From 39916901ee775d771138831580d8d0fc7a1f1dac Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Mon, 23 Apr 2018 12:50:51 +0200
Subject: [PATCH] improved square model in non-hyperbolic geometries

---
 conformal.cpp | 11 +++++++++--
 hyper.h       |  1 +
 init.cpp      |  1 +
 polygons.cpp  |  9 +++++++++
 4 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/conformal.cpp b/conformal.cpp
index db90a5c1..c2ea68ca 100644
--- a/conformal.cpp
+++ b/conformal.cpp
@@ -11,7 +11,9 @@ typedef long double precise;
 
 namespace polygonal {
 
-  typedef complex<ld> cld;
+  typedef long double xld;
+
+  typedef complex<xld> cld;
 
   int SI = 4;
   ld  STAR = 0;
@@ -66,6 +68,11 @@ namespace polygonal {
     }
   
   pair<ld, ld> compute(ld x, ld y, int prec) {
+    if(x*x+y*y > 1) {
+      xld r  = hypot(x,y);
+      x /= r;
+      y /= r;
+      }
     if(pmodel == mdPolynomial) {
       cld z(x,y);
       cld res (0,0);
@@ -92,7 +99,7 @@ namespace polygonal {
 
     for(int r=0; r<=2000; r++) {
       cld z = exp(cld(0, 2*M_PI * r / 2000.0));
-      pair<ld,ld> z2 = compute(real(z), imag(z), deg);
+      pair<xld,xld> z2 = compute(real(z), imag(z), deg);
       hyperpoint h;
       h[0] = z2.first * vid.radius;
       h[1] = z2.second * vid.radius;
diff --git a/hyper.h b/hyper.h
index 1c1f7fd0..9fc3c55c 100644
--- a/hyper.h
+++ b/hyper.h
@@ -971,6 +971,7 @@ namespace polygonal {
   extern int SI;
   extern ld STAR;
   extern int deg;
+  typedef long double xld;
   extern ld coefr[MSI], coefi[MSI];
   extern int maxcoef, coefid;
   void solve();
diff --git a/init.cpp b/init.cpp
index 8dcdc030..bf285fd2 100644
--- a/init.cpp
+++ b/init.cpp
@@ -482,6 +482,7 @@ void initAll() {
     }
   
   firstland = firstland0;
+  polygonal::solve();
   }
 
 void finishAll() {
diff --git a/polygons.cpp b/polygons.cpp
index 5b9e2fc8..34f57376 100644
--- a/polygons.cpp
+++ b/polygons.cpp
@@ -476,6 +476,15 @@ ld glhypot2(glvertex a, glvertex b) {
 void drawpolyline(polytodraw& p) {
   auto& pp = p.u.poly;
 
+  if(!hyperbolic && among(pmodel, mdPolygonal, mdPolynomial)) {
+    bool any = false;
+    for(int i=0; i<pp.cnt; i++) {
+      hyperpoint h1 = pp.V * glhr::gltopoint((*pp.tab)[pp.offset+i]);
+      if(h1[2] > 0) any = true;
+      }
+    if(!any) return;
+    }
+  
   if(sphere && pp.tinf && pp.cnt > 3) {
     int i = pp.cnt;
     pp.cnt = 3;