From 5483ec8779f232f9c2130a4589ec6a706f60c8a3 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Fri, 24 May 2019 21:42:30 +0200
Subject: [PATCH] mini-map correct in all circumstances, including vertical
 movement or y/z rotation

---
 graph.cpp | 32 +++++++++++++++++++-------------
 hud.cpp   | 10 +++++-----
 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/graph.cpp b/graph.cpp
index 8d92ee43..044ac9a1 100644
--- a/graph.cpp
+++ b/graph.cpp
@@ -722,9 +722,12 @@ bool drawing_usershape_on(cell *c, mapeditor::eShapegroup sg) {
   }
 
 ld max_eu_dist = 0;
+transmatrix radar_transform;
 
 void addradar(const transmatrix& V, char ch, color_t col, color_t outline) {
   hyperpoint h = tC0(V);
+  if(GDIM == 3 && WDIM == 2) h = tC0(radar_transform * V);
+
   using namespace hyperpoint_vec;
   ld d = hdist0(h);
   if(d > sightranges[geometry]) return;
@@ -732,26 +735,14 @@ void addradar(const transmatrix& V, char ch, color_t col, color_t outline) {
     if(d) h = h * (d / sightranges[geometry] / hypot_d(3, h));
     }
   else if(hyperbolic) {
-    ld z = h[2] + h[1]/1000000;
-    h[1] = hypot(h[1], h[2]) / (1 + h[3]);
-    // we add h[1]/1000000 so that it also works for h[2] == 0
-    if(z < 0) h[1] = -h[1];
-    h[0] = h[0] / (1 + h[3]);
-    h[2] = 0;
+    for(int a=0; a<3; a++) h[a] = h[a] / (1 + h[3]);
     }
   else if(sphere) {
-    ld z = h[2] + h[1]/1000000;
-    h[1] = hypot(h[2], h[1]);
-    if(z < 0) h[1] = -h[1];
     h[2] = h[3];
     }
   else {
-    ld z = h[2] + h[1]/1000000;
     if(d > max_eu_dist) max_eu_dist = d;
     if(d) h = h * (d / (max_eu_dist + scalefactor/4) / hypot_d(3, h));
-    h[1] = hypot(h[1], h[2]) / (1 + h[3]);
-    if(z < 0) h[1] = -h[1];
-    h[2] = 0;
     }
   radarpoints.emplace_back(radarpoint{h, ch, col, outline});
   }
@@ -6711,6 +6702,21 @@ void make_actual_view() {
 
 transmatrix cview() {
   make_actual_view();
+  if(GDIM == 3 && WDIM == 2) {
+    transmatrix T = actual_view_transform * View;
+    transmatrix U = inverse(T);
+    
+    if(T[0][2]) 
+      T = spin(-atan2(T[0][2], T[1][2])) * T;
+    if(T[1][2] && T[2][2]) 
+      T = cspin(1, 2, -atan2(T[1][2], T[2][2])) * T;
+
+    ld z = -asin_auto(tC0(inverse(T)) [2]);
+    T = zpush(-z) * T;
+
+    radar_transform = T * U;
+    }
+  
   return actual_view_transform * View;
   }
 
diff --git a/hud.cpp b/hud.cpp
index 571174c3..6c9e5892 100644
--- a/hud.cpp
+++ b/hud.cpp
@@ -354,7 +354,7 @@ extern ld max_eu_dist;
 
 void draw_radar(bool cornermode) {
 
-  bool d3 = WDIM == 3 || straightDownSeek || !vid.fixed_yz;
+  bool d3 = WDIM == 3;
   bool hyp = hyperbolic;
   bool sph = sphere;
 
@@ -400,14 +400,14 @@ void draw_radar(bool cornermode) {
   glflush();
 
   for(auto& r: radarpoints)
-    if(d3 || sphere) displaychr(int(cx + rad * r.h[0]), int(cy - rad * r.h[2] * si + rad * r.h[1] * co), 0, 8, r.glyph, r.color);
-    else if(sph) displaychr(int(cx + (rad-10) * r.h[0]), int(cy + (rad-10) * r.h[2] * si - (rad-10) * r.h[1] * co), 0, -r.h[1] * si > r.h[2] * co ? 8 : 16, r.glyph, r.color);
+    if(d3) displaychr(int(cx + rad * r.h[0]), int(cy - rad * r.h[2] * si + rad * r.h[1] * co), 0, 8, r.glyph, r.color);
+    else if(sph) displaychr(int(cx + (rad-10) * r.h[0]), int(cy + (rad-10) * r.h[2] * si + (rad-10) * r.h[1] * co), 0, +r.h[1] * si > r.h[2] * co ? 8 : 16, r.glyph, r.color);
     else if(hyp) {
       int siz = 1/(1+r.h[3]) * scalefactor * current_display->radius / (inHighQual ? 10 : 6);
-      displaychr(int(cx + rad * r.h[0]), int(cy - rad * r.h[1]), 0, siz, r.glyph, r.color);
+      displaychr(int(cx + rad * r.h[0]), int(cy + rad * r.h[1]), 0, siz, r.glyph, r.color);
       }
     else {
-      displaychr(int(cx + rad * r.h[0]), int(cy - rad * r.h[1]), 0, rad * scalefactor / (max_eu_dist + scalefactor/4) * 0.8, r.glyph, r.color);
+      displaychr(int(cx + rad * r.h[0]), int(cy + rad * r.h[1]), 0, rad * scalefactor / (max_eu_dist + scalefactor/4) * 0.8, r.glyph, r.color);
       }    
   }