From 643d50813d62004f8ad7cf3f2aa6ecfc582d839c Mon Sep 17 00:00:00 2001
From: enricoturri1966 <enricoturri@seznam.cz>
Date: Thu, 26 Jan 2023 10:00:35 +0100
Subject: [PATCH] Removed function double rotation_diff_z(const Vec3d
 &rot_xyz_from, const Vec3d &rot_xyz_to) and remaining code using it

---
 src/libslic3r/Geometry.cpp    | 16 +---------------
 src/libslic3r/Geometry.hpp    |  1 -
 src/libslic3r/Model.cpp       |  2 +-
 src/libslic3r/PrintObject.cpp |  4 ++--
 4 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/src/libslic3r/Geometry.cpp b/src/libslic3r/Geometry.cpp
index 7bab0ed7a0..441825654c 100644
--- a/src/libslic3r/Geometry.cpp
+++ b/src/libslic3r/Geometry.cpp
@@ -872,24 +872,10 @@ Eigen::Quaterniond rotation_xyz_diff(const Vec3d &rot_xyz_from, const Vec3d &rot
 }
 
 // This should only be called if it is known, that the two rotations only differ in rotation around the Z axis.
-double rotation_diff_z(const Vec3d &rot_xyz_from, const Vec3d &rot_xyz_to)
-{
-    const Eigen::AngleAxisd angle_axis(rotation_xyz_diff(rot_xyz_from, rot_xyz_to));
-    const Vec3d& axis  = angle_axis.axis();
-    const double angle = angle_axis.angle();
-#ifndef NDEBUG
-    if (std::abs(angle) > 1e-8) {
-        assert(std::abs(axis.x()) < 1e-8);
-        assert(std::abs(axis.y()) < 1e-8);
-    }
-#endif /* NDEBUG */
-    return (axis.z() < 0) ? -angle : angle;
-}
-
 double rotation_diff_z(const Transform3d &trafo_from, const Transform3d &trafo_to)
 {
     auto  m  = trafo_to.linear() * trafo_from.linear().inverse();
-    assert(std::abs(m.determinant() - 1));
+    assert(std::abs(m.determinant() - 1) < EPSILON);
     Vec3d vx = m * Vec3d(1., 0., 0);
     // Verify that the linear part of rotation from trafo_from to trafo_to rotates around Z and is unity.
     assert(std::abs(std::hypot(vx.x(), vx.y()) - 1.) < 1e-5);
diff --git a/src/libslic3r/Geometry.hpp b/src/libslic3r/Geometry.hpp
index d7cf326114..0421c08068 100644
--- a/src/libslic3r/Geometry.hpp
+++ b/src/libslic3r/Geometry.hpp
@@ -546,7 +546,6 @@ extern Transform3d transform3d_from_string(const std::string& transform_str);
 extern Eigen::Quaterniond rotation_xyz_diff(const Vec3d &rot_xyz_from, const Vec3d &rot_xyz_to);
 // Rotation by Z to align rot_xyz_from to rot_xyz_to.
 // This should only be called if it is known, that the two rotations only differ in rotation around the Z axis.
-extern double rotation_diff_z(const Vec3d &rot_xyz_from, const Vec3d &rot_xyz_to);
 extern double rotation_diff_z(const Transform3d &trafo_from, const Transform3d &trafo_to);
 
 // Is the angle close to a multiple of 90 degrees?
diff --git a/src/libslic3r/Model.cpp b/src/libslic3r/Model.cpp
index b823eb4fab..bdd9bfd705 100644
--- a/src/libslic3r/Model.cpp
+++ b/src/libslic3r/Model.cpp
@@ -1780,7 +1780,7 @@ void ModelObject::bake_xy_rotation_into_meshes(size_t instance_idx)
     // Adjust the instances.
     for (size_t i = 0; i < this->instances.size(); ++ i) {
         ModelInstance &model_instance = *this->instances[i];
-        model_instance.set_rotation(Vec3d(0., 0., Geometry::rotation_diff_z(reference_trafo.get_rotation(), model_instance.get_rotation())));
+        model_instance.set_rotation(Vec3d(0., 0., Geometry::rotation_diff_z(reference_trafo.get_matrix(), model_instance.get_matrix())));
         model_instance.set_scaling_factor(Vec3d(new_scaling_factor, new_scaling_factor, new_scaling_factor));
         model_instance.set_mirror(Vec3d(1., 1., 1.));
     }
diff --git a/src/libslic3r/PrintObject.cpp b/src/libslic3r/PrintObject.cpp
index dc75fb8a32..dfa280f459 100644
--- a/src/libslic3r/PrintObject.cpp
+++ b/src/libslic3r/PrintObject.cpp
@@ -69,8 +69,8 @@ PrintObject::PrintObject(Print* print, ModelObject* model_object, const Transfor
     BoundingBoxf3  bbox        = model_object->raw_bounding_box();
     Vec3d 		   bbox_center = bbox.center();
 	// We may need to rotate the bbox / bbox_center from the original instance to the current instance.
-	double z_diff = Geometry::rotation_diff_z(model_object->instances.front()->get_rotation(), instances.front().model_instance->get_rotation());
-	if (std::abs(z_diff) > EPSILON) {
+    double z_diff = Geometry::rotation_diff_z(model_object->instances.front()->get_matrix(), instances.front().model_instance->get_matrix());
+  if (std::abs(z_diff) > EPSILON) {
 		auto z_rot  = Eigen::AngleAxisd(z_diff, Vec3d::UnitZ());
 		bbox 		= bbox.transformed(Transform3d(z_rot));
 		bbox_center = (z_rot * bbox_center).eval();