Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/matplotlib/backends/backend_qt5agg.py

@@ -0,0 +1,87 @@
+"""
+Render to qt from agg.
+"""
+
+import ctypes
+
+from matplotlib.transforms import Bbox
+
+from .. import cbook
+from .backend_agg import FigureCanvasAgg
+from .backend_qt5 import (
+    QtCore, QtGui, QtWidgets, _BackendQT5, FigureCanvasQT, FigureManagerQT,
+    NavigationToolbar2QT, backend_version)
+from .qt_compat import QT_API, _setDevicePixelRatioF
+
+
+class FigureCanvasQTAgg(FigureCanvasAgg, FigureCanvasQT):
+
+    def __init__(self, figure):
+        # Must pass 'figure' as kwarg to Qt base class.
+        super().__init__(figure=figure)
+
+    def paintEvent(self, event):
+        """
+        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)
+        try:
+            # See documentation of QRect: bottom() and right() are off
+            # by 1, so use left() + width() and top() + height().
+            rect = event.rect()
+            # scale rect dimensions using the screen dpi ratio to get
+            # correct values for the Figure coordinates (rather than
+            # QT5's coords)
+            width = rect.width() * self._dpi_ratio
+            height = rect.height() * self._dpi_ratio
+            left, top = self.mouseEventCoords(rect.topLeft())
+            # shift the "top" by the height of the image to get the
+            # correct corner for our coordinate system
+            bottom = top - height
+            # same with the right side of the image
+            right = left + width
+            # create a buffer using the image bounding box
+            bbox = Bbox([[left, bottom], [right, top]])
+            reg = self.copy_from_bbox(bbox)
+            buf = cbook._unmultiplied_rgba8888_to_premultiplied_argb32(
+                memoryview(reg))
+
+            # clear the widget canvas
+            painter.eraseRect(rect)
+
+            qimage = QtGui.QImage(buf, buf.shape[1], buf.shape[0],
+                                  QtGui.QImage.Format_ARGB32_Premultiplied)
+            _setDevicePixelRatioF(qimage, self._dpi_ratio)
+            # set origin using original QT coordinates
+            origin = QtCore.QPoint(rect.left(), rect.top())
+            painter.drawImage(origin, qimage)
+            # Adjust the buf reference count to work around a memory
+            # leak bug in QImage under PySide on Python 3.
+            if QT_API in ('PySide', 'PySide2'):
+                ctypes.c_long.from_address(id(buf)).value = 1
+
+            self._draw_rect_callback(painter)
+        finally:
+            painter.end()
+
+    def print_figure(self, *args, **kwargs):
+        super().print_figure(*args, **kwargs)
+        self.draw()
+
+
+@_BackendQT5.export
+class _BackendQT5Agg(_BackendQT5):
+    FigureCanvas = FigureCanvasQTAgg