From 08bd21310cc3c774b11a1a6c27a540358cad999f Mon Sep 17 00:00:00 2001
From: Valerii Bokhan <80919135+valerii-bokhan@users.noreply.github.com>
Date: Sun, 9 Nov 2025 05:29:27 +0100
Subject: [PATCH] Fix: Correcting the behavior of the camera panning. (#11111)

* Fix: Correcting the behavior of the camera panning.

Fixes #11107
---
 src/slic3r/GUI/GLCanvas3D.cpp | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index 02db33574e..9ff422f724 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -33,6 +33,7 @@
 #include "DailyTips.hpp"
 #include "FilamentMapDialog.hpp"
 
+#include "slic3r/GUI/CameraUtils.hpp"
 #include "slic3r/GUI/Gizmos/GLGizmoPainterBase.hpp"
 #include "slic3r/Utils/UndoRedo.hpp"
 #include "slic3r/Utils/MacDarkMode.hpp"
@@ -4690,6 +4691,7 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
 
             m_camera_movement = true;
             m_mouse.drag.start_position_2D = pos;
+            m_mouse.drag.move_start_threshold_position_2D = pos;
         }
     }
     else if ((evt.LeftUp() || evt.MiddleUp() || evt.RightUp()) ||
@@ -9372,12 +9374,18 @@ Vec3d GLCanvas3D::_mouse_to_3d(const Point& mouse_pos, float* z)
     if (m_canvas == nullptr)
         return Vec3d(DBL_MAX, DBL_MAX, DBL_MAX);
 
+    const Camera& camera = wxGetApp().plater()->get_camera();
+
     if (z == nullptr) {
-        const SceneRaycaster::HitResult hit = m_scene_raycaster.hit(mouse_pos.cast<double>(), wxGetApp().plater()->get_camera(), nullptr);
+        const SceneRaycaster::HitResult hit = m_scene_raycaster.hit(mouse_pos.cast<double>(), camera, nullptr);
         return hit.is_valid() ? hit.position.cast<double>() : _mouse_to_bed_3d(mouse_pos);
     }
+    // Orca: Handling of the particular case, if we want to get the position for Z = 0
+    else if (is_approx(static_cast<double>(*z), 0.)) {
+        Vec2d position = CameraUtils::get_z0_position(camera, Vec2d(mouse_pos.x(), mouse_pos.y()));
+        return Vec3d(position.x(), position.y(), *z);
+    }
     else {
-        const Camera& camera = wxGetApp().plater()->get_camera();
         const Vec4i32 viewport(camera.get_viewport().data());
         Vec3d out;
         igl::unproject(Vec3d(mouse_pos.x(), viewport[3] - mouse_pos.y(), *z), camera.get_view_matrix().matrix(), camera.get_projection_matrix().matrix(), viewport, out);