -- The size is needed to center the page within the scene.
When None, the size is calculated with self.bounding_size().
"""
if size is None:
size = self.bounding_size()
if self.page_number == 0:
top = 0
else:
space = Config.min_space_between_pages * self.document.scale_level
## Make enough Space for the page control of the previous page.
space += self.prevpage().control_panel.sizeF().height()
top = self.prevpage().sceneBoundingRect().bottom() + space
## Move to the left by half width so center is on y-axis of scene.
left_pos = -size.width() / 2
return QtCore.QPointF(left_pos, top)
def type(self):
return DocumentPage.TYPE_DOCUMENT_PAGE
def scale(self, x, y):
"""
Reimplementation to prevent the background pixmaps and page controls
from getting scaled. Scaling these Objects will result in an off
scale value which will distort the re-rendered pdf pages.
These must always be kept at a 1.0 scale.
Detection for these is a zValue check, as these have a value <= 0.
"""
for item in self.childItems():
if item.zValue() > 0:
item.scale(x, y)
def boundingRect(self):
"""
Return the bounding box of the page.
"""
if self._bounding is None:
self._bounding = QtCore.QRectF(0, 0, 1, 1)
self._bounding.setSize(self.bounding_size())
return self._bounding
def bounding_size(self):
"""
Calculate the size of the page by using the dimensions of the
background source.
"""
bg_size = self.bg_source.sizeF()
## Scale the background according to the documents scale level.
size = QtCore.QSizeF(math.ceil(bg_size.width() * self.document.scale_level),
math.ceil(bg_size.height() * self.document.scale_level))
return size
def paint(self, painter, option, widget=None):
"""
Nothing to paint as all paintables are children of this item.
This method is used as the notification to start rendering this
page's background and pre-caching following/previous pages.
"""
if not self.bg_source.ready_to_render():
return
if self.background_is_dirty:
self.bg_source.get_image(self.document.scale_level, self.background_ready)
self.background_is_dirty = False
#TODO: call paint on previous/next page to pre-cache.
pass
else:
pass
def background_ready(self, result):
"""
Callback method for the bg_source to bring the rendered background to.
Creates/Uses the given pixmap as a new background for this page.
TODO: send the image or a notification to the document to act as a
central cache store that removes rendered pages at a certain threshold.
Parameters:
result -- QImage or QPixmap.
"""
"""
When the rendered result does not fit (nearly) exactly in the current
bounding box, it was an older job that finished. We need a new
background.
When the pixmap does get replaced with an unfit one, it creates a
flickering of weird sized pages in the document.
"""
if math.fabs(result.size().width() - self.boundingRect().size().width()) < 2 :
self.background_is_dirty = False
else:
# Image does not fit. Don't replace the background pixmap.
if self.isVisible():
self.update() # To force a new call to paint().
return
# Replace the new_pixmap of the background with the new one.
if type(result) is QtGui.QImage:
new_pixmap = QtGui.QPixmap.fromImage(result)
else:
new_pixmap = result
# Tell the pixmap cache that a new background is in use.
self.document.cache.addBackground(self, new_pixmap)
if self.bg_graphics_item is None:
self.bg_graphics_item = QtGui.QGraphicsPixmapItem(new_pixmap, self)
else:
self.bg_graphics_item.setPixmap(new_pixmap)
self.bg_graphics_item.setZValue(Config.background_z_value)
def append(self):
""" Append a new page after this. """
self.document.insert_new_page_after(self.page_number, self.bg_source)
def move_down(self):
"""
Move this page below the page after this.
"""
if self.page_number == len(self.document.pages) - 1:
return
self.document.switch_pages(self.page_number, self.page_number + 1)
def move_up(self):
""" Move this page on top of the one over this. """
if self.page_number == 0:
return
self.document.switch_pages(self.page_number, self.page_number - 1)
def remove(self):
""" Remove this page. """
self.document.remove_page(self.page_number)
def duplicate(self):
""" Insert a duplicate of this page below it. """
pass
def clear_bg_pixmap(self):
"""
Remove the current pixmap of the background with an empty one.
The pixmap is rendered again when needed.
"""
self.bg_graphics_item.setPixmap(DocumentPage.placeholder_pixmap)
self.background_is_dirty = True