Implement lv2ui background/foreground color

Signed-off-by: falkTX <falktx@falktx.com>

source/backend/CarlaBackend.h

@@ -1357,51 +1357,61 @@ typedef enum {
     ENGINE_OPTION_PREVENT_BAD_BEHAVIOUR = 22,
 
     /*!
-     * Set UI scaling used in frontend, so backend can do the same for plugin UIs.
+     * Set background color used in the frontend, so backend can do the same for plugin UIs.
      */
-    ENGINE_OPTION_FRONTEND_UI_SCALE = 23,
+    ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR = 23,
+
+    /*!
+     * Set foreground color used in the frontend, so backend can do the same for plugin UIs.
+     */
+    ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR = 24,
+
+    /*!
+     * Set UI scaling used in the frontend, so backend can do the same for plugin UIs.
+     */
+    ENGINE_OPTION_FRONTEND_UI_SCALE = 25,
 
     /*!
      * Set frontend winId, used to define as parent window for plugin UIs.
      */
-    ENGINE_OPTION_FRONTEND_WIN_ID = 24,
+    ENGINE_OPTION_FRONTEND_WIN_ID = 26,
 
 #if !defined(BUILD_BRIDGE_ALTERNATIVE_ARCH) && !defined(CARLA_OS_WIN)
     /*!
      * Set path to wine executable.
      */
-    ENGINE_OPTION_WINE_EXECUTABLE = 25,
+    ENGINE_OPTION_WINE_EXECUTABLE = 27,
 
     /*!
      * Enable automatic wineprefix detection.
      */
-    ENGINE_OPTION_WINE_AUTO_PREFIX = 26,
+    ENGINE_OPTION_WINE_AUTO_PREFIX = 28,
 
     /*!
      * Fallback wineprefix to use if automatic detection fails or is disabled, and WINEPREFIX is not set.
      */
-    ENGINE_OPTION_WINE_FALLBACK_PREFIX = 27,
+    ENGINE_OPTION_WINE_FALLBACK_PREFIX = 29,
 
     /*!
      * Enable realtime priority for Wine application and server threads.
      */
-    ENGINE_OPTION_WINE_RT_PRIO_ENABLED = 28,
+    ENGINE_OPTION_WINE_RT_PRIO_ENABLED = 30,
 
     /*!
      * Base realtime priority for Wine threads.
      */
-    ENGINE_OPTION_WINE_BASE_RT_PRIO = 29,
+    ENGINE_OPTION_WINE_BASE_RT_PRIO = 31,
 
     /*!
      * Wine server realtime priority.
      */
-    ENGINE_OPTION_WINE_SERVER_RT_PRIO = 30,
+    ENGINE_OPTION_WINE_SERVER_RT_PRIO = 32,
 #endif
 
     /*!
      * Capture console output into debug callbacks.
      */
-    ENGINE_OPTION_DEBUG_CONSOLE_OUTPUT = 31
+    ENGINE_OPTION_DEBUG_CONSOLE_OUTPUT = 33
 
 } EngineOption;
 

source/backend/CarlaEngine.hpp

@@ -239,6 +239,8 @@ struct CARLA_API EngineOptions {
     bool preferPluginBridges;
     bool preferUiBridges;
     bool uisAlwaysOnTop;
+    uint bgColor;
+    uint fgColor;
     float uiScale;
 
     uint maxParameters;

source/backend/CarlaStandalone.cpp

@@ -312,6 +312,8 @@ static void carla_engine_init_common(CarlaEngine* const engine)
 
     engine->setOption(CB::ENGINE_OPTION_PREVENT_BAD_BEHAVIOUR,    gStandalone.engineOptions.preventBadBehaviour ? 1 : 0,  nullptr);
 
+    engine->setOption(CB::ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR, static_cast<int>(gStandalone.engineOptions.bgColor), nullptr);
+    engine->setOption(CB::ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR, static_cast<int>(gStandalone.engineOptions.fgColor), nullptr);
     engine->setOption(CB::ENGINE_OPTION_FRONTEND_UI_SCALE, static_cast<int>(gStandalone.engineOptions.uiScale * 1000.0f), nullptr);
 
     if (gStandalone.engineOptions.frontendWinId != 0)
@@ -848,6 +850,14 @@ void carla_set_engine_option(EngineOption option, int value, const char* valueSt
         gStandalone.engineOptions.preventBadBehaviour = (value != 0);
         break;
 
+    case CB::ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR:
+        gStandalone.engineOptions.bgColor = static_cast<uint>(value);
+        break;
+
+    case CB::ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR:
+        gStandalone.engineOptions.fgColor = static_cast<uint>(value);
+        break;
+
     case CB::ENGINE_OPTION_FRONTEND_UI_SCALE:
         CARLA_SAFE_ASSERT_RETURN(value > 0,);
         gStandalone.engineOptions.uiScale = static_cast<float>(value) / 1000;

source/backend/engine/CarlaEngine.cpp

@@ -1901,6 +1901,14 @@ void CarlaEngine::setOption(const EngineOption option, const int value, const ch
 #endif
     }   break;
 
+    case ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR:
+        pData->options.bgColor = static_cast<uint>(value);
+        break;
+
+    case ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR:
+        pData->options.fgColor = static_cast<uint>(value);
+        break;
+
     case ENGINE_OPTION_FRONTEND_UI_SCALE:
         CARLA_SAFE_ASSERT_RETURN(value > 0,);
         pData->options.uiScale = static_cast<float>(value) / 1000;

source/backend/engine/CarlaEngineData.cpp

@@ -192,6 +192,8 @@ EngineOptions::EngineOptions() noexcept
       preferUiBridges(true),
 #endif
       uisAlwaysOnTop(true),
+      bgColor(0x000000ff),
+      fgColor(0xffffffff),
       uiScale(1.0f),
       maxParameters(MAX_DEFAULT_PARAMETERS),
       uiBridgesTimeout(4000),

source/backend/plugin/CarlaPluginLV2.cpp

@@ -132,11 +132,16 @@ enum CarlaLv2URIDs {
     kUridTimeTicksPerBeat,
     kUridMidiEvent,
     kUridParamSampleRate,
+    // ui stuff
+    kUridBackgroundColor,
+    kUridForegroundColor,
     kUridScaleFactor,
     kUridWindowTitle,
+    // custom carla props
     kUridCarlaAtomWorkerIn,
     kUridCarlaAtomWorkerResp,
     kUridCarlaTransientWindowId,
+    // count
     kUridCount
 };
 
@@ -316,6 +321,8 @@ struct CarlaPluginLV2Options {
         SequenceSize,
         SampleRate,
         TransientWinId,
+        BackgroundColor,
+        ForegroundColor,
         ScaleFactor,
         WindowTitle,
         Null,
@@ -328,6 +335,8 @@ struct CarlaPluginLV2Options {
     int sequenceSize;
     float sampleRate;
     int64_t transientWinId;
+    uint32_t bgColor;
+    uint32_t fgColor;
     float uiScale;
     const char* windowTitle;
     LV2_Options_Option opts[Count];
@@ -339,6 +348,8 @@ struct CarlaPluginLV2Options {
           sequenceSize(MAX_DEFAULT_BUFFER_SIZE),
           sampleRate(0.0),
           transientWinId(0),
+          bgColor(0x000000ff),
+          fgColor(0xffffffff),
           uiScale(1.0f),
           windowTitle(nullptr)
     {
@@ -374,6 +385,22 @@ struct CarlaPluginLV2Options {
         optSequenceSize.type    = kUridAtomInt;
         optSequenceSize.value   = &sequenceSize;
 
+        LV2_Options_Option& optBackgroundColor(opts[BackgroundColor]);
+        optBackgroundColor.context = LV2_OPTIONS_INSTANCE;
+        optBackgroundColor.subject = 0;
+        optBackgroundColor.key     = kUridBackgroundColor;
+        optBackgroundColor.size    = sizeof(int32_t);
+        optBackgroundColor.type    = kUridAtomInt;
+        optBackgroundColor.value   = &bgColor;
+
+        LV2_Options_Option& optForegroundColor(opts[ForegroundColor]);
+        optForegroundColor.context = LV2_OPTIONS_INSTANCE;
+        optForegroundColor.subject = 0;
+        optForegroundColor.key     = kUridForegroundColor;
+        optForegroundColor.size    = sizeof(int32_t);
+        optForegroundColor.type    = kUridAtomInt;
+        optForegroundColor.value   = &fgColor;
+
         LV2_Options_Option& optScaleFactor(opts[ScaleFactor]);
         optScaleFactor.context = LV2_OPTIONS_INSTANCE;
         optScaleFactor.subject = 0;
@@ -1576,11 +1603,21 @@ public:
                     if (! fPipeServer.writeMessage("uiOptions\n", 10))
                         return;
 
+                    const EngineOptions& opts(pData->engine->getOptions());
+
                     std::snprintf(tmpBuf, 0xff, "%g\n", pData->engine->getSampleRate());
                     if (! fPipeServer.writeMessage(tmpBuf))
                         return;
 
-                    std::snprintf(tmpBuf, 0xff, "%.12g\n", static_cast<double>(pData->engine->getOptions().uiScale));
+                    std::snprintf(tmpBuf, 0xff, "%u\n", opts.bgColor);
+                    if (! fPipeServer.writeMessage(tmpBuf))
+                        return;
+
+                    std::snprintf(tmpBuf, 0xff, "%u\n", opts.fgColor);
+                    if (! fPipeServer.writeMessage(tmpBuf))
+                        return;
+
+                    std::snprintf(tmpBuf, 0xff, "%.12g\n", static_cast<double>(opts.uiScale));
                     if (! fPipeServer.writeMessage(tmpBuf))
                         return;
 
@@ -5541,13 +5578,15 @@ public:
             return false;
         }
 
+        const EngineOptions& opts(pData->engine->getOptions());
+
         // ---------------------------------------------------------------
         // Init LV2 World if needed, sets LV2_PATH for lilv
 
         Lv2WorldClass& lv2World(Lv2WorldClass::getInstance());
 
-        if (pData->engine->getOptions().pathLV2 != nullptr && pData->engine->getOptions().pathLV2[0] != '\0')
-            lv2World.initIfNeeded(pData->engine->getOptions().pathLV2);
+        if (opts.pathLV2 != nullptr && opts.pathLV2[0] != '\0')
+            lv2World.initIfNeeded(opts.pathLV2);
         else if (const char* const LV2_PATH = std::getenv("LV2_PATH"))
             lv2World.initIfNeeded(LV2_PATH);
         else
@@ -5725,7 +5764,7 @@ public:
         fLv2Options.maxBufferSize     = bufferSize;
         fLv2Options.nominalBufferSize = bufferSize;
         fLv2Options.sampleRate        = static_cast<float>(pData->engine->getSampleRate());
-        fLv2Options.transientWinId    = static_cast<int64_t>(pData->engine->getOptions().frontendWinId);
+        fLv2Options.transientWinId    = static_cast<int64_t>(opts.frontendWinId);
 
         uint32_t eventBufferSize = MAX_DEFAULT_BUFFER_SIZE;
 
@@ -5742,7 +5781,9 @@ public:
 
         fLv2Options.sequenceSize = static_cast<int>(eventBufferSize);
 
-        fLv2Options.uiScale = pData->engine->getOptions().uiScale;
+        fLv2Options.bgColor = opts.bgColor;
+        fLv2Options.fgColor = opts.fgColor;
+        fLv2Options.uiScale = opts.uiScale;
 
         // ---------------------------------------------------------------
         // initialize features (part 1)
@@ -5903,7 +5944,7 @@ public:
         else if (options & PLUGIN_OPTION_FIXED_BUFFERS)
             pData->options |= PLUGIN_OPTION_FIXED_BUFFERS;
 
-        if (pData->engine->getOptions().forceStereo)
+        if (opts.forceStereo)
             pData->options |= PLUGIN_OPTION_FORCE_STEREO;
         else if (options & PLUGIN_OPTION_FORCE_STEREO)
             pData->options |= PLUGIN_OPTION_FORCE_STEREO;
@@ -6816,6 +6857,10 @@ private:
             return kUridMidiEvent;
         if (std::strcmp(uri, LV2_PARAMETERS__sampleRate) == 0)
             return kUridParamSampleRate;
+        if (std::strcmp(uri, LV2_UI__backgroundColor) == 0)
+            return kUridBackgroundColor;
+        if (std::strcmp(uri, LV2_UI__foregroundColor) == 0)
+            return kUridForegroundColor;
         if (std::strcmp(uri, LV2_UI__scaleFactor) == 0)
             return kUridScaleFactor;
         if (std::strcmp(uri, LV2_UI__windowTitle) == 0)
@@ -6946,6 +6991,10 @@ private:
             return LV2_MIDI__MidiEvent;
         case kUridParamSampleRate:
             return LV2_PARAMETERS__sampleRate;
+        case kUridBackgroundColor:
+            return LV2_UI__backgroundColor;
+        case kUridForegroundColor:
+            return LV2_UI__foregroundColor;
         case kUridScaleFactor:
             return LV2_UI__scaleFactor;
         case kUridWindowTitle:

source/bridges-ui/CarlaBridgeFormat.cpp

@@ -226,25 +226,21 @@ bool CarlaBridgeFormat::msgReceived(const char* const msg) noexcept
 
     if (std::strcmp(msg, "uiOptions") == 0)
     {
-        double sampleRate;
-        bool useTheme, useThemeColors;
-        float uiScale;
-        const char* windowTitle;
-        uint64_t transientWindowId;
-
-        CARLA_SAFE_ASSERT_RETURN(readNextLineAsDouble(sampleRate), true);
-        CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(uiScale), true);
-        CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(useTheme), true);
-        CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(useThemeColors), true);
-        CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(windowTitle), true);
-        CARLA_SAFE_ASSERT_RETURN(readNextLineAsULong(transientWindowId), true);
+        BridgeFormatOptions opts;
+
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsDouble(opts.sampleRate), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(opts.bgColor), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(opts.fgColor), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(opts.uiScale), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(opts.useTheme), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(opts.useThemeColors), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(opts.windowTitle), true);
+        CARLA_SAFE_ASSERT_RETURN(readNextLineAsULong(opts.transientWindowId), true);
 
         fGotOptions = true;
-        uiOptionsChanged(sampleRate, uiScale,
-                         useTheme, useThemeColors,
-                         windowTitle, static_cast<uintptr_t>(transientWindowId));
+        uiOptionsChanged(opts);
 
-        delete[] windowTitle;
+        delete[] opts.windowTitle;
         return true;
     }
 

source/bridges-ui/CarlaBridgeFormat.hpp

@@ -69,9 +69,18 @@ protected:
     virtual void dspAtomReceived(const uint32_t index, const LV2_Atom* const atom) = 0;
     virtual void dspURIDReceived(const LV2_URID urid, const char* const uri) = 0;
 
-    virtual void uiOptionsChanged(const double sampleRate, const float uiScale,
-                                  const bool useTheme, const bool useThemeColors,
-                                  const char* const windowTitle, const uintptr_t transientWindowId) = 0;
+    struct BridgeFormatOptions {
+        double sampleRate;
+        uint32_t bgColor;
+        uint32_t fgColor;
+        float uiScale;
+        bool useTheme;
+        bool useThemeColors;
+        const char* windowTitle;
+        uintptr_t transientWindowId;
+    };
+
+    virtual void uiOptionsChanged(const BridgeFormatOptions& opts) = 0;
 
 public:
     // ---------------------------------------------------------------------

source/bridges-ui/CarlaBridgeFormatLV2.cpp

@@ -93,11 +93,16 @@ enum CarlaLv2URIDs {
     kUridTimeTicksPerBeat,
     kUridMidiEvent,
     kUridParamSampleRate,
+    // ui stuff
+    kUridBackgroundColor,
+    kUridForegroundColor,
     kUridScaleFactor,
     kUridWindowTitle,
+    // custom carla props
     kUridCarlaAtomWorkerIn,
     kUridCarlaAtomWorkerResp,
     kUridCarlaTransientWindowId,
+    // count
     kUridCount
 };
 
@@ -131,6 +136,8 @@ struct Lv2PluginOptions {
     enum OptIndex {
         SampleRate,
         TransientWinId,
+        BackgroundColor,
+        ForegroundColor,
         ScaleFactor,
         WindowTitle,
         Null,
@@ -139,12 +146,16 @@ struct Lv2PluginOptions {
 
     float sampleRate;
     int64_t transientWinId;
+    uint32_t bgColor;
+    uint32_t fgColor;
     float uiScale;
     LV2_Options_Option opts[Count];
 
     Lv2PluginOptions() noexcept
         : sampleRate(static_cast<float>(gInitialSampleRate)),
           transientWinId(0),
+          bgColor(0x000000ff),
+          fgColor(0xffffffff),
           uiScale(1.0f)
     {
         LV2_Options_Option& optSampleRate(opts[SampleRate]);
@@ -155,6 +166,22 @@ struct Lv2PluginOptions {
         optSampleRate.type    = kUridAtomFloat;
         optSampleRate.value   = &sampleRate;
 
+        LV2_Options_Option& optBackgroundColor(opts[BackgroundColor]);
+        optBackgroundColor.context = LV2_OPTIONS_INSTANCE;
+        optBackgroundColor.subject = 0;
+        optBackgroundColor.key     = kUridBackgroundColor;
+        optBackgroundColor.size    = sizeof(int32_t);
+        optBackgroundColor.type    = kUridAtomInt;
+        optBackgroundColor.value   = &bgColor;
+
+        LV2_Options_Option& optForegroundColor(opts[ForegroundColor]);
+        optForegroundColor.context = LV2_OPTIONS_INSTANCE;
+        optForegroundColor.subject = 0;
+        optForegroundColor.key     = kUridForegroundColor;
+        optForegroundColor.size    = sizeof(int32_t);
+        optForegroundColor.type    = kUridAtomInt;
+        optForegroundColor.value   = &fgColor;
+
         LV2_Options_Option& optScaleFactor(opts[ScaleFactor]);
         optScaleFactor.context = LV2_OPTIONS_INSTANCE;
         optScaleFactor.subject = 0;
@@ -598,19 +625,14 @@ public:
         fCustomURIDs.push_back(uri);
     }
 
-    void uiOptionsChanged(const double sampleRate, const float uiScale,
-                          const bool useTheme, const bool useThemeColors,
-                          const char* const windowTitle, const uintptr_t transientWindowId) override
+    void uiOptionsChanged(const BridgeFormatOptions& opts) override
     {
-        carla_debug("CarlaLv2Client::uiOptionsChanged(%f, %f, %s, %s, \"%s\", " P_UINTPTR ")",
-                    sampleRate, static_cast<double>(uiScale),
-                    bool2str(useTheme), bool2str(useThemeColors),
-                    windowTitle, transientWindowId);
+        carla_debug("CarlaLv2Client::uiOptionsChanged()");
 
         // ------------------------------------------------------------------------------------------------------------
         // sample rate
 
-        const float sampleRatef = static_cast<float>(sampleRate);
+        const float sampleRatef = static_cast<float>(opts.sampleRate);
 
         if (carla_isNotEqual(fLv2Options.sampleRate, sampleRatef))
         {
@@ -634,15 +656,17 @@ public:
         }
 
         // ------------------------------------------------------------------------------------------------------------
-        // ui scale
+        // ui colors and scale
 
-        fLv2Options.uiScale = uiScale;
+        fLv2Options.bgColor = opts.bgColor;
+        fLv2Options.fgColor = opts.fgColor;
+        fLv2Options.uiScale = opts.uiScale;
 
         // ------------------------------------------------------------------------------------------------------------
         // window title
 
-        if (windowTitle != nullptr)
-            fUiOptions.windowTitle = windowTitle;
+        if (opts.windowTitle != nullptr)
+            fUiOptions.windowTitle = opts.windowTitle;
         else
             fUiOptions.windowTitle.clear();
 
@@ -652,14 +676,14 @@ public:
         // ------------------------------------------------------------------------------------------------------------
         // transient win id
 
-        fLv2Options.transientWinId = static_cast<int64_t>(transientWindowId);
-        fUiOptions.transientWindowId = transientWindowId;
+        fLv2Options.transientWinId = static_cast<int64_t>(opts.transientWindowId);
+        fUiOptions.transientWindowId = opts.transientWindowId;
 
         // ------------------------------------------------------------------------------------------------------------
         // other
 
-        fUiOptions.useTheme       = useTheme;
-        fUiOptions.useThemeColors = useThemeColors;
+        fUiOptions.useTheme       = opts.useTheme;
+        fUiOptions.useThemeColors = opts.useThemeColors;
     }
 
     void uiResized(const uint width, const uint height) override
@@ -1060,6 +1084,10 @@ private:
             return kUridMidiEvent;
         if (std::strcmp(uri, LV2_PARAMETERS__sampleRate) == 0)
             return kUridParamSampleRate;
+        if (std::strcmp(uri, LV2_UI__backgroundColor) == 0)
+            return kUridBackgroundColor;
+        if (std::strcmp(uri, LV2_UI__foregroundColor) == 0)
+            return kUridForegroundColor;
         if (std::strcmp(uri, LV2_UI__scaleFactor) == 0)
             return kUridScaleFactor;
         if (std::strcmp(uri, LV2_UI__windowTitle) == 0)
@@ -1190,6 +1218,10 @@ private:
             return LV2_MIDI__MidiEvent;
         case kUridParamSampleRate:
             return LV2_PARAMETERS__sampleRate;
+        case kUridBackgroundColor:
+            return LV2_UI__backgroundColor;
+        case kUridForegroundColor:
+            return LV2_UI__foregroundColor;
         case kUridScaleFactor:
             return LV2_UI__scaleFactor;
         case kUridWindowTitle:

source/frontend/carla_backend.py

@@ -959,32 +959,38 @@ ENGINE_OPTION_PATH_RESOURCES = 21
 # @note: Linux only
 ENGINE_OPTION_PREVENT_BAD_BEHAVIOUR = 22
 
-# Set UI scaling used in frontend, so backend can do the same for plugin UIs.
-ENGINE_OPTION_FRONTEND_UI_SCALE = 23
+# Set background color used in the frontend, so backend can do the same for plugin UIs.
+ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR = 23
+
+# Set foreground color used in the frontend, so backend can do the same for plugin UIs.
+ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR = 24
+
+# Set UI scaling used in the frontend, so backend can do the same for plugin UIs.
+ENGINE_OPTION_FRONTEND_UI_SCALE = 25
 
 # Set frontend winId, used to define as parent window for plugin UIs.
-ENGINE_OPTION_FRONTEND_WIN_ID = 24
+ENGINE_OPTION_FRONTEND_WIN_ID = 26
 
 # Set path to wine executable.
-ENGINE_OPTION_WINE_EXECUTABLE = 25
+ENGINE_OPTION_WINE_EXECUTABLE = 27
 
 # Enable automatic wineprefix detection.
-ENGINE_OPTION_WINE_AUTO_PREFIX = 26
+ENGINE_OPTION_WINE_AUTO_PREFIX = 28
 
 # Fallback wineprefix to use if automatic detection fails or is disabled, and WINEPREFIX is not set.
-ENGINE_OPTION_WINE_FALLBACK_PREFIX = 27
+ENGINE_OPTION_WINE_FALLBACK_PREFIX = 29
 
 # Enable realtime priority for Wine application and server threads.
-ENGINE_OPTION_WINE_RT_PRIO_ENABLED = 28
+ENGINE_OPTION_WINE_RT_PRIO_ENABLED = 30
 
 # Base realtime priority for Wine threads.
-ENGINE_OPTION_WINE_BASE_RT_PRIO = 29
+ENGINE_OPTION_WINE_BASE_RT_PRIO = 31
 
 # Wine server realtime priority.
-ENGINE_OPTION_WINE_SERVER_RT_PRIO = 30
+ENGINE_OPTION_WINE_SERVER_RT_PRIO = 32
 
 # Capture console output into debug callbacks
-ENGINE_OPTION_DEBUG_CONSOLE_OUTPUT = 31
+ENGINE_OPTION_DEBUG_CONSOLE_OUTPUT = 33
 
 # ------------------------------------------------------------------------------------------------------------
 # Engine Process Mode

source/frontend/carla_host.py

@@ -2542,7 +2542,9 @@ class HostWindow(QMainWindow):
         else:
             value_fix = 1.5
 
-        bg_color = self.ui.rack.palette().window().color()
+        rack_pal = self.ui.rack.palette()
+        bg_color = rack_pal.window().color()
+        fg_color = rack_pal.text().color()
         bg_value = 1.0 - bg_color.blackF()
         if bg_value != 0.0 and bg_value < min_value:
             pad_color = bg_color.lighter(100*min_value/bg_value*value_fix)
@@ -2574,6 +2576,16 @@ class HostWindow(QMainWindow):
         self.ui.pad_right.setPalette(self.imgR_palette)
         self.ui.pad_right.setAutoFillBackground(True)
 
+        # qt's rgba is actually argb, so convert that
+        bg_color_value = bg_color.rgba()
+        bg_color_value = ((bg_color_value & 0xffffff) << 8) | (bg_color_value >> 24)
+
+        fg_color_value = fg_color.rgba()
+        fg_color_value = ((fg_color_value & 0xffffff) << 8) | (fg_color_value >> 24)
+
+        self.host.set_engine_option(ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR, bg_color_value, "")
+        self.host.set_engine_option(ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR, fg_color_value, "")
+
     # --------------------------------------------------------------------------------------------------------
     # paint event
 

source/includes/lv2/ui.h

@@ -45,8 +45,10 @@
 #define LV2_UI__UI               LV2_UI_PREFIX "UI"                ///< http://lv2plug.in/ns/extensions/ui#UI
 #define LV2_UI__WindowsUI        LV2_UI_PREFIX "WindowsUI"         ///< http://lv2plug.in/ns/extensions/ui#WindowsUI
 #define LV2_UI__X11UI            LV2_UI_PREFIX "X11UI"             ///< http://lv2plug.in/ns/extensions/ui#X11UI
+#define LV2_UI__backgroundColor  LV2_UI_PREFIX "backgroundColor"   ///< http://lv2plug.in/ns/extensions/ui#backgroundColor
 #define LV2_UI__binary           LV2_UI_PREFIX "binary"            ///< http://lv2plug.in/ns/extensions/ui#binary
 #define LV2_UI__fixedSize        LV2_UI_PREFIX "fixedSize"         ///< http://lv2plug.in/ns/extensions/ui#fixedSize
+#define LV2_UI__foregroundColor  LV2_UI_PREFIX "foregroundColor"   ///< http://lv2plug.in/ns/extensions/ui#foregroundColor
 #define LV2_UI__idleInterface    LV2_UI_PREFIX "idleInterface"     ///< http://lv2plug.in/ns/extensions/ui#idleInterface
 #define LV2_UI__noUserResize     LV2_UI_PREFIX "noUserResize"      ///< http://lv2plug.in/ns/extensions/ui#noUserResize
 #define LV2_UI__notifyType       LV2_UI_PREFIX "notifyType"        ///< http://lv2plug.in/ns/extensions/ui#notifyType

source/utils/CarlaBackendUtils.hpp

@@ -372,6 +372,10 @@ const char* EngineOption2Str(const EngineOption option) noexcept
         return "ENGINE_OPTION_PATH_RESOURCES";
     case ENGINE_OPTION_PREVENT_BAD_BEHAVIOUR:
         return "ENGINE_OPTION_PREVENT_BAD_BEHAVIOUR";
+    case ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR:
+        return "ENGINE_OPTION_FRONTEND_BACKGROUND_COLOR";
+    case ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR:
+        return "ENGINE_OPTION_FRONTEND_FOREGROUND_COLOR";
     case ENGINE_OPTION_FRONTEND_UI_SCALE:
         return "ENGINE_OPTION_FRONTEND_UI_SCALE";
     case ENGINE_OPTION_FRONTEND_WIN_ID: