From e7b90fdb05d94a21d139adbe64822db4f51d5eef Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sat, 17 Nov 2018 19:25:15 +0100
Subject: [PATCH] fixed some minor issues with HyperRogue's 3D

---
 hyperpoint.cpp | 2 +-
 polygons.cpp   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/hyperpoint.cpp b/hyperpoint.cpp
index b297f78d..d2ed0449 100644
--- a/hyperpoint.cpp
+++ b/hyperpoint.cpp
@@ -176,7 +176,7 @@ ld sqhypot3(const hyperpoint& h) {
 ld zlevel(const hyperpoint &h) {
   if(euclid) return h[2];
   else if(sphere) return sqrt(intval(h, Hypc));
-  else return sqrt(-intval(h, Hypc));
+  else return (h[2] < 0 ? -1 : 1) * sqrt(-intval(h, Hypc));
   }
 
 // display a hyperbolic point
diff --git a/polygons.cpp b/polygons.cpp
index 1d054267..146c8655 100644
--- a/polygons.cpp
+++ b/polygons.cpp
@@ -171,7 +171,7 @@ void add1(const hyperpoint& H) {
 int spherespecial, spherephase;
 
 bool is_behind(const hyperpoint& H) {
-  return pmodel == mdDisk && vid.alpha + H[2] <= BEHIND_LIMIT;
+  return pmodel == mdDisk && (hyperbolic ? H[2] >= 0 : true) && vid.alpha + H[2] <= BEHIND_LIMIT;
   }
 
 hyperpoint be_just_on_view(const hyperpoint& H1, const hyperpoint &H2) {