René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[ENH]: FancyArrow in 3D","articleBody":"### Problem\n\nHello,\r\n\r\nFancyArrow can not be used in 3D.\r\nSome proposals (#21688) consists in creating a new class.\r\nCould it be possible: \r\n1. to extend FancyArrow to 3D (as for quiver)\r\n2. to solve -if possible- the arrow head problem representation when loocking the arrow along its axis (see the 2nd plot in the figure below)\r\n\r\nThanks,\r\nPatrick\r\n\r\n```\r\nimport numpy as np\r\nimport matplotlib.pyplot as plt\r\nfrom matplotlib.patches import FancyArrowPatch, FancyArrow\r\nfrom mpl_toolkits.mplot3d import proj3d\r\n\r\n\r\nclass Arrow3D(FancyArrowPatch):\r\n    \"\"\" Create fancy arrow (artist) for 3d matplotlib visualisation \"\"\"\r\n\r\n    def __init__(self, xs, ys, zs, *args, **kwargs):\r\n        FancyArrowPatch.__init__(self, (0, 0), (0, 0), *args, **kwargs)\r\n        self._verts3d = xs, ys, zs\r\n\r\n    def draw(self, renderer):\r\n        xs3d, ys3d, zs3d = self._verts3d\r\n        xarr, yarr, _ = proj3d.proj_transform(xs3d, ys3d, zs3d, self.axes.M)\r\n        self.set_positions((xarr[0], yarr[0]), (xarr[1], yarr[1]))\r\n        FancyArrowPatch.draw(self, renderer)\r\n\r\n\r\nfig, ax = plt.subplots(1, 2, figsize=(12, 5),\r\n                       subplot_kw=dict(projection=\"3d\",\r\n                                       proj_type='ortho'))\r\n\r\nax[0].voxels(np.ones((1, 1, 1)), facecolors=[0, 0, 0, 0], edgecolors='k')\r\n# ax[0].add_artist(FancyArrow(0, 0, 0, 1, 1, 1))\r\nax[0].add_artist(Arrow3D((0, 1), (0, 1), (0, 1), mutation_scale=50))\r\n\r\nax[1].voxels(np.ones((1, 1, 1)), facecolors=[0, 0, 0, 0], edgecolors='k')\r\nax[1].view_init(elev=28, azim=45)\r\n# ax[1].add_artist(FancyArrow(0, 0, 0, 1, 1, 1)))\r\nax[1].add_artist(Arrow3D((0, 1), (0, 1), (0, 1), mutation_scale=50))\r\n\r\nplt.show()\r\n```\r\n![image](https://user-images.githubusercontent.com/16154687/155967746-2eadecad-c976-4b29-97cd-5f8858f25698.png)\r\n\r\n\n\n### Proposed solution\n\n_No response_","author":{"url":"https://github.com/patquem","@type":"Person","name":"patquem"},"datePublished":"2022-02-28T10:33:00.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":10},"url":"https://github.com/22571/matplotlib/issues/22571"}