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Source code for matplotlib.backends.backend_qt5agg

Render to qt from agg
from __future__ import (absolute_import, division, print_function,

import six

import ctypes

from matplotlib import cbook
from matplotlib.transforms import Bbox

from .backend_agg import FigureCanvasAgg
from .backend_qt5 import (
    QtCore, QtGui, QtWidgets, _BackendQT5, FigureCanvasQT, FigureManagerQT,
    NavigationToolbar2QT, backend_version)
from .qt_compat import QT_API

[docs]class FigureCanvasQTAgg(FigureCanvasAgg, FigureCanvasQT): def __init__(self, figure): super(FigureCanvasQTAgg, self).__init__(figure=figure) self._bbox_queue = [] @property @cbook.deprecated("2.1") def blitbox(self): return self._bbox_queue
[docs] def paintEvent(self, e): """Copy the image from the Agg canvas to the qt.drawable. In Qt, all drawing should be done inside of here when a widget is shown onscreen. """ if self._update_dpi(): # The dpi update triggered its own paintEvent. return self._draw_idle() # Only does something if a draw is pending. # if the canvas does not have a renderer, then give up and wait for # FigureCanvasAgg.draw(self) to be called if not hasattr(self, 'renderer'): return painter = QtGui.QPainter(self) if self._bbox_queue: bbox_queue = self._bbox_queue else: painter.eraseRect(self.rect()) bbox_queue = [ Bbox([[0, 0], [self.renderer.width, self.renderer.height]])] self._bbox_queue = [] for bbox in bbox_queue: l, b, r, t = map(int, bbox.extents) w = r - l h = t - b reg = self.copy_from_bbox(bbox) buf = reg.to_string_argb() qimage = QtGui.QImage(buf, w, h, QtGui.QImage.Format_ARGB32) # Adjust the buf reference count to work around a memory leak bug # in QImage under PySide on Python 3. if QT_API == 'PySide' and six.PY3: ctypes.c_long.from_address(id(buf)).value = 1 if hasattr(qimage, 'setDevicePixelRatio'): # Not available on Qt4 or some older Qt5. qimage.setDevicePixelRatio(self._dpi_ratio) origin = QtCore.QPoint(l, self.renderer.height - t) painter.drawImage(origin / self._dpi_ratio, qimage) self._draw_rect_callback(painter) painter.end()
[docs] def blit(self, bbox=None): """Blit the region in bbox. """ # If bbox is None, blit the entire canvas. Otherwise # blit only the area defined by the bbox. if bbox is None and self.figure: bbox = self.figure.bbox self._bbox_queue.append(bbox) # repaint uses logical pixels, not physical pixels like the renderer. l, b, w, h = [pt / self._dpi_ratio for pt in bbox.bounds] t = b + h self.repaint(l, self.renderer.height / self._dpi_ratio - t, w, h)
[docs] def print_figure(self, *args, **kwargs): super(FigureCanvasQTAgg, self).print_figure(*args, **kwargs) self.draw()
[docs]@cbook.deprecated("2.2") class FigureCanvasQTAggBase(FigureCanvasQTAgg): pass
@_BackendQT5.export class _BackendQT5Agg(_BackendQT5): FigureCanvas = FigureCanvasQTAgg