Simplify wx rubberband drawing.

anntzer · anntzer · commit 7465670e6a95 · 2020-09-28T19:45:38.000+02:00
Like for qt/gtk, it's much easier to just draw the rectangle at
gui_repaint time.

AFAICT this now works on Wayland too.
diff --git a/lib/matplotlib/backends/backend_wx.py b/lib/matplotlib/backends/backend_wx.py
@@ -528,8 +528,8 @@ def __init__(self, parent, id, figure):
         # Create the drawing bitmap
         self.bitmap = wx.Bitmap(w, h)
         _log.debug("%s - __init__() - bitmap w:%d h:%d", type(self), w, h)
-        # TODO: Add support for 'point' inspection and plot navigation.
         self._isDrawn = False
+        self._rubberband_rect = None
 
         self.Bind(wx.EVT_SIZE, self._onSize)
         self.Bind(wx.EVT_PAINT, self._onPaint)
@@ -628,20 +628,22 @@ def gui_repaint(self, drawDC=None, origin='WX'):
         _log.debug("%s - gui_repaint()", type(self))
         # The "if self" check avoids a "wrapped C/C++ object has been deleted"
         # RuntimeError if doing things after window is closed.
-        if self and self.IsShownOnScreen():
-            if not drawDC:
-                # not called from OnPaint use a ClientDC
-                drawDC = wx.ClientDC(self)
-
-            # following is for 'WX' backend on Windows
-            # the bitmap can not be in use by another DC,
-            # see GraphicsContextWx._cache
-            if wx.Platform == '__WXMSW__' and origin == 'WX':
-                img = self.bitmap.ConvertToImage()
-                bmp = img.ConvertToBitmap()
-                drawDC.DrawBitmap(bmp, 0, 0)
-            else:
-                drawDC.DrawBitmap(self.bitmap, 0, 0)
+        if not (self and self.IsShownOnScreen()):
+            return
+        if not drawDC:  # not called from OnPaint use a ClientDC
+            drawDC = wx.ClientDC(self)
+        # For 'WX' backend on Windows, the bitmap can not be in use by another
+        # DC (see GraphicsContextWx._cache).
+        bmp = (self.bitmap.ConvertToImage().ConvertToBitmap()
+               if wx.Platform == '__WXMSW__' and origin == 'WX'
+               else self.bitmap)
+        drawDC.DrawBitmap(bmp, 0, 0)
+        if self._rubberband_rect is not None:
+            x0, y0, x1, y1 = self._rubberband_rect
+            drawDC.DrawLineList(
+                [(x0, y0, x1, y0), (x1, y0, x1, y1),
+                 (x0, y0, x0, y1), (x0, y1, x1, y1)],
+                wx.Pen('BLACK', 1, wx.PENSTYLE_SHORT_DASH))
 
     filetypes = {
         **FigureCanvasBase.filetypes,
@@ -1250,58 +1252,13 @@ def release_zoom(self, event):
                     self._zoomAxes = None
 
     def draw_rubberband(self, event, x0, y0, x1, y1):
-        if self._retinaFix:  # On Macs, use the following code
-            # wx.DCOverlay does not work properly on Retina displays.
-            rubberBandColor = '#C0C0FF'
-            if self._prevZoomRect:
-                self._prevZoomRect.pop(0).remove()
-            self.canvas.restore_region(self._savedRetinaImage)
-            X0, X1 = self._zoomStartX, event.xdata
-            Y0, Y1 = self._zoomStartY, event.ydata
-            lineX = (X0, X0, X1, X1, X0)
-            lineY = (Y0, Y1, Y1, Y0, Y0)
-            self._prevZoomRect = self._zoomAxes.plot(
-                lineX, lineY, '-', color=rubberBandColor)
-            self._zoomAxes.draw_artist(self._prevZoomRect[0])
-            self.canvas.blit(self._zoomAxes.bbox)
-            return
-
-        # Use an Overlay to draw a rubberband-like bounding box.
-
-        dc = wx.ClientDC(self.canvas)
-        odc = wx.DCOverlay(self._wxoverlay, dc)
-        odc.Clear()
-
-        # Mac's DC is already the same as a GCDC, and it causes
-        # problems with the overlay if we try to use an actual
-        # wx.GCDC so don't try it.
-        if 'wxMac' not in wx.PlatformInfo:
-            dc = wx.GCDC(dc)
-
         height = self.canvas.figure.bbox.height
-        y1 = height - y1
-        y0 = height - y0
-
-        if y1 < y0:
-            y0, y1 = y1, y0
-        if x1 < x0:
-            x0, x1 = x1, x0
-
-        w = x1 - x0
-        h = y1 - y0
-        rect = wx.Rect(x0, y0, w, h)
+        self.canvas._rubberband_rect = (x0, height - y0, x1, height - y1)
+        self.canvas.Refresh()
 
-        rubberBandColor = '#C0C0FF'  # or load from config?
-
-        # Set a pen for the border
-        color = wx.Colour(rubberBandColor)
-        dc.SetPen(wx.Pen(color, 1))
-
-        # use the same color, plus alpha for the brush
-        r, g, b, a = color.Get(True)
-        color.Set(r, g, b, 0x60)
-        dc.SetBrush(wx.Brush(color))
-        dc.DrawRectangle(rect)
+    def remove_rubberband(self):
+        self.canvas._rubberband_rect = None
+        self.canvas.Refresh()
 
     def set_message(self, s):
         if self._coordinates:
@@ -1449,91 +1406,14 @@ def set_cursor(self, cursor):
             self._make_classic_style_pseudo_toolbar(), cursor)
 
 
-if 'wxMac' not in wx.PlatformInfo:
-    # on most platforms, use overlay
-    class RubberbandWx(backend_tools.RubberbandBase):
-        def __init__(self, *args, **kwargs):
-            super().__init__(*args, **kwargs)
-            self._wxoverlay = None
+class RubberbandWx(backend_tools.RubberbandBase):
+    def draw_rubberband(self, x0, y0, x1, y1):
+        NavigationToolbar2Wx.draw_rubberband(
+            self._make_classic_style_pseudo_toolbar(), None, x0, y0, x1, y1)
 
-        def draw_rubberband(self, x0, y0, x1, y1):
-            # Use an Overlay to draw a rubberband-like bounding box.
-            if self._wxoverlay is None:
-                self._wxoverlay = wx.Overlay()
-            dc = wx.ClientDC(self.canvas)
-            odc = wx.DCOverlay(self._wxoverlay, dc)
-            odc.Clear()
-
-            dc = wx.GCDC(dc)
-
-            height = self.canvas.figure.bbox.height
-            y1 = height - y1
-            y0 = height - y0
-
-            if y1 < y0:
-                y0, y1 = y1, y0
-            if x1 < x0:
-                x0, x1 = x1, x0
-
-            w = x1 - x0
-            h = y1 - y0
-            rect = wx.Rect(x0, y0, w, h)
-
-            rubberBandColor = '#C0C0FF'  # or load from config?
-
-            # Set a pen for the border
-            color = wx.Colour(rubberBandColor)
-            dc.SetPen(wx.Pen(color, 1))
-
-            # use the same color, plus alpha for the brush
-            r, g, b, a = color.Get(True)
-            color.Set(r, g, b, 0x60)
-            dc.SetBrush(wx.Brush(color))
-            dc.DrawRectangle(rect)
-
-        def remove_rubberband(self):
-            if self._wxoverlay is None:
-                return
-            self._wxoverlay.Reset()
-            self._wxoverlay = None
-
-else:
-    # on Mac OS retina displays DCOverlay does not work
-    # and dc.SetLogicalFunction does not have an effect on any display
-    # the workaround is to blit the full image for remove_rubberband
-    class RubberbandWx(backend_tools.RubberbandBase):
-        def __init__(self, *args, **kwargs):
-            super().__init__(*args, **kwargs)
-            self._rect = None
-
-        def draw_rubberband(self, x0, y0, x1, y1):
-            dc = wx.ClientDC(self.canvas)
-            # this would be required if the Canvas is a ScrolledWindow,
-            # which is not the case for now
-            # self.PrepareDC(dc)
-
-            # delete old rubberband
-            if self._rect:
-                self.remove_rubberband(dc)
-
-            # draw new rubberband
-            dc.SetPen(wx.Pen(wx.BLACK, 1, wx.SOLID))
-            dc.SetBrush(wx.TRANSPARENT_BRUSH)
-            self._rect = (x0, self.canvas._height-y0, x1-x0, -y1+y0)
-            dc.DrawRectangle(self._rect)
-
-        def remove_rubberband(self, dc=None):
-            if not self._rect:
-                return
-            if self.canvas.bitmap:
-                if dc is None:
-                    dc = wx.ClientDC(self.canvas)
-                dc.DrawBitmap(self.canvas.bitmap, 0, 0)
-                #  for testing the method on Windows, use this code instead:
-                # img = self.canvas.bitmap.ConvertToImage()
-                # bmp = img.ConvertToBitmap()
-                # dc.DrawBitmap(bmp, 0, 0)
-            self._rect = None
+    def remove_rubberband(self):
+        NavigationToolbar2Wx.remove_rubberband(
+            self._make_classic_style_pseudo_toolbar())
 
 
 class _HelpDialog(wx.Dialog):
