From 644d20cd892468b63eb553deaf4fa1994003cabc Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Thu, 20 Aug 2020 16:12:04 +0200
Subject: [PATCH] smartrange area-based

---
 config.cpp     |  4 ++++
 debug.cpp      |  4 ++++
 hyper.h        |  1 +
 hyperpoint.cpp |  2 +-
 hypgraph.cpp   | 13 ++++++++++++-
 5 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/config.cpp b/config.cpp
index a3079dbc..9d45fc4f 100644
--- a/config.cpp
+++ b/config.cpp
@@ -554,6 +554,7 @@ EX void initConfig() {
   addsaver(vid.use_smart_range, "smart-range", 0);
   addsaver(vid.smart_range_detail, "smart-range-detail", 8);
   addsaver(vid.smart_range_detail_3, "smart-range-detail", 30);
+  addsaver(vid.smart_area_based, "smart-area-based", false);
   addsaver(vid.cells_drawn_limit, "limit on cells drawn", 10000);
   addsaver(vid.cells_generated_limit, "limit on cells generated", 250);
   
@@ -1004,6 +1005,9 @@ EX void edit_sightrange() {
         dialog::addSelItem(XLAT("game range bonus"), its(gamerange_bonus), 'S');
         dialog::add_action([] () { gamerange_bonus = sightrange_bonus; doOvergenerate(); });
         }      
+      if(vid.use_smart_range && WDIM == 2) {
+        dialog::addBoolItem_action(XLAT("area-based range"), vid.smart_area_based, 'A');
+        }
       if(!allowChangeRange() || !allowIncreasedSight()) {
         dialog::addItem(XLAT("enable the cheat mode for additional options"), 'X');
         dialog::add_action(enable_cheat);
diff --git a/debug.cpp b/debug.cpp
index b8c49729..0652ad8e 100644
--- a/debug.cpp
+++ b/debug.cpp
@@ -798,6 +798,10 @@ int read_cheat_args() {
     vid.use_smart_range = 2;
     shift_arg_formula(WDIM == 3 ? vid.smart_range_detail_3 : vid.smart_range_detail);
     }
+  else if(argis("-smartarea")) {
+    PHASEFROM(2); cheat();
+    shift(); vid.smart_area_based = argi();
+    }
   else if(argis("-smartn")) {
     PHASEFROM(2);
     vid.use_smart_range = 1;
diff --git a/hyper.h b/hyper.h
index 45f9de53..9a3e00cd 100644
--- a/hyper.h
+++ b/hyper.h
@@ -341,6 +341,7 @@ struct videopar {
   int use_smart_range;  // 0 = distance-based, 1 = model-based, 2 = model-based and generate
   ld smart_range_detail;// minimum visible cell for modes 1 and 2
   ld smart_range_detail_3;// minimum visible cell in 3D (for mode 2, there is no mode 1)
+  bool smart_area_based;// based on area or length?
   int cells_drawn_limit;
   int cells_generated_limit; // limit on cells generated per frame
   
diff --git a/hyperpoint.cpp b/hyperpoint.cpp
index 742777ee..33bba721 100644
--- a/hyperpoint.cpp
+++ b/hyperpoint.cpp
@@ -897,7 +897,7 @@ EX ld det3(const transmatrix& T) {
 /** determinant */
 EX ld det(const transmatrix& T) {
   if(GDIM == 2) 
-    retrun det3(T);
+    return det3(T);
   else {
     ld det = 1;
     transmatrix M = T;
diff --git a/hypgraph.cpp b/hypgraph.cpp
index 2a7925c5..f882b396 100644
--- a/hypgraph.cpp
+++ b/hypgraph.cpp
@@ -1168,18 +1168,29 @@ EX bool in_smart_range(const shiftmatrix& T) {
 
   ld epsilon = 0.01;
   
+  transmatrix ar;
+  
   ld dx = 0, dy = 0, dz = 0, dh[MAXMDIM];
   for(int i=0; i<GDIM; i++) {    
     hyperpoint h2;
     applymodel(T * cpush0(i, epsilon), h2);
     ld x1 = current_display->radius * abs(h2[0] - h1[0]) / epsilon;
     ld y1 = current_display->radius * abs(h2[1] - h1[1]) * pconf.stretch / epsilon;
+    
+    for(int j=0; j<GDIM; j++) ar[i][j] = current_display->radius * (h2[j]-h1[j]) / epsilon;
+    
     dx = max(dx, x1); dy = max(dy, y1);
     if(GDIM == 3) dz = max(dz, abs(h2[2] - h1[2]));
     dh[i] = hypot(x1, y1);
     }
   
-  if(GDIM == 3) { 
+  if(GDIM == 2 && vid.smart_area_based) {
+    ld area = det2(ar);
+    ld scale = sqrt(area) * cgi.scalefactor * hcrossf7;
+    if(scale <= vid.smart_range_detail) return false;
+    }
+  
+  else if(GDIM == 3) { 
     if(-h1[2] + 2 * dz < pconf.clip_min || -h1[2] - 2 * dz > pconf.clip_max) return false;
     sort(dh, dh+GDIM); 
     ld scale = sqrt(dh[1] * dh[2]) * cgi.scalefactor * hcrossf7;