Fix macosx backend for Matplotlib>=3.6.

anntzer · anntzer · commit 58a75a4bd5fd · 2023-09-17T23:48:22.000+02:00
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
@@ -1,6 +1,7 @@
 next
 ====
 
+- Fixed support for macos backend on Matplotlib≥3.6.
 - Support pdf MaxVersion up to 1.7 (if the underlying cairo supports it).
 
 v0.5 (2022-08-18)
diff --git a/lib/mplcairo/macosx.py b/lib/mplcairo/macosx.py
@@ -1,19 +1,46 @@
 from matplotlib.backends.backend_macosx import _BackendMac, FigureCanvasMac
 
 from . import _mplcairo
-from .base import FigureCanvasCairo
+from .base import FigureCanvasCairo, _LOCK
 
 
 class FigureCanvasMacCairo(FigureCanvasCairo, FigureCanvasMac):
 
-    def _draw(self):
-        renderer = self.get_renderer()
-        renderer.clear()
-        self.figure.draw(renderer)
-        # A bit hackish, but that's what _macosx.FigureCanvas wants...
-        self._renderer = _mplcairo.cairo_to_straight_rgba8888(
-            renderer._get_buffer())
-        return self
+    if hasattr(FigureCanvasMac, "_draw"):
+        # Matplotlib<3.6.
+
+        def _draw(self):
+            renderer = self.get_renderer()
+            renderer.clear()
+            self.figure.draw(renderer)
+            # A bit hackish, but that's what _macosx.FigureCanvas wants...
+            self._renderer = _mplcairo.cairo_to_straight_rgba8888(
+                renderer._get_buffer())
+            return self
+
+    else:
+        # Matplotlib>=3.6: just a copy-paste of FigureCanvasMac.draw, but the
+        # copy ensures that super() correctly refers to FigureCanvasCairo, not
+        # FigureCanvasAgg.
+
+        def draw(self):
+            if self._is_drawing:
+                return
+            self._is_drawing = True
+            try:
+                super().draw()
+            finally:
+                self._is_drawing = False
+            self.update()
+
+        # Inheriting from FigureCanvasCairo.restore_region would call
+        # super().draw() which would incorrectly refer to FigureCanvasAgg;
+        # directly call self.update() instead.
+
+        def restore_region(self, region):
+            with _LOCK:
+                self.get_renderer().restore_region(region)
+            self.update()
 
 
 @_BackendMac.export
