René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Missing kerning for single-byte strings in PDF","articleBody":"### Bug report\r\n\r\n**Bug summary**\r\nKerning is not applied in the PDF output of pure single-byte strings which leads to inconsistencies between PDF and other output formats.\r\n\r\n**Code for reproduction**\r\n```python\r\nimport matplotlib.pyplot as plt\r\n\r\nfig, ax = plt.subplots()\r\nax.text(0.1, 0.5, \"ATL\", size=120)\r\nfig.savefig(\"atl.pdf\")\r\nfig.savefig(\"atl.png\", dpi=300)\r\n```\r\n\r\n**Actual outcome**\r\n![text4900](https://user-images.githubusercontent.com/12832470/109210666-6e639680-77ad-11eb-87a8-a668693c2f8b.png)\r\n\r\n**Expected outcome**\r\nI expected that the spacing between `A` and `T` is consistent between both formats. Besides this minor visual issues, I use `get_window_extent()` to place a second text item in bold next to the first one. The space between the two texts varies significantly between output formats. `get_window_extent()` considers the kerning information, so the space looks correct in PNG but is usually too small in PDF files.\r\n\r\nThe issue is related to https://github.com/matplotlib/matplotlib/issues/18282. Here the same issue was fixed for strings with multi-byte chars. I don't see the changes from https://github.com/matplotlib/matplotlib/issues/18282 in version 3.3.4, but they will not effect the single-byte string case.\r\n\r\nUnaware of https://github.com/matplotlib/matplotlib/issues/18282, I've implemented a fix for the single-byte case. I will open a PR, but you might have other ideas on how to implementation a fix.\r\n\r\n**Matplotlib version**\r\n  * Operating system: Ubuntu 16.04\r\n  * Matplotlib version: 3.3.4\r\n  * Matplotlib backend: TkAgg (but actually PDF?)\r\n  * Python version: 3.7.5\r\n  * Font: DejaVuSans Type 3\r\n\r\nI've installed matplotlib in a virtualenv with pip.\r\n","author":{"url":"https://github.com/sauerburger","@type":"Person","name":"sauerburger"},"datePublished":"2021-02-25T20:19:33.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/19581/matplotlib/issues/19581"}