René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Mirror groups","articleBody":"A mirror group would mirror entities and meshes against a specified workplane (exactly one). This makes it possible to achieve the following forms of symmetry, starting from the shape `∀∃`:\n1. by using a mirror group once:\n   \n   ```\n   ∀∃ E∀\n   ```\n2. by using a mirror group twice, with the same initial group active during second \"Mirror\" command\n   \n   ```\n   ∀∃ E∀\n   A∃\n   ```\n3. by using a mirror group twice, with the first mirror group active during second \"Mirror\" command\n   \n   ```\n   ∀∃ E∀\n   A∃ EA\n   ```\n\nUnresolved questions: whether there should also be a way to use a point and a normal, while locked in workplane, to specify the mirror plane. It adds some logic, but may be more convenient, especially later in a sketch when none of the reference planes are handy.\n\nFeature originally requested by Fong Lin.\n","author":{"url":"https://github.com/whitequark","@type":"Person","name":"whitequark"},"datePublished":"2016-10-14T01:07:15.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":36},"url":"https://github.com/72/solvespace/issues/72"}