From e67c7ec7b39d51d8a0ce0ada4b1a689b99b25125 Mon Sep 17 00:00:00 2001
From: Gonzalo Martinez Lema <gonzaponte@gmail.com>
Date: Thu, 2 Nov 2023 13:17:20 +0200
Subject: [PATCH] Implement and test `n4::boolean_shape::trans{,form}`

---
 nain4/src/n4-boolean-shape.hh |  7 ++++++-
 nain4/test/test-nain4.cc      | 30 ++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/nain4/src/n4-boolean-shape.hh b/nain4/src/n4-boolean-shape.hh
index 4b386738..e18103c7 100644
--- a/nain4/src/n4-boolean-shape.hh
+++ b/nain4/src/n4-boolean-shape.hh
@@ -1,5 +1,6 @@
 #pragma once
 
+#include "G4Transform3D.hh"
 #include <n4-shape.hh>
 
 #include <type_traits>
@@ -16,10 +17,14 @@ struct boolean_shape : shape {
   friend shape;
   G4VSolid* solid() const override;
 
+
+  boolean_shape& trans    (G4Transform3D&    t  )  { return transform(t); }
+  boolean_shape& transform(G4Transform3D&    t  )  { transformation =                   t         * transformation; return *this; }
+  boolean_shape& rotate   (G4RotationMatrix& r  )  { transformation = HepGeom::Rotate3D{r}        * transformation; return *this; }
   boolean_shape& rotate_x(double delta         )  { auto rot = G4RotationMatrix{}; rot.rotateX(delta);             return rotate(rot);}
   boolean_shape& rotate_y(double delta         )  { auto rot = G4RotationMatrix{}; rot.rotateY(delta);             return rotate(rot);}
   boolean_shape& rotate_z(double delta         )  { auto rot = G4RotationMatrix{}; rot.rotateZ(delta);             return rotate(rot);}
-  boolean_shape& rotate  (G4RotationMatrix& r  )  { transformation = HepGeom::Rotate3D{r}        * transformation; return *this; }
+
   boolean_shape& rot     (G4RotationMatrix& r  )  { return rotate(r); }
   boolean_shape& rot_x   (double delta         )  { return rotate_x(delta); }
   boolean_shape& rot_y   (double delta         )  { return rotate_y(delta); }
diff --git a/nain4/test/test-nain4.cc b/nain4/test/test-nain4.cc
index 8427fbdc..705125b7 100644
--- a/nain4/test/test-nain4.cc
+++ b/nain4/test/test-nain4.cc
@@ -1554,6 +1554,36 @@ TEST_CASE("nain boolean rotation", "[nain][geometry][boolean][rotation]") {
   CHECK(with_rot       -> EstimateCubicVolume(n, eps) == 0 );
 }
 
+TEST_CASE("boolean transform", "[boolean][transform]") {
+  auto l           = 3*m;
+  auto rotation    = G4RotationMatrix{}; rotation.rotateY(90 * deg);
+  auto translation = G4ThreeVector{0., 0., l/4};
+  auto transform   = G4Transform3D{rotation, translation};
+
+  auto usolid1 = n4::box("box1").xy(1*m).z(  l)
+    .sub(        n4::box("box2").yz(1*m).x(l/4))
+    .transform(transform)
+    .solid();
+
+  auto usolid2 = n4::box("box1").xy(1*m).z(  l)
+    .sub(        n4::box("box2").yz(1*m).x(l/4))
+    .trans(transform)
+    .solid();
+
+  auto n    = 100000;
+  auto eps  = 1e-3;
+  auto vbox = l * 1*m * 1*m;
+
+  // The small box is 1/4 of the big box, so the result two
+  // disconnected boxes: one with 1/2 volume and another one with 1/4
+  // volume
+  CHECK( usolid1 -> EstimateCubicVolume(n, eps) / m3 == Approx(3*vbox/4 / m3).margin(3e-3));
+  CHECK( usolid1 -> EstimateCubicVolume(n, eps) / m3 == Approx(3*vbox/4 / m3).margin(3e-3));
+  CHECK( usolid2 -> EstimateCubicVolume(n, eps) / m3 == Approx(3*vbox/4 / m3).margin(3e-3));
+  CHECK( usolid2 -> EstimateCubicVolume(n, eps) / m3 == Approx(3*vbox/4 / m3).margin(3e-3));
+}
+
+
 TEST_CASE("nain envelope_of", "[nain][envelope_of]") {
   auto material_1 = n4::material("G4_Fe");
   auto material_2 = n4::material("G4_Au");