René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"2.x: Cairo backends cannot render images","articleBody":"In testing #6540, I can see that neither Cairo backend is able to render images correctly.\n\nWith GTKCairo:\n\n``` pytb\nTraceback (most recent call last):\n  File \".../lib/matplotlib/backends/backend_gtk.py\", line 438, in expose_event\n    self._render_figure(self._pixmap, w, h)\n  File \".../lib/matplotlib/backends/backend_gtk.py\", line 426, in _render_figure\n    self.figure.draw (self._renderer)\n  File \".../lib/matplotlib/artist.py\", line 63, in draw_wrapper\n    draw(artist, renderer, *args, **kwargs)\n  File \".../lib/matplotlib/figure.py\", line 1129, in draw\n    renderer, self, dsu, self.suppressComposite)\n  File \".../lib/matplotlib/image.py\", line 139, in _draw_list_compositing_images\n    a.draw(renderer)\n  File \".../lib/matplotlib/artist.py\", line 63, in draw_wrapper\n    draw(artist, renderer, *args, **kwargs)\n  File \".../lib/matplotlib/axes/_base.py\", line 2353, in draw\n    mimage._draw_list_compositing_images(renderer, self, dsu)\n  File \".../lib/matplotlib/image.py\", line 163, in _draw_list_compositing_images\n    flush_images()\n  File \".../lib/matplotlib/image.py\", line 147, in flush_images\n    image_group[0].draw(renderer)\n  File \".../lib/matplotlib/artist.py\", line 63, in draw_wrapper\n    draw(artist, renderer, *args, **kwargs)\n  File \".../lib/matplotlib/image.py\", line 464, in draw\n    renderer.draw_image(gc, l, b, im)\n  File \".../lib/matplotlib/backends/backend_cairo.py\", line 180, in draw_image\n    im.shape[1]*4)\nTypeError: expected a writeable buffer object\n```\n\nWith GTK3Cairo:\n\n``` pytb\nTraceback (most recent call last):\n  File \".../lib/matplotlib/backends/backend_gtk3cairo.py\", line 45, in on_draw_event\n    self._render_figure(w, h)\n  File \".../lib/matplotlib/backends/backend_gtk3cairo.py\", line 34, in _render_figure\n    self.figure.draw (self._renderer)\n  File \".../lib/matplotlib/artist.py\", line 63, in draw_wrapper\n    draw(artist, renderer, *args, **kwargs)\n  File \".../lib/matplotlib/figure.py\", line 1129, in draw\n    renderer, self, dsu, self.suppressComposite)\n  File \".../lib/matplotlib/image.py\", line 139, in _draw_list_compositing_images\n    a.draw(renderer)\n  File \".../lib/matplotlib/artist.py\", line 63, in draw_wrapper\n    draw(artist, renderer, *args, **kwargs)\n  File \".../lib/matplotlib/axes/_base.py\", line 2353, in draw\n    mimage._draw_list_compositing_images(renderer, self, dsu)\n  File \".../lib/matplotlib/image.py\", line 163, in _draw_list_compositing_images\n    flush_images()\n  File \".../lib/matplotlib/image.py\", line 147, in flush_images\n    image_group[0].draw(renderer)\n  File \".../lib/matplotlib/artist.py\", line 63, in draw_wrapper\n    draw(artist, renderer, *args, **kwargs)\n  File \".../lib/matplotlib/image.py\", line 464, in draw\n    renderer.draw_image(gc, l, b, im)\n  File \".../lib/matplotlib/backends/backend_cairo.py\", line 180, in draw_image\n    im.shape[1]*4)\nTypeError: expected a writeable buffer object\n```\n\nBisect points to 659513951920d83fe6ef68ec40dd72f7bd6d6653, the backport of #5718.\n","author":{"url":"https://github.com/QuLogic","@type":"Person","name":"QuLogic"},"datePublished":"2016-06-08T21:00:44.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/6562/matplotlib/issues/6562"}