• Zagorath@aussie.zone
    link
    fedilink
    English
    arrow-up
    1
    ·
    3 months ago

    Uhh, no. A crescent is a classic concave shape, but you can travel from any point to any other in a crescent without crossing a line, because it’s a single enclosed shape.

    • davidagain@lemmy.world
      link
      fedilink
      English
      arrow-up
      2
      ·
      3 months ago

      A crescent isn’t a convex shape though, and ironically you left out the word ‘straight’ in your rule about convex.

      • Zagorath@aussie.zone
        link
        fedilink
        English
        arrow-up
        1
        ·
        3 months ago

        No irony, I didn’t say straight because I didn’t mean straight. I meant exactly what I said: you can get from one point to another without crossing a line. Because if you have to cross a line, you’ve either moved into a different shape (in the case of two adjoining shapes) or moves into empty space.

        • davidagain@lemmy.world
          link
          fedilink
          English
          arrow-up
          1
          ·
          3 months ago

          That’s path connectedness. Convex shapes are ones in which any two points can be joined by a straight line internal to the shape.