René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Issue rendering polar plot (agg backend?) with rorigin set","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\nWhen saving a png of a polar plot with the r-origin set \"by hand,\" saving the result as a png plot doesn't work as expected. Saving it as PDF works as expected. Working interactively and saving it with the UI as a png works as expected.\r\n\r\n\u003c!--A short 1-2 sentences that succinctly describes the bug--\u003e\r\n\r\n```python\r\nimport matplotlib.pyplot as plt\r\nimport numpy as np\r\nfrom matplotlib.gridspec import GridSpec\r\n\r\nnbins = 50\r\ndata = np.random.randint(0, 42, nbins)\r\n\r\nfig = plt.figure()\r\n\r\nax_g = fig.add_subplot(polar=True, facecolor=\"none\")\r\ntheta = np.array(\r\n    [np.pi/2-i*2*np.pi/len(data) for i in range(len(data))])\r\nlines = ax_g.plot(theta, data)\r\n\r\nax_g.set_rorigin(-78)  # Replacing this with ax_g.set_rmin works as expected, so the problem comes from this line.\r\n\r\nfig.savefig(\"bug.png\")\r\nfig.savefig(\"bug.pdf\")\r\n```\r\n\r\n\r\n\r\n**Actual outcome**\r\n\r\n![bug](https://user-images.githubusercontent.com/184798/82050228-0cbbbb00-96b8-11ea-8fa4-307fca02b919.png)\r\n\r\n\r\n**Expected outcome**\r\n\r\n[bug.pdf](https://github.com/matplotlib/matplotlib/files/4634337/bug.pdf)\r\n\r\n\r\n\u003c!--A description of the expected outcome from the code snippet--\u003e\r\n\u003c!--If this used to work in an earlier version of Matplotlib, please note the version it used to work on--\u003e\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: Ubuntu\r\n  * Matplotlib version: 3.2.1\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): TkAgg (tried with Agg, and other backends)\r\n  * Python version: 3.8.2\r\n  * Jupyter version (if applicable): NA\r\n  * Other libraries:  NA\r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\n\r\n","author":{"url":"https://github.com/NelleV","@type":"Person","name":"NelleV"},"datePublished":"2020-05-15T12:28:40.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/17418/matplotlib/issues/17418"}