Remove borders and paddings from native controls on Linux (#14873)

* init

* update

* Update SpinInput.cpp

* possible fix for em_unit

* button alignment

* match titlebar height

* revert em_value for macOS and Windows

* Update GUI_Utils.hpp

* Merge branch 'main' into linux-black-borders-2

* Revert "button alignment"

This reverts commit 3fc7461071.

* Revert "match titlebar height"

This reverts commit c4aa1d9f1e.

* revert dpi changes

* match platform tags

* remove radio box borders

* Fix code indent

src/slic3r/GUI/GUI_Utils.cpp

@@ -548,7 +548,7 @@ void RemoveButtonBorder(wxWindow* win)
     GtkCssProvider* provider = gtk_css_provider_new();
 
     const char* css =
-        "button {"
+        "button, button:hover, button:active, button:focus {"
         "  border: none;"
         "  outline: none;"
         "  box-shadow: none;"
@@ -589,6 +589,58 @@ void RemoveButtonBorder(wxWindow* win)
     );
 #endif
 }
+
+void RemoveInputBorder(wxWindow* win)
+{
+    GtkWidget* widget = win->GetHandle();
+    if (!widget) return;
+
+#if GTK_CHECK_VERSION(3, 0, 0)
+    // GTK3+: use CSS provider
+    GtkCssProvider* provider = gtk_css_provider_new();
+
+    // Target 'entry' and its inner subnodes (like text selection areas)
+    const char* css =
+        "entry, entry text, entry undershoot {"
+        "  border: none;"
+        "  outline: none;"
+        "  box-shadow: none;"
+        "  padding: 0px;"
+        "  margin: 0px;"
+        "  min-height: 0px;"
+        "  min-width: 0px;"
+        "  background: none;"
+        "}";
+
+#if GTK_CHECK_VERSION(4, 0, 0)
+    // GTK4
+    gtk_css_provider_load_from_data(provider, css, -1);
+#else
+    // GTK3
+    gtk_css_provider_load_from_data(provider, css, -1, nullptr);
+#endif
+
+    GtkStyleContext* ctx = gtk_widget_get_style_context(widget);
+    gtk_style_context_add_provider(
+        ctx,
+        GTK_STYLE_PROVIDER(provider),
+        GTK_STYLE_PROVIDER_PRIORITY_USER
+    );
+    g_object_unref(provider);
+
+#else
+    // GTK2: Target the x/y thickness of the entry widget
+    gtk_rc_parse_string(
+        "style \"no-padding-entry\" {"
+        "  xthickness = 0"
+        "  ythickness = 0"
+        "  GtkEntry::inner-border = { 0, 0, 0, 0 }"
+        "  GtkEntry::focus-line-width = 0"
+        "}"
+        "class \"GtkEntry\" style \"no-padding-entry\""
+    );
+#endif
+}
 #endif // __WXGTK__
 
 #ifdef __linux__

src/slic3r/GUI/GUI_Utils.hpp

@@ -472,8 +472,9 @@ void dataview_remove_insets(wxDataViewCtrl* dv);
 void staticbox_remove_margin(wxStaticBox* sb);
 #endif
 
-#ifdef __WXGTK3__
+#ifdef __WXGTK__
-void RemoveButtonBorder(wxWindow* win);
+void RemoveButtonBorder(wxWindow* win);   // for wxButton/wxBitmapToggleButton based controls (SwitchButton, CheckBox)
+void RemoveInputBorder(wxWindow* win);    // for TextCtrl based controls (TextInput, ComboBox, SpinInput..)
 #endif
 
 #if defined(__WXOSX__) || defined(__linux__)

src/slic3r/GUI/PresetComboBoxes.cpp

@@ -865,6 +865,9 @@ PlaterPresetComboBox::PlaterPresetComboBox(wxWindow *parent, Preset::Type preset
         clr_picker = new wxBitmapButton(parent, wxID_ANY, {}, wxDefaultPosition, wxSize(FromDIP(20), FromDIP(20)), wxBU_EXACTFIT | wxBU_AUTODRAW | wxBORDER_NONE);
         clr_picker->SetBackgroundColour(StateColor::darkModeColorFor(*wxWHITE));
         clr_picker->SetToolTip(_L("Click to select filament color"));
+#ifdef __WXGTK__
+        RemoveButtonBorder(clr_picker);
+#endif
         clr_picker->Bind(wxEVT_BUTTON, [this](wxCommandEvent& e) {
             // Check if it's an official filament
             auto fila_type = Preset::remove_suffix_modified(GetValue().ToUTF8().data());

src/slic3r/GUI/Widgets/CheckBox.cpp

@@ -2,7 +2,7 @@
 
 #include "../wxExtensions.hpp"
 
-#ifdef __WXGTK3__
+#ifdef __WXGTK__
 #include "../GUI_Utils.hpp"
 #endif
 
@@ -29,7 +29,7 @@ CheckBox::CheckBox(wxWindow *parent, int id)
     Bind(wxEVT_LEAVE_WINDOW, &CheckBox::updateBitmap, this);
 #endif
 
-#ifdef __WXGTK3__
+#ifdef __WXGTK__
     Slic3r::GUI::RemoveButtonBorder(this);
 #endif
 

src/slic3r/GUI/Widgets/RadioBox.cpp

@@ -2,6 +2,10 @@
 
 #include "../wxExtensions.hpp"
 
+#ifdef __WXGTK__
+#include "../GUI_Utils.hpp"
+#endif
+
 namespace Slic3r {
 namespace GUI {
 RadioBox::RadioBox(wxWindow *parent)
@@ -15,6 +19,7 @@ RadioBox::RadioBox(wxWindow *parent)
     // Bind(wxEVT_TOGGLEBUTTON, [this](auto& e) { update(); e.Skip(); });
     update();
 #ifdef __WXGTK__
+    Slic3r::GUI::RemoveButtonBorder(this);
     wxSize bestSize = GetBestSize();
     bestSize.IncTo(m_on.GetBmpSize());
     SetSize(bestSize);

src/slic3r/GUI/Widgets/SpinInput.cpp

@@ -5,6 +5,10 @@
 
 #include <wx/dcgraph.h>
 
+#ifdef __WXGTK__
+#include "../GUI_Utils.hpp"
+#endif
+
 BEGIN_EVENT_TABLE(SpinInput, StaticBox)
 
 EVT_KEY_DOWN(SpinInput::keyPressed)
@@ -58,6 +62,11 @@ void SpinInput::Create(wxWindow *parent,
     state_handler.attach({&label_color, &text_color});
     state_handler.update_binds();
     text_ctrl = new TextCtrl(this, wxID_ANY, text, {20, 4}, wxDefaultSize, style | wxBORDER_NONE | wxTE_PROCESS_ENTER, wxTextValidator(wxFILTER_DIGITS));
+
+#ifdef __WXGTK__
+    Slic3r::GUI::RemoveInputBorder(text_ctrl);
+#endif
+
     text_ctrl->SetFont(Label::Body_14);
     text_ctrl->SetBackgroundColour(background_color.colorForStates(state_handler.states()));
     text_ctrl->SetForegroundColour(text_color.colorForStates(state_handler.states()));

src/slic3r/GUI/Widgets/SwitchButton.cpp

@@ -12,7 +12,7 @@
 #include "libslic3r/MacUtils.hpp"
 #endif
 
-#ifdef __WXGTK3__
+#ifdef __WXGTK__
 #include "../GUI_Utils.hpp"
 #endif
 
@@ -37,7 +37,7 @@ SwitchButton::SwitchButton(wxWindow* parent, wxWindowID id)
 	Bind(wxEVT_TOGGLEBUTTON, [this](auto& e) { update(); e.Skip(); });
 	SetFont(Label::Body_12);
 
-#ifdef __WXGTK3__
+#ifdef __WXGTK__
     Slic3r::GUI::RemoveButtonBorder(this);
 #endif
 

src/slic3r/GUI/Widgets/TextInput.cpp

@@ -6,6 +6,10 @@
 #include <wx/dcclient.h>
 #include <wx/dcgraph.h>
 
+#ifdef __WXGTK__
+#include "../GUI_Utils.hpp"
+#endif
+
 BEGIN_EVENT_TABLE(TextInput, StaticBox)
 
 EVT_PAINT(TextInput::paintEvent)
@@ -60,6 +64,11 @@ void TextInput::Create(wxWindow *     parent,
     state_handler.attach({&label_color, & text_color});
     state_handler.update_binds();
     text_ctrl = new TextCtrl(this, wxID_ANY, text, {4, 4}, wxDefaultSize, style | wxBORDER_NONE | wxTE_PROCESS_ENTER);
+
+#ifdef __WXGTK__
+    Slic3r::GUI::RemoveInputBorder(text_ctrl);
+#endif
+
     text_ctrl->SetFont(Label::Body_14);
     text_ctrl->SetInitialSize(text_ctrl->GetBestSize());
     text_ctrl->SetBackgroundColour(background_color.colorForStates(state_handler.states()));

src/slic3r/GUI/wxExtensions.cpp

@@ -1022,6 +1022,10 @@ ScalableButton::ScalableButton( wxWindow *          parent,
         m_width = size.x * 10 / em;
         m_height= size.y * 10 / em;
     }
+
+#ifdef __WXGTK__
+    Slic3r::GUI::RemoveButtonBorder(this);
+#endif
 }