From 2fb992e34ae0d6bf73b9450139419063c61801ce Mon Sep 17 00:00:00 2001
From: John Wiggins <jwiggins@enthought.com>
Date: Thu, 18 Mar 2021 17:58:48 +0100
Subject: [PATCH] Use BGRA32 for celiagg's default pixel format

---
 enable/qt4/celiagg.py |  4 ++--
 kiva/celiagg.py       | 13 ++++++++-----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/enable/qt4/celiagg.py b/enable/qt4/celiagg.py
index 1b3fea2c1..73fc90575 100644
--- a/enable/qt4/celiagg.py
+++ b/enable/qt4/celiagg.py
@@ -21,7 +21,7 @@ class Window(BaseWindow):
     # Keep a buffer around for converting RGBA -> BGRA
     _shuffle_buffer = Array(shape=(None, None, 4), dtype=np.uint8)
 
-    def _create_gc(self, size, pix_format="rgba32"):
+    def _create_gc(self, size, pix_format="bgra32"):
         gc = GraphicsContext(
             (size[0] + 1, size[1] + 1),
             pix_format=pix_format,
@@ -58,7 +58,7 @@ def _shuffle_copy(self):
 
         Qt's Format_RGB32 is actually BGR. So, Yeah...
         """
-        src = self._gc.gc.array
+        src = self._gc.bmp_array
         dst = self._shuffle_buffer
         src_fmt = self._gc.pix_format
 
diff --git a/kiva/celiagg.py b/kiva/celiagg.py
index 9b3b25223..05aee2947 100644
--- a/kiva/celiagg.py
+++ b/kiva/celiagg.py
@@ -87,7 +87,7 @@ def __init__(self, size, *args, **kwargs):
         super(GraphicsContext, self).__init__()
         self._width = size[0]
         self._height = size[1]
-        self.pix_format = kwargs.get('pix_format', 'rgba32')
+        self.pix_format = kwargs.get('pix_format', 'bgra32')
 
         shape = (self._height, self._width, 4)
         buffer = np.zeros(shape, dtype=np.uint8)
@@ -113,6 +113,9 @@ def __init__(self, size, *args, **kwargs):
         self.base_scale = kwargs.pop('base_pixel_scale', 1)
         self.transform.scale(self.base_scale, self.base_scale)
 
+        # Make this look like a kiva.agg GC
+        self.bmp_array = buffer
+
     # ----------------------------------------------------------------
     # Size info
     # ----------------------------------------------------------------
@@ -584,16 +587,16 @@ def normalize_image(img):
         elif isinstance(img, Image.Image):
             img, img_format = normalize_image(img)
             img_array = np.array(img)
+        elif isinstance(img, GraphicsContext):
+            img_array = img.gc.array
+            img_format = pix_formats[img.pix_format]
         elif hasattr(img, 'bmp_array'):
-            # An offscreen kiva context
+            # An offscreen kiva.agg context
             # XXX: Use a copy to kill the read-only flag which plays havoc
             # with the Cython memoryviews used by celiagg
             img = Image.fromarray(img.bmp_array)
             img, img_format = normalize_image(img)
             img_array = np.array(img)
-        elif isinstance(img, GraphicsContext):
-            img_array = img.gc.array
-            img_format = pix_formats[img.pix_format]
         else:
             msg = "Cannot render image of type '{}' into celiagg context."
             warnings.warn(msg.format(type(img)))