feat(wallpaper): add support for solid color backgrounds

CONFIG.md

@@ -9,6 +9,7 @@ A ready-to-use starting config with all defaults is at [`example.toml`](example.
 Notification daemon toggle: use `[notification].enable_daemon` (documented in [`config/services.md`](config/services.md)).
 Weather location visibility toggle: use `[shell].show_location` (documented in [`config/shell.md`](config/shell.md)).
 Wallpaper automation: use `[wallpaper.automation]` (documented in [`config/wallpaper.md`](config/wallpaper.md)).
+Wallpaper single-color fallback/fill: use `[wallpaper].fill_color` (documented in [`config/wallpaper.md`](config/wallpaper.md)).
 
 ---
 

config/wallpaper.md

@@ -4,6 +4,7 @@
 [wallpaper]
 enabled             = true
 fill_mode           = "crop"    # center | crop | fit | stretch | repeat
+fill_color          = "#111111" # optional fallback/fill color; image wallpapers take priority
 transition          = ["fade", "wipe", "disc", "stripes", "zoom", "honeycomb"]
                                 # array of effects picked at random each transition
                                 # omit to use all effects
@@ -32,6 +33,8 @@ directory_dark  = "/home/user/Wallpapers/Vertical/Dark"
 
 The wallpaper picker panel lists images in `directory` as a grid of thumbnails. Selecting a monitor in the panel toolbar switches to that monitor's override directory (falling back to the base `directory`). Clicking a tile writes the path to `state.toml` and applies it immediately. Picking a wallpaper while **ALL** is selected applies it to every connected output.
 
+`fill_color` accepts hex colors (`#RGB`, `#RGBA`, `#RRGGBB`, `#RRGGBBAA`) or theme role names such as `surface` and `primary`. It is used behind image wallpapers, in uncovered areas for `center`/`fit`, and as the full wallpaper when no image path is selected.
+
 When automation is enabled, Noctalia picks one image from `directory` on the configured interval and applies it to all connected outputs in sync.
 `order = "random"` chooses a random image each cycle.
 `order = "alphabetical"` sorts paths case-insensitively and advances to the next image each cycle (wrapping at the end).

example.toml

@@ -31,6 +31,7 @@ alpha    = 0.55                     # multiplied by each component's background
 [wallpaper]
 enabled             = true
 fill_mode           = "crop"        # center | crop | fit | stretch | repeat
+fill_color          = ""            # optional fallback/fill color: #RRGGBB, #RRGGBBAA, or theme role
 transition          = ["fade", "wipe", "disc", "stripes", "zoom", "honeycomb"]
 transition_duration = 1500          # milliseconds
 edge_smoothness     = 0.3

src/config/config_service.cpp

@@ -243,7 +243,12 @@ namespace {
   constexpr Logger kLog("config");
 
   ThemeColor themeColorFromRoleString(const std::string& raw) {
-    if (auto role = colorRoleFromToken(raw)) {
+    const std::string trimmed = StringUtils::trim(raw);
+    Color fixed;
+    if (tryParseHexColor(trimmed, fixed)) {
+      return fixedColor(fixed);
+    }
+    if (auto role = colorRoleFromToken(trimmed)) {
       return roleColor(*role);
     }
     kLog.warn("unknown theme color role \"{}\", using surface_variant", raw);
@@ -1357,6 +1362,13 @@ void ConfigService::parseTable(const toml::table& tbl) {
       else if (*v == "repeat")
         wp.fillMode = WallpaperFillMode::Repeat;
     }
+    if (auto v = (*wpTbl)["fill_color"].value<std::string>()) {
+      if (StringUtils::trim(*v).empty()) {
+        wp.fillColor = std::nullopt;
+      } else {
+        wp.fillColor = themeColorFromConfigString(*v);
+      }
+    }
     auto parseTransition = [](const std::string& s) -> std::optional<WallpaperTransition> {
       if (s == "fade")
         return WallpaperTransition::Fade;

src/config/config_service.h

@@ -183,6 +183,7 @@ struct WallpaperAutomationConfig {
 struct WallpaperConfig {
   bool enabled = true;
   WallpaperFillMode fillMode = WallpaperFillMode::Crop;
+  std::optional<ThemeColor> fillColor;
   std::vector<WallpaperTransition> transitions = {WallpaperTransition::Fade, WallpaperTransition::Wipe,
                                                   WallpaperTransition::Disc, WallpaperTransition::Stripes,
                                                   WallpaperTransition::Zoom, WallpaperTransition::Honeycomb};

src/render/programs/wallpaper_program.cpp

@@ -375,7 +375,7 @@ void WallpaperProgram::initProgram(std::size_t index, const char* fragSource) {
 void WallpaperProgram::draw(WallpaperTransition type, GLuint texture1, GLuint texture2, float surfaceWidth,
                             float surfaceHeight, float quadWidth, float quadHeight, float imageWidth1,
                             float imageHeight1, float imageWidth2, float imageHeight2, float progress, float fillMode,
-                            const TransitionParams& params, const Mat3& transform) const {
+                            const TransitionParams& params, const Color& fillColor, const Mat3& transform) const {
   auto idx = static_cast<std::size_t>(type);
   if (idx >= kTransitionCount || !m_programs[idx].program.isValid() || texture1 == 0 || quadWidth <= 0.0f ||
       quadHeight <= 0.0f) {
@@ -421,7 +421,7 @@ void WallpaperProgram::draw(WallpaperTransition type, GLuint texture1, GLuint te
   if (pd.screenHeightLoc >= 0)
     glUniform1f(pd.screenHeightLoc, quadHeight);
   if (pd.fillColorLoc >= 0)
-    glUniform4f(pd.fillColorLoc, 0.0f, 0.0f, 0.0f, 1.0f);
+    glUniform4f(pd.fillColorLoc, fillColor.r, fillColor.g, fillColor.b, fillColor.a);
 
   // Per-transition uniforms
   if (pd.directionLoc >= 0)

src/render/programs/wallpaper_program.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "config/config_service.h"
+#include "render/core/color.h"
 #include "render/core/mat3.h"
 #include "render/core/shader_program.h"
 
@@ -33,7 +34,7 @@ public:
   void draw(WallpaperTransition type, GLuint texture1, GLuint texture2, float surfaceWidth, float surfaceHeight,
             float quadWidth, float quadHeight, float imageWidth1, float imageHeight1, float imageWidth2,
             float imageHeight2, float progress, float fillMode, const TransitionParams& params,
-            const Mat3& transform = Mat3::identity()) const;
+            const Color& fillColor = rgba(0.0f, 0.0f, 0.0f, 1.0f), const Mat3& transform = Mat3::identity()) const;
 
 private:
   static constexpr std::size_t kTransitionCount = 6;

src/render/render_context.cpp

@@ -298,7 +298,7 @@ void RenderContext::renderNode(const Node* node, const Mat3& parentTransform, fl
       m_wallpaperProgram.draw(wallpaper->transition(), wallpaper->texture1(), texture2, sw, sh, node->width(),
                               node->height(), wallpaper->imageWidth1(), wallpaper->imageHeight1(), imageWidth2,
                               imageHeight2, progress, static_cast<float>(wallpaper->fillMode()),
-                              wallpaper->transitionParams(), worldTransform);
+                              wallpaper->transitionParams(), wallpaper->fillColor(), worldTransform);
     }
     break;
   }

src/render/scene/wallpaper_node.h

@@ -19,6 +19,7 @@ public:
   [[nodiscard]] float progress() const noexcept { return m_progress; }
   [[nodiscard]] WallpaperTransition transition() const noexcept { return m_transition; }
   [[nodiscard]] WallpaperFillMode fillMode() const noexcept { return m_fillMode; }
+  [[nodiscard]] const Color& fillColor() const noexcept { return m_fillColor; }
   [[nodiscard]] const TransitionParams& transitionParams() const noexcept { return m_params; }
 
   void setTextures(std::uint32_t texture1, std::uint32_t texture2, float imageWidth1, float imageHeight1,
@@ -58,6 +59,14 @@ public:
     markPaintDirty();
   }
 
+  void setFillColor(const Color& fillColor) {
+    if (m_fillColor == fillColor) {
+      return;
+    }
+    m_fillColor = fillColor;
+    markPaintDirty();
+  }
+
 private:
   std::uint32_t m_texture1 = 0;
   std::uint32_t m_texture2 = 0;
@@ -68,5 +77,6 @@ private:
   float m_progress = 0.0f;
   WallpaperTransition m_transition = WallpaperTransition::Fade;
   WallpaperFillMode m_fillMode = WallpaperFillMode::Crop;
+  Color m_fillColor = rgba(0.0f, 0.0f, 0.0f, 1.0f);
   TransitionParams m_params;
 };

src/render/wallpaper_renderer.cpp

@@ -99,7 +99,7 @@ void WallpaperRenderer::render() {
   float progress = (m_tex2 != 0) ? m_progress : 0.0f;
 
   m_program.draw(m_transition, m_tex1, tex2, sw, sh, sw, sh, m_imgW1, m_imgH1, m_imgW2, m_imgH2, progress,
-                 static_cast<float>(m_fillMode), m_params);
+                 static_cast<float>(m_fillMode), m_params, m_fillColor);
 
   eglSwapBuffers(m_eglDisplay, m_eglSurface);
 }
@@ -125,7 +125,7 @@ void WallpaperRenderer::renderToFbo(GLuint targetFbo) {
   float progress = (m_tex2 != 0) ? m_progress : 0.0f;
 
   m_program.draw(m_transition, m_tex1, tex2, sw, sh, sw, sh, m_imgW1, m_imgH1, m_imgW2, m_imgH2, progress,
-                 static_cast<float>(m_fillMode), m_params);
+                 static_cast<float>(m_fillMode), m_params, m_fillColor);
   // No eglSwapBuffers — caller is responsible for presentation
 }
 

src/render/wallpaper_renderer.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "config/config_service.h"
+#include "render/core/color.h"
 #include "render/programs/wallpaper_program.h"
 
 #include <EGL/egl.h>
@@ -56,5 +57,6 @@ private:
   float m_progress = 0.0f;
   WallpaperTransition m_transition = WallpaperTransition::Fade;
   WallpaperFillMode m_fillMode = WallpaperFillMode::Crop;
+  Color m_fillColor = rgba(0.0f, 0.0f, 0.0f, 1.0f);
   TransitionParams m_params;
 };

src/shell/lockscreen/lock_screen.cpp

@@ -6,6 +6,7 @@
 #include "ipc/ipc_service.h"
 #include "render/render_context.h"
 #include "shell/lockscreen/lock_surface.h"
+#include "ui/palette.h"
 #include "wayland/wayland_connection.h"
 #include "wayland/wayland_seat.h"
 
@@ -18,6 +19,13 @@ namespace {
 
   constexpr Logger kLog("lockscreen");
 
+  Color resolveWallpaperFillColor(const WallpaperConfig& config) {
+    if (!config.fillColor) {
+      return rgba(0.0f, 0.0f, 0.0f, 0.0f);
+    }
+    return resolveThemeColor(*config.fillColor);
+  }
+
   const ext_session_lock_v1_listener kSessionLockListener = {
       .locked = &LockScreen::handleLocked,
       .finished = &LockScreen::handleFinished,
@@ -160,6 +168,9 @@ void LockScreen::onThemeChanged() {
   }
   for (auto& instance : m_instances) {
     if (instance.surface != nullptr) {
+      if (m_configService != nullptr) {
+        instance.surface->setWallpaperFillColor(resolveWallpaperFillColor(m_configService->config().wallpaper));
+      }
       instance.surface->onThemeChanged();
     }
   }
@@ -177,6 +188,7 @@ void LockScreen::onWallpaperChanged() {
     const std::string connectorName = output != nullptr ? output->connectorName : std::string{};
     instance.surface->setWallpaperPath(m_configService->getWallpaperPath(connectorName));
     instance.surface->setWallpaperFillMode(m_configService->config().wallpaper.fillMode);
+    instance.surface->setWallpaperFillColor(resolveWallpaperFillColor(m_configService->config().wallpaper));
   }
 }
 
@@ -323,6 +335,7 @@ void LockScreen::createInstance(const WaylandOutput& output) {
   if (m_configService != nullptr) {
     surface->setWallpaperPath(m_configService->getWallpaperPath(output.connectorName));
     surface->setWallpaperFillMode(m_configService->config().wallpaper.fillMode);
+    surface->setWallpaperFillColor(resolveWallpaperFillColor(m_configService->config().wallpaper));
   }
   surface->setOnLogin([this]() { tryAuthenticate(); });
   surface->setOnPasswordChanged([this](const std::string& value) { handlePasswordEdited(value); });

src/shell/lockscreen/lock_surface.cpp

@@ -170,6 +170,24 @@ void LockSurface::setWallpaperFillMode(WallpaperFillMode fillMode) {
   requestRedraw();
 }
 
+void LockSurface::setWallpaperFillColor(Color fillColor) {
+  if (m_wallpaperFillColor == fillColor) {
+    return;
+  }
+  m_wallpaperFillColor = fillColor;
+  if (m_wallpaper != nullptr) {
+    m_wallpaper->setFillColor(m_wallpaperFillColor);
+  }
+  if (m_backdrop != nullptr) {
+    m_backdrop->setVisible(m_wallpaperFillColor.a > 0.0f);
+    m_backdrop->setStyle(RoundedRectStyle{
+        .fill = m_wallpaperFillColor,
+        .fillMode = FillMode::Solid,
+    });
+  }
+  requestRedraw();
+}
+
 void LockSurface::setOnLogin(std::function<void()> onLogin) { m_onLogin = std::move(onLogin); }
 
 void LockSurface::setOnPasswordChanged(std::function<void(const std::string&)> onPasswordChanged) {
@@ -288,10 +306,15 @@ void LockSurface::layoutScene(std::uint32_t width, std::uint32_t height) {
   m_wallpaper->setPosition(0.0f, 0.0f);
   m_wallpaper->setSize(sw, sh);
   m_wallpaper->setFillMode(m_wallpaperFillMode);
+  m_wallpaper->setFillColor(m_wallpaperFillColor);
 
   m_backdrop->setPosition(0.0f, 0.0f);
   m_backdrop->setSize(sw, sh);
-  m_backdrop->setVisible(false);
+  m_backdrop->setVisible(m_wallpaperFillColor.a > 0.0f);
+  m_backdrop->setStyle(RoundedRectStyle{
+      .fill = m_wallpaperFillColor,
+      .fillMode = FillMode::Solid,
+  });
 
   constexpr float kClockFontSize = 64.0f;
   m_clock->setFontSize(kClockFontSize);
@@ -353,6 +376,7 @@ void LockSurface::applyWallpaperTexture() {
                              static_cast<float>(m_wallpaperTexture.height), 0.0f, 0.0f);
     m_wallpaper->setTransition(WallpaperTransition::Fade, 0.0f, TransitionParams{});
     m_wallpaper->setFillMode(m_wallpaperFillMode);
+    m_wallpaper->setFillColor(m_wallpaperFillColor);
   } else {
     m_wallpaperTexture = {};
     m_wallpaper->setTextures(0, 0, 0.0f, 0.0f, 0.0f, 0.0f);

src/shell/lockscreen/lock_surface.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "config/config_service.h"
+#include "render/core/color.h"
 #include "render/core/texture_manager.h"
 #include "render/scene/input_dispatcher.h"
 #include "render/scene/node.h"
@@ -37,6 +38,7 @@ public:
   void setTextureCache(SharedTextureCache* cache) noexcept { m_textureCache = cache; }
   void setWallpaperPath(std::string wallpaperPath);
   void setWallpaperFillMode(WallpaperFillMode fillMode);
+  void setWallpaperFillColor(Color fillColor);
   void setOnLogin(std::function<void()> onLogin);
   void setOnPasswordChanged(std::function<void(const std::string&)> onPasswordChanged);
   void selectAllPassword();
@@ -71,6 +73,7 @@ private:
   TextureHandle m_wallpaperTexture{};
   std::string m_wallpaperPath;
   WallpaperFillMode m_wallpaperFillMode = WallpaperFillMode::Crop;
+  Color m_wallpaperFillColor = rgba(0.0f, 0.0f, 0.0f, 0.0f);
   bool m_wallpaperDirty = false;
   InputDispatcher m_inputDispatcher;
   std::function<void()> m_onLogin;

src/shell/wallpaper/wallpaper.cpp

@@ -4,7 +4,10 @@
 #include "core/log.h"
 #include "core/random.h"
 #include "render/core/shared_texture_cache.h"
+#include "render/programs/rect_program.h"
 #include "render/render_context.h"
+#include "render/scene/rect_node.h"
+#include "ui/palette.h"
 #include "wayland/wayland_connection.h"
 
 #include <algorithm>
@@ -164,6 +167,13 @@ namespace {
 
   constexpr Logger kLog("wallpaper");
 
+  Color resolveWallpaperFillColor(const WallpaperConfig& config) {
+    if (!config.fillColor) {
+      return rgba(0.0f, 0.0f, 0.0f, 0.0f);
+    }
+    return resolveThemeColor(*config.fillColor);
+  }
+
 } // namespace
 
 Wallpaper::Wallpaper() = default;
@@ -187,6 +197,14 @@ bool Wallpaper::initialize(WaylandConnection& wayland, ConfigService* config, Re
   }
 
   m_config->addReloadCallback([this]() { reload(); });
+  m_paletteConn = paletteChanged().connect([this] {
+    for (auto& inst : m_instances) {
+      updateRendererState(*inst);
+      if (inst->surface != nullptr) {
+        inst->surface->requestRedraw();
+      }
+    }
+  });
 
   resetAutomationState();
   syncInstances();
@@ -233,11 +251,26 @@ void Wallpaper::onStateChange() {
 
   for (auto& inst : m_instances) {
     auto newPath = m_config->getWallpaperPath(inst->connectorName);
-    if (newPath.empty()) {
+    if (inst->surface == nullptr || inst->wallpaperNode == nullptr) {
       continue;
     }
 
-    if (inst->surface == nullptr || inst->wallpaperNode == nullptr) {
+    if (newPath.empty()) {
+      if (!inst->currentPath.empty() || inst->currentTexture.id != 0 || inst->nextTexture.id != 0) {
+        if (inst->transitionAnimId != 0) {
+          inst->animations.cancel(inst->transitionAnimId);
+          inst->transitionAnimId = 0;
+        }
+        releaseInstanceTextures(*inst);
+        inst->currentTexture = {};
+        inst->nextTexture = {};
+        inst->currentPath.clear();
+        inst->pendingPath.clear();
+        inst->queuedPath.clear();
+        inst->transitioning = false;
+        updateRendererState(*inst);
+        inst->surface->requestRedraw();
+      }
       continue;
     }
 
@@ -401,6 +434,8 @@ void Wallpaper::createInstance(const WaylandOutput& output) {
 
   instance->sceneRoot = std::make_unique<Node>();
   instance->sceneRoot->setAnimationManager(&instance->animations);
+  auto fillNode = std::make_unique<RectNode>();
+  instance->fillNode = static_cast<RectNode*>(instance->sceneRoot->addChild(std::move(fillNode)));
   auto wallpaperNode = std::make_unique<WallpaperNode>();
   instance->wallpaperNode = static_cast<WallpaperNode*>(instance->sceneRoot->addChild(std::move(wallpaperNode)));
   instance->surface->setSceneRoot(instance->sceneRoot.get());
@@ -410,6 +445,8 @@ void Wallpaper::createInstance(const WaylandOutput& output) {
     const float sw = static_cast<float>(width);
     const float sh = static_cast<float>(height);
     inst->sceneRoot->setSize(sw, sh);
+    inst->fillNode->setPosition(0.0f, 0.0f);
+    inst->fillNode->setSize(sw, sh);
     inst->wallpaperNode->setPosition(0.0f, 0.0f);
     inst->wallpaperNode->setSize(sw, sh);
 
@@ -529,11 +566,19 @@ void Wallpaper::updateRendererState(WallpaperInstance& instance) {
   }
 
   const auto& wpConfig = m_config->config().wallpaper;
+  const Color fillColor = resolveWallpaperFillColor(wpConfig);
 
+  if (instance.fillNode != nullptr) {
+    instance.fillNode->setStyle(RoundedRectStyle{
+        .fill = fillColor,
+        .fillMode = FillMode::Solid,
+    });
+  }
   wallpaperNode->setTextures(
       instance.currentTexture.id, instance.nextTexture.id, static_cast<float>(instance.currentTexture.width),
       static_cast<float>(instance.currentTexture.height), static_cast<float>(instance.nextTexture.width),
       static_cast<float>(instance.nextTexture.height));
   wallpaperNode->setTransition(instance.activeTransition, instance.transitionProgress, instance.transitionParams);
   wallpaperNode->setFillMode(wpConfig.fillMode);
+  wallpaperNode->setFillColor(fillColor);
 }

src/shell/wallpaper/wallpaper.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "shell/wallpaper/wallpaper_instance.h"
+#include "ui/signal.h"
 
 #include <cstdint>
 #include <memory>
@@ -41,5 +42,6 @@ private:
   SharedTextureCache* m_textureCache = nullptr;
   std::int64_t m_lastAutomationMinuteStamp = -1;
   std::int64_t m_lastAutomationSwitchMinute = -1;
+  Signal<>::ScopedConnection m_paletteConn;
   std::vector<std::unique_ptr<WallpaperInstance>> m_instances;
 };

src/shell/wallpaper/wallpaper_instance.h

@@ -11,6 +11,8 @@
 #include <memory>
 #include <string>
 
+class RectNode;
+
 struct WallpaperInstance {
   std::uint32_t outputName = 0;
   struct wl_output* output = nullptr;
@@ -19,6 +21,7 @@ struct WallpaperInstance {
 
   std::unique_ptr<LayerSurface> surface;
   std::unique_ptr<Node> sceneRoot;
+  RectNode* fillNode = nullptr;
   WallpaperNode* wallpaperNode = nullptr;
   AnimationManager animations;