Fix Dark Mode issues on Linux(via LAB) (#5044)

* GUI_App.cpp: trailing whitespace cleanup

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>

* StateColor.hpp: trailing whitespace cleanup

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>

* implementing LAB color routines

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>

* Fixes 3667: light/dark fixes for Unsaved Changes dialog

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>

* Fixes: 3675 - set dark mode colors for tabs

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>

* GUI_App: use LAB for fallback and sanity checks

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>

---------

Signed-off-by: Jamin W. Collins <jamin.collins@gmail.com>
Co-authored-by: SoftFever <softfeverever@gmail.com>

src/slic3r/GUI/GUI_App.cpp

@@ -959,7 +959,7 @@ void GUI_App::post_init()
 
     if (app_config->get("stealth_mode") == "false")
         hms_query = new HMSQuery();
-    
+
     m_show_gcode_window = app_config->get_bool("show_gcode_window");
     if (m_networking_need_update) {
         //updating networking
@@ -2807,7 +2807,7 @@ void GUI_App::init_label_colours()
     m_color_label_modified = is_dark_mode ? wxColour("#F1754E") : wxColour("#F1754E");
     m_color_label_sys      = is_dark_mode ? wxColour("#B2B3B5") : wxColour("#363636");
 
-#ifdef _WIN32
+#if defined(_WIN32) || defined(__linux__) || defined(__APPLE__)
     m_color_label_default           = is_dark_mode ? wxColour(250, 250, 250) : m_color_label_sys; // wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOWTEXT);
     m_color_highlight_label_default = is_dark_mode ? wxColour(230, 230, 230): wxSystemSettings::GetColour(/*wxSYS_COLOUR_HIGHLIGHTTEXT*/wxSYS_COLOUR_WINDOWTEXT);
     m_color_highlight_default       = is_dark_mode ? wxColour(78, 78, 78)   : wxSystemSettings::GetColour(wxSYS_COLOUR_3DLIGHT);
@@ -2920,22 +2920,38 @@ void GUI_App::UpdateDarkUI(wxWindow* window, bool highlited/* = false*/, bool ju
 
     /*if (m_is_dark_mode != dark_mode() )
         m_is_dark_mode = dark_mode();*/
-    
 
     if (m_is_dark_mode) {
-        auto original_col = window->GetBackgroundColour();
-        auto bg_col = StateColor::darkModeColorFor(original_col);
 
-        if (bg_col != original_col) {
+        auto orig_col = window->GetBackgroundColour();
+        auto bg_col = StateColor::darkModeColorFor(orig_col);
+        // there are cases where the background color of an item is bright, specifically:
+        // * the background color of a button: #009688  -- 73
+        if (bg_col != orig_col) {
             window->SetBackgroundColour(bg_col);
         }
 
-        original_col = window->GetForegroundColour();
+        orig_col = window->GetForegroundColour();
-        auto fg_col = StateColor::darkModeColorFor(original_col);
+        auto fg_col = StateColor::darkModeColorFor(orig_col);
+        auto fg_l = StateColor::GetLightness(fg_col);
 
-        if (fg_col != original_col) {
+        auto color_difference = StateColor::GetColorDifference(bg_col, fg_col);
-            window->SetForegroundColour(fg_col);
+
+        // fallback and sanity check with LAB
+        // color difference of less than 2 or 3 is not normally visible, and even less than 30-40 doesn't stand out
+        if (color_difference < 10) {
+            fg_col = StateColor::SetLightness(fg_col, 90);
         }
+        // some of the stock colors have a lightness of ~49
+        if (fg_l < 45) {
+            fg_col = StateColor::SetLightness(fg_col, 70);
+        }
+        // at this point it shouldn't be possible that fg_col is the same as bg_col, but let's be safe
+        if (fg_col == bg_col) {
+            fg_col = StateColor::SetLightness(fg_col, 70);
+        }
+
+        window->SetForegroundColour(fg_col);
     }
     else {
         auto original_col = window->GetBackgroundColour();
@@ -3891,7 +3907,7 @@ void GUI_App::on_http_error(wxCommandEvent &evt)
         MessageDialog msg_dlg(nullptr, _L("The version of Orca Slicer is too low and needs to be updated to the latest version before it can be used normally"), "", wxAPPLY | wxOK);
         if (msg_dlg.ShowModal() == wxOK) {
         }
-       
+
     }
 
     // request login

src/slic3r/GUI/UnsavedChangesDialog.cpp

@@ -1533,7 +1533,6 @@ void UnsavedChangesDialog::update_list()
                      text_left->SetFont(::Label::Head_13);
                      text_left->Wrap(-1);
                      text_left->SetForegroundColour(GREY700);
-                     text_left->SetForegroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_INFOTEXT));
 
                      sizer_left_v->Add(text_left, 0, wxLEFT, 37);
 
@@ -1562,7 +1561,6 @@ void UnsavedChangesDialog::update_list()
                 text_left->SetFont(::Label::Body_13);
                 text_left->Wrap(-1);
                 text_left->SetForegroundColour(GREY700);
-                text_left->SetForegroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_INFOTEXT));
 
                 sizer_left_v->Add(text_left, 0, wxLEFT, 51 );
 

src/slic3r/GUI/Widgets/StateColor.cpp

@@ -1,4 +1,5 @@
 #include "StateColor.hpp"
+#include <cmath>
 
 static bool gDarkMode = false;
 
@@ -41,7 +42,136 @@ static std::map<wxColour, wxColour> gDarkColors{
     //{"#F0F0F0", "#4C4C54"},
 };
 
-std::map<wxColour, wxColour> const & StateColor::GetDarkMap() 
+std::tuple<double, double, double> StateColor::GetLAB(const wxColour& color) {
+    // Convert color to RGB color space
+    double r = color.Red() / 255.0;
+    double g = color.Green() / 255.0;
+    double b = color.Blue() / 255.0;
+
+    // Convert to XYZ color space
+    double x = 0.412453*r + 0.357580*g + 0.180423*b;
+    double y = 0.212671*r + 0.715160*g + 0.072169*b;
+    double z = 0.019334*r + 0.119193*g + 0.950227*b;
+
+    // Normalize XYZ values
+    double x_n = x / 0.950456;
+    double y_n = y / 1.0;
+    double z_n = z / 1.088754;
+
+    // Convert to LAB color space
+    double epsilon = 0.008856;
+    double kappa = 903.3;
+    double fx = (x_n > epsilon) ? cbrt(x_n) : (kappa*x_n + 16.0) / 116.0;
+    double fy = (y_n > epsilon) ? cbrt(y_n) : (kappa*y_n + 16.0) / 116.0;
+    double fz = (z_n > epsilon) ? cbrt(z_n) : (kappa*z_n + 16.0) / 116.0;
+
+    double l = 116.0 * fy - 16.0;
+    double a = 500.0 * (fx - fy);
+    double b_lab = 200.0 * (fy - fz);
+
+    return std::tuple<double, double, double>(l, a, b_lab);
+}
+
+double StateColor::LAB_Delta_E(const wxColour& color1, const wxColour& color2) {
+    auto [l1, a1, b1] = GetLAB(color1);
+    auto [l2, a2, b2] = GetLAB(color2);
+    return sqrt((l1 - l2) * (l1 - l2) + (a1 - a2) * (a1 - a2) + (b1 - b2) * (b1 - b2));
+}
+
+double StateColor::GetColorDifference(const wxColour& color1, const wxColour& color2) {
+    return LAB_Delta_E(color1, color2);
+}
+
+double StateColor::GetLightness(const wxColour& color) {
+    auto [l, a, b_lab] = GetLAB(color);
+    return l;
+}
+
+// Function to lighten or darken a wxColour using LAB color space
+wxColour StateColor::SetLightness(const wxColour& color, double lightness) {
+    auto [l, a, b_lab] = GetLAB(color);
+
+    // Clamp lightness value
+    l = std::max(0.0, std::min(100.0, lightness));
+
+    // Convert back to XYZ color space
+    double fy_3 = (l + 16.0) / 116.0;
+    double fx_3 = a / 500.0 + fy_3;
+    double fz_3 = fy_3 - b_lab / 200.0;
+
+    double epsilon = 0.008856;
+    double kappa = 903.3;
+    double x_3 = (fx_3 > epsilon) ? fx_3 * fx_3 * fx_3 : (116.0 * fx_3 - 16.0) / kappa;
+    double y_3 = (l > kappa*epsilon) ? fy_3 * fy_3 * fy_3 : l / kappa;
+    double z_3 = (fz_3 > epsilon) ? fz_3 * fz_3 * fz_3 : (116.0 * fz_3 - 16.0) / kappa;
+
+    // Denormalize XYZ values
+    double x = x_3 * 0.950456;
+    double y = y_3 * 1.0;
+    double z = z_3 * 1.088754;
+
+    // Convert XYZ to RGB
+    double r_new = 3.240479*x - 1.537150*y - 0.498535*z;
+    double g_new = -0.969256*x + 1.875992*y + 0.041556*z;
+    double b_new = 0.055648*x - 0.204043*y + 1.057311*z;
+
+    // Clamp RGB values
+    r_new = std::max(0.0, std::min(1.0, r_new));
+    g_new = std::max(0.0, std::min(1.0, g_new));
+    b_new = std::max(0.0, std::min(1.0, b_new));
+
+    // Convert back to wxColour
+    int r_int = static_cast<int>(r_new * 255);
+    int g_int = static_cast<int>(g_new * 255);
+    int b_int = static_cast<int>(b_new * 255);
+
+    return wxColour(r_int, g_int, b_int);
+}
+
+wxColour StateColor::LightenDarkenColor(const wxColour& color, int amount) {
+    auto [l, a, b_lab] = GetLAB(color);
+
+    // Modify lightness
+    l += amount;
+
+    // Clamp lightness value
+    l = std::max(0.0, std::min(100.0, l));
+
+    // Convert back to XYZ color space
+    double fy_3 = (l + 16.0) / 116.0;
+    double fx_3 = a / 500.0 + fy_3;
+    double fz_3 = fy_3 - b_lab / 200.0;
+
+    double epsilon = 0.008856;
+    double kappa = 903.3;
+    double x_3 = (fx_3 > epsilon) ? fx_3 * fx_3 * fx_3 : (116.0 * fx_3 - 16.0) / kappa;
+    double y_3 = (l > kappa*epsilon) ? fy_3 * fy_3 * fy_3 : l / kappa;
+    double z_3 = (fz_3 > epsilon) ? fz_3 * fz_3 * fz_3 : (116.0 * fz_3 - 16.0) / kappa;
+
+    // Denormalize XYZ values
+    double x = x_3 * 0.950456;
+    double y = y_3 * 1.0;
+    double z = z_3 * 1.088754;
+
+    // Convert XYZ to RGB
+    double r_new = 3.240479*x - 1.537150*y - 0.498535*z;
+    double g_new = -0.969256*x + 1.875992*y + 0.041556*z;
+    double b_new = 0.055648*x - 0.204043*y + 1.057311*z;
+
+    // Clamp RGB values
+    r_new = std::max(0.0, std::min(1.0, r_new));
+    g_new = std::max(0.0, std::min(1.0, g_new));
+    b_new = std::max(0.0, std::min(1.0, b_new));
+
+    // Convert back to wxColour
+    int r_int = static_cast<int>(r_new * 255);
+    int g_int = static_cast<int>(g_new * 255);
+    int b_int = static_cast<int>(b_new * 255);
+
+    return wxColour(r_int, g_int, b_int);
+}
+
+std::map<wxColour, wxColour> const & StateColor::GetDarkMap()
 {
     return gDarkColors;
 }

src/slic3r/GUI/Widgets/StateColor.hpp

@@ -9,7 +9,7 @@ class StateColor
 {
 public:
     enum State {
-        Normal = 0, 
+        Normal = 0,
         Enabled = 1,
         Checked = 2,
         Focused = 4,
@@ -23,6 +23,13 @@ public:
     };
 
 public:
+    static std::tuple<double, double, double> GetLAB(const wxColour& color);
+    static double GetLightness(const wxColour& color);
+    static wxColour SetLightness(const wxColour& color, double lightness);
+    static wxColour LightenDarkenColor(const wxColour& color, int amount);
+    static double GetColorDifference(const wxColour& c1, const wxColour& c2);
+    static double LAB_Delta_E(const wxColour& c1, const wxColour& c2);
+
     static void SetDarkMode(bool dark);
 
     static std::map<wxColour, wxColour> const & GetDarkMap();