From cd04b3f8e8024ddc533e37c22f74c8f3f8a202ca Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Sun, 6 Oct 2019 11:56:19 +0200
Subject: [PATCH] precision argument for parallel_transport, and reducing it
 when used many times

---
 hyperpoint.cpp |  4 ++--
 shmup.cpp      | 12 ++++++------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/hyperpoint.cpp b/hyperpoint.cpp
index ce128b39..7ee51ac0 100644
--- a/hyperpoint.cpp
+++ b/hyperpoint.cpp
@@ -996,13 +996,13 @@ EX bool asign(ld y1, ld y2) { return signum(y1) != signum(y2); }
 
 EX ld xcross(ld x1, ld y1, ld x2, ld y2) { return x1 + (x2 - x1) * y1 / (y1 - y2); }
 
-EX transmatrix parallel_transport(const transmatrix Position, const transmatrix& ori, const hyperpoint direction) {
+EX transmatrix parallel_transport(const transmatrix Position, const transmatrix& ori, const hyperpoint direction, int precision IS(100)) {
   if(nonisotropic) return nisot::parallel_transport(Position, direction);
   else if(prod) {
     hyperpoint h = product::direct_exp(ori * direction);
     return Position * rgpushxto0(h);
     }
-  else return Position * rgpushxto0(direct_exp(direction, 100));
+  else return Position * rgpushxto0(direct_exp(direction, precision));
   }
 
 EX void apply_parallel_transport(transmatrix& Position, const transmatrix orientation, const hyperpoint direction) {
diff --git a/shmup.cpp b/shmup.cpp
index 7654aa8e..aa5c5228 100644
--- a/shmup.cpp
+++ b/shmup.cpp
@@ -1107,7 +1107,7 @@ void movePlayer(monster *m, int delta) {
         int i0 = i;
         for(int a=0; a<3; a++) v[a] = (i0 % 3) - 1, i0 /= 3;
         v = v * .1 / hypot_d(3, v);
-        transmatrix T1 = (i == 13) ? nat : parallel_transport(nat, m->ori, v);
+        transmatrix T1 = (i == 13) ? nat : parallel_transport(nat, m->ori, v, 2);
         cell *c3 = c2;
         while(true) {
           cell *c4 = findbaseAround(tC0(T1), c3, 1);
@@ -1634,10 +1634,10 @@ void moveBullet(monster *m, int delta) {
     m->dead = true;
 
   if(inertia_based) {
-    nat = parallel_transport(nat, m->ori, m->inertia * delta);
+    nat = parallel_transport(nat, m->ori, m->inertia * delta, 10);
     }
   else 
-    nat = parallel_transport(nat, m->ori, fronttangent(delta * SCALE * m->vel / speedfactor()));
+    nat = parallel_transport(nat, m->ori, fronttangent(delta * SCALE * m->vel / speedfactor()), 10);
   cell *c2 = m->findbase(nat, 1);
 
   if(m->parent && isPlayer(m->parent) && markOrb(itOrbLava) && c2 != m->base && !isPlayerOn(m->base)) 
@@ -2111,14 +2111,14 @@ void moveMonster(monster *m, int delta) {
   
   if(inertia_based) {
     if(igo) return;
-    nat = parallel_transport(nat, m->ori, m->inertia * delta);
+    nat = parallel_transport(nat, m->ori, m->inertia * delta, 10);
     }
   else if(WDIM == 3 && igo) {
     ld fspin = rand() % 1000;  
-    nat = parallel_transport(nat0, m->ori, cspin(1,2,fspin) * spin(igospan[igo]) * xtangent(step));
+    nat = parallel_transport(nat0, m->ori, cspin(1,2,fspin) * spin(igospan[igo]) * xtangent(step), 10);
     }
   else {
-    nat = parallel_transport(nat0, m->ori, spin(igospan[igo]) * xtangent(step));
+    nat = parallel_transport(nat0, m->ori, spin(igospan[igo]) * xtangent(step), 10);
     }
 
   if(m->type != moRagingBull && !peace::on)