From 01dc4997dc11cb97de7486371d636caaa5d95eec Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sun, 11 Nov 2018 10:40:35 +0100
Subject: [PATCH] rogueviz:: added the sunflower spirals

---
 rogueviz-sunflower.cpp | 92 ++++++++++++++++++++++++++++++++++++++++++
 rogueviz.cpp           |  1 +
 2 files changed, 93 insertions(+)
 create mode 100644 rogueviz-sunflower.cpp

diff --git a/rogueviz-sunflower.cpp b/rogueviz-sunflower.cpp
new file mode 100644
index 00000000..74b449e3
--- /dev/null
+++ b/rogueviz-sunflower.cpp
@@ -0,0 +1,92 @@
+// non-Euclidean sunflower spirals (aka golden spirals or Fibonacci spirals)
+// Copyright (C) 2018 Zeno and Tehora Rogue, see 'hyper.cpp' for details
+
+// use: commandline parameter -sunflower <quantity> <density>
+// e.g.: hyper -sunflower 10000 0.01
+
+// for spherical geometry, density is set automatically to cover the whole sphere
+
+namespace hr {
+
+namespace sunflower {
+
+int qty = 100;
+ld density = 1, zdensity;
+
+static const int maxfib = 300000;
+
+hyperpoint ps[maxfib];
+
+hyperpoint p(int i) {
+  ld step = M_PI * (3 - sqrt(5));
+  return spin(i * step) * xpush(sphere ? (i+.5) * M_PI / qty : euclid ? sqrt((i+.5) * density) : acosh(1 + (i+.5) * density)) * C0;
+  }
+
+int inext[maxfib], inext2[maxfib];
+
+const vector<int> fibs = 
+  {1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811};
+  
+bool sunflower_cell(cell *c, transmatrix V) {
+  density = zdensity / 100;
+  if(c == cwt.at) {
+    for(int i=0; i<qty; i++) ps[i] = V * p(i);
+
+    for(int i=0; i<qty; i++) {
+      ld ba = 99;
+      ld bb = 99;
+      int bi = 0, bj = 0;
+      for(int a: fibs) {
+        if(a>i) break;
+        if(hdist(ps[i], ps[i-a]) < ba)
+          bb = ba, bj = bi, ba = hdist(ps[i], ps[i-a]), bi = i-a;
+        else if(hdist(ps[i], ps[i-a]) < bb)
+          bb = hdist(ps[i], ps[i-a]), bj = i-a;
+        }
+      inext[i] = bi;
+      inext2[i] = bj;
+      }
+
+    for(int i=0; i<qty; i++) {    
+      if(inext[inext[i]] == inext2[i] || inext2[inext[i]] == inext2[i] || inext[inext2[i]] == inext[i] || inext2[inext2[i]] == inext[i]) {
+        curvepoint(ps[i]);
+        curvepoint(ps[inext[i]]);
+        curvepoint(ps[inext2[i]]);
+        queuecurve(0xFFFFFFFF, 0x00C000FF, PPR::LINE);
+        }      
+      else {
+        curvepoint(ps[i]);
+        curvepoint(ps[inext[i]]);
+        curvepoint(ps[inext[i] + inext2[i] - i]);
+        curvepoint(ps[inext2[i]]);
+        queuecurve(0xFFFFFFFF, 0x0000C0FF, PPR::LINE);
+        }
+      }
+    }
+  return true;
+  }
+
+int readArgs() {
+  using namespace arg;
+           
+  if(0) ;
+  else if(argis("-sunflower")) {
+    shift(); qty = argi();
+    shift(); zdensity = argf() * 100;
+    patterns::whichShape = '9';
+    nohud = true;
+    addHook(hooks_drawcell, 100, sunflower_cell);
+    addHook(hooks_mainmenu, 100, [] () {
+      dialog::addItem("sunflower", 1001); 
+      dialog::add_action([] () { dialog::editNumber(zdensity, 0, 1, .1, 1, "density", "density"); });
+      });
+    }
+  else return 1;
+  return 0;
+  }
+
+auto hook = addHook(hooks_args, 100, readArgs);
+ 
+}
+
+}
\ No newline at end of file
diff --git a/rogueviz.cpp b/rogueviz.cpp
index 48bc5d9d..c25c45d5 100644
--- a/rogueviz.cpp
+++ b/rogueviz.cpp
@@ -2278,3 +2278,4 @@ auto hooks  =
 #include "rogueviz-pentagonal.cpp"
 #include "rogueviz-graph.cpp"
 #include "rogueviz-fundamental.cpp"
+#include "rogueviz-sunflower.cpp"