Fix UI hanging on Mac

src/slic3r/GUI/GradientCurveEditor.cpp

@@ -85,6 +85,14 @@ GradientCurveEditor::GradientCurveEditor(wxWindow* parent,
     });
 }
 
+GradientCurveEditor::~GradientCurveEditor()
+{
+    // See MixedFilamentDialog::~MixedFilamentDialog: a widget destroyed while it
+    // still holds the capture wedges mouse input for the whole application.
+    if (HasCapture())
+        ReleaseMouse();
+}
+
 void GradientCurveEditor::set_points(const PointList& pts)
 {
     m_points = pts;

src/slic3r/GUI/GradientCurveEditor.hpp

@@ -36,6 +36,8 @@ public:
                         const wxColour& color_low  = wxColour(217, 217, 217),
                         const wxColour& color_high = wxColour(217, 217, 217));
 
+    ~GradientCurveEditor() override;
+
     // Replace the entire point list. The widget enforces x in [0,1], y in [0,1],
     // sorts by x, and clamps the first / last x to 0 / 1. Tangent overrides are
     // preserved as-is (NaN entries continue to use PCHIP defaults).

src/slic3r/GUI/MixedFilamentDialog.cpp

@@ -154,6 +154,18 @@ MixedFilamentDialog::MixedFilamentDialog(wxWindow* parent,
         m_preview_bmp_three = wxBitmap(img);
 }
 
+MixedFilamentDialog::~MixedFilamentDialog()
+{
+    // Backstop: a child must never be destroyed while it still holds the mouse
+    // capture. wxWidgets only asserts about this (compiled out in release), and
+    // the macOS port never unwinds its capture stack, so the stale entry would
+    // make wxNSWindow::sendEvent swallow every mouse event in the application.
+    if (m_ratio_bar && m_ratio_bar->HasCapture())
+        m_ratio_bar->ReleaseMouse();
+    if (m_triangle_panel && m_triangle_panel->HasCapture())
+        m_triangle_panel->ReleaseMouse();
+}
+
 MixedFilamentDialog::MixedFilamentDialog(wxWindow* parent,
                                          const MixedFilamentResult& existing,
                                          const std::vector<std::string>& physical_colors,
@@ -892,24 +904,30 @@ wxBoxSizer* MixedFilamentDialog::create_ratio_slider()
     m_ratio_bar->Bind(wxEVT_LEFT_DOWN, [this](wxMouseEvent& e) {
         if (m_ratio_editor_panel && m_ratio_editor_panel->IsShown())
             commit_ratio_editor(true);
-        m_dragging = true;
+        m_ratio_dragging = true;
-        m_ratio_bar->CaptureMouse();
+        if (!m_ratio_bar->HasCapture())
+            m_ratio_bar->CaptureMouse();
         int new_ratio = 100 - (int)(e.GetX() * 100.0 / m_ratio_bar->GetClientSize().GetWidth() + 0.5);
         on_ratio_changed(std::max(MIN_COMPONENT_RATIO, std::min(100 - MIN_COMPONENT_RATIO, new_ratio)));
     });
 
     m_ratio_bar->Bind(wxEVT_MOTION, [this](wxMouseEvent& e) {
-        if (!m_dragging) return;
+        if (!m_ratio_dragging) return;
         int new_ratio = 100 - (int)(e.GetX() * 100.0 / m_ratio_bar->GetClientSize().GetWidth() + 0.5);
         on_ratio_changed(std::max(MIN_COMPONENT_RATIO, std::min(100 - MIN_COMPONENT_RATIO, new_ratio)));
     });
 
+    // Release whenever the capture is held, not only when the drag flag is set:
+    // the flag can be cleared behind our back, and a capture that outlives the
+    // widget wedges mouse input for the whole application.
     m_ratio_bar->Bind(wxEVT_LEFT_UP, [this](wxMouseEvent&) {
-        if (m_dragging) {
+        m_ratio_dragging = false;
-            m_dragging = false;
+        if (m_ratio_bar->HasCapture())
-            if (m_ratio_bar->HasCapture())
+            m_ratio_bar->ReleaseMouse();
-                m_ratio_bar->ReleaseMouse();
+    });
-        }
+
+    m_ratio_bar->Bind(wxEVT_MOUSE_CAPTURE_LOST, [this](wxMouseCaptureLostEvent&) {
+        m_ratio_dragging = false;
     });
 
     sizer->Add(m_ratio_bar, 0, wxEXPAND);
@@ -1122,11 +1140,12 @@ wxBoxSizer* MixedFilamentDialog::create_triangle_picker()
             // clicks outside the triangle must not change the mix ratio.
             if (!tri_contains(p, v0, v1, v2))
                 return;
-            m_dragging = true;
+            m_tri_dragging = true;
-            m_triangle_panel->CaptureMouse();
+            if (!m_triangle_panel->HasCapture())
+                m_triangle_panel->CaptureMouse();
         }
 
-        if (!m_dragging) return;
+        if (!m_tri_dragging) return;
 
         TriPoint clamped = tri_clamp(p, v0, v1, v2);
         tri_barycentric(clamped, v0, v1, v2, m_tri_wx, m_tri_wy, m_tri_wz);
@@ -1161,15 +1180,16 @@ wxBoxSizer* MixedFilamentDialog::create_triangle_picker()
         handle_mouse(e, true);
     });
     m_triangle_panel->Bind(wxEVT_MOTION, [this, handle_mouse](wxMouseEvent& e) {
-        if (m_dragging)
+        if (m_tri_dragging)
             handle_mouse(e, false);
     });
     m_triangle_panel->Bind(wxEVT_LEFT_UP, [this](wxMouseEvent&) {
-        if (m_dragging) {
+        m_tri_dragging = false;
-            m_dragging = false;
+        if (m_triangle_panel->HasCapture())
-            if (m_triangle_panel->HasCapture())
+            m_triangle_panel->ReleaseMouse();
-                m_triangle_panel->ReleaseMouse();
+    });
-        }
+    m_triangle_panel->Bind(wxEVT_MOUSE_CAPTURE_LOST, [this](wxMouseCaptureLostEvent&) {
+        m_tri_dragging = false;
     });
 
     sizer->Add(m_triangle_panel, 0);

src/slic3r/GUI/MixedFilamentDialog.hpp

@@ -53,6 +53,8 @@ public:
                         const std::vector<std::string>& physical_names,
                         const std::vector<std::string>& physical_types = {});
 
+    ~MixedFilamentDialog();
+
     MixedFilamentResult get_result() const { return m_result; }
 
 protected:
@@ -160,8 +162,11 @@ private:
     wxBitmap                    m_preview_bmp_two;
     wxBitmap                    m_preview_bmp_three;
 
-    // Drag state
+    // Drag state. The ratio bar and the triangle picker capture the mouse
-    bool   m_dragging{false};
+    // independently, so they must not share a flag: a mouse-up on one would
+    // otherwise clear the other's flag and skip its ReleaseMouse().
+    bool   m_ratio_dragging{false};
+    bool   m_tri_dragging{false};
     std::vector<size_t> m_ratio_manual_order;
     size_t m_ratio_editor_idx{0};
     bool   m_ratio_editor_committing{false};

src/slic3r/GUI/TextureImportDialog.cpp

@@ -184,6 +184,7 @@ public:
     GreenSlider(wxWindow* parent, int value, int minVal, int maxVal,
                 const wxPoint& pos = wxDefaultPosition,
                 const wxSize& size = wxDefaultSize);
+    ~GreenSlider() override;
     int  GetValue() const;
     void SetValue(int val);
     bool Enable(bool enable = true) override;
@@ -213,6 +214,15 @@ GreenSlider::GreenSlider(wxWindow* parent, int value, int minVal, int maxVal,
     Bind(wxEVT_LEFT_DOWN, &GreenSlider::OnMouse, this);
     Bind(wxEVT_LEFT_UP,   &GreenSlider::OnMouse, this);
     Bind(wxEVT_MOTION,    &GreenSlider::OnMouse, this);
+    Bind(wxEVT_MOUSE_CAPTURE_LOST, [this](wxMouseCaptureLostEvent&) { m_dragging = false; });
+}
+
+GreenSlider::~GreenSlider()
+{
+    // See MixedFilamentDialog::~MixedFilamentDialog: a widget destroyed while it
+    // still holds the capture wedges mouse input for the whole application.
+    if (HasCapture())
+        ReleaseMouse();
 }
 
 int GreenSlider::GetValue() const { return m_value; }
@@ -302,7 +312,7 @@ void GreenSlider::OnMouse(wxMouseEvent& evt)
 
     if (evt.LeftDown()) {
         m_dragging = true;
-        CaptureMouse();
+        if (!HasCapture()) CaptureMouse();
         update(evt.GetX());
     } else if (evt.LeftUp()) {
         m_dragging = false;
@@ -1019,11 +1029,20 @@ TexturePreviewCanvas::TexturePreviewCanvas(wxWindow* parent, const wxGLAttribute
     Bind(wxEVT_MIDDLE_DOWN, &TexturePreviewCanvas::on_mouse, this);
     Bind(wxEVT_MIDDLE_UP,   &TexturePreviewCanvas::on_mouse, this);
     Bind(wxEVT_MOTION,      &TexturePreviewCanvas::on_mouse, this);
+    Bind(wxEVT_MOUSE_CAPTURE_LOST, [this](wxMouseCaptureLostEvent&) {
+        m_drag_mode = DragMode::None;
+        m_reset_overlay_pressed = false;
+    });
     Bind(wxEVT_LEAVE_WINDOW, &TexturePreviewCanvas::on_mouse, this);
 }
 
 TexturePreviewCanvas::~TexturePreviewCanvas()
 {
+    // See MixedFilamentDialog::~MixedFilamentDialog: a widget destroyed while it
+    // still holds the capture wedges mouse input for the whole application.
+    if (HasCapture())
+        ReleaseMouse();
+
     if (m_context) {
         SetCurrent(*m_context);
         if (m_tex_id)