feat: extend tiles with Tiles.isLava and Tiles.isChasm

src/titles.lua

@@ -0,0 +1,37 @@
+-- Renown-gated titles: a flavor rank meta.lua's own banked renown climbs
+-- through, one tier per crossed threshold, entirely separate from a
+-- character's class - a title describes how far this save file's whole
+-- history has come, not what any single run's build looked like.
+
+local Titles = {}
+
+Titles.LADDER = {
+  { threshold = 0, name = "Whelp" },
+  { threshold = 50, name = "Delver" },
+  { threshold = 150, name = "Warden" },
+  { threshold = 350, name = "Vanquisher" },
+  { threshold = 700, name = "Warren Lord" },
+  { threshold = 1500, name = "Undying" },
+}
+
+-- The highest title whose threshold `renown` clears, walked from the top of
+-- the ladder down so a renown total that clears several thresholds at once
+-- always resolves to the hardest-earned name rather than the first match.
+function Titles.forRenown(renown)
+  for i = #Titles.LADDER, 1, -1 do
+    if renown >= Titles.LADDER[i].threshold then return Titles.LADDER[i].name end
+  end
+  return Titles.LADDER[1].name
+end
+
+-- Renown still needed to clear the next threshold above `renown`, or nil
+-- once renown has already cleared the top of the ladder and there is
+-- nothing left to climb toward.
+function Titles.toNext(renown)
+  for _, tier in ipairs(Titles.LADDER) do
+    if renown < tier.threshold then return tier.threshold - renown end
+  end
+  return nil
+end
+
+return Titles