Fix sun quad visibility, minimap opacity, audio scaling, and rename music toggle

- Tighten celestial glow falloff and edge fade to eliminate visible quad boundary
- Add opacity support to minimap display shader, synced with UI opacity setting
- Fix audio double/triple-scaling by removing redundant master volume multiplications
- Rename "Original Soundtrack" toggle to "Enable WoWee Music"
- Add About tab with developer info and GitHub link

assets/shaders/celestial.frag.glsl

@@ -31,14 +31,13 @@ void main() {
     float disc = smoothstep(0.42, 0.35, dist);
 
     // Soft glow that fades to zero well within quad bounds
-    // At dist=0.5 (quad edge), this should be negligible
-    float glow = exp(-dist * dist * 18.0) * 0.5;
+    float glow = exp(-dist * dist * 32.0) * 0.5;
 
     // Combine disc and glow
     float alpha = max(disc, glow) * push.intensity;
 
     // Fade to zero well before quad edges
-    float edgeFade = 1.0 - smoothstep(0.35, 0.48, dist);
+    float edgeFade = 1.0 - smoothstep(0.30, 0.38, dist);
     alpha *= edgeFade;
 
     vec3 color = push.celestialColor.rgb;
@@ -56,7 +55,7 @@ void main() {
     float phaseShadow = smoothstep(-0.1, 0.1, phaseX);
     alpha *= mix(phaseShadow, 1.0, step(0.5, push.intensity));
 
-    if (alpha < 0.003) discard;
+    if (alpha < 0.01) discard;
     // Pre-multiply for additive blending: RGB is the light contribution
     outColor = vec4(color * alpha, alpha);
 }

assets/shaders/minimap_display.frag.glsl

@@ -9,6 +9,7 @@ layout(push_constant) uniform Push {
     float arrowRotation;
     float zoomRadius;
     int squareShape;
+    float opacity;
 } push;
 
 layout(location = 0) in vec2 TexCoord;
@@ -63,5 +64,5 @@ void main() {
         mapColor.rgb *= 1.0 - border * 0.7;
     }
 
-    outColor = mapColor;
+    outColor = vec4(mapColor.rgb, mapColor.a * push.opacity);
 }

include/rendering/minimap.hpp

@@ -53,6 +53,8 @@ public:
     void zoomIn() { viewRadius = std::max(100.0f, viewRadius - 50.0f); }
     void zoomOut() { viewRadius = std::min(800.0f, viewRadius + 50.0f); }
 
+    void setOpacity(float opacity) { opacity_ = opacity; }
+
     // Public accessors for WorldMap
     VkTexture* getOrLoadTileTexture(int tileX, int tileY);
     void ensureTRSParsed() { if (!trsParsed) parseTRS(); }
@@ -103,6 +105,7 @@ private:
     bool enabled = true;
     bool rotateWithCamera = false;
     bool squareShape = false;
+    float opacity_ = 1.0f;
 
     // Throttling
     float updateIntervalSec = 0.25f;

src/rendering/minimap.cpp

@@ -30,7 +30,8 @@ struct MinimapDisplayPush {
     float arrowRotation;
     float zoomRadius;
     int32_t squareShape;
-};  // 40 bytes
+    float opacity;
+};  // 44 bytes
 
 Minimap::Minimap() = default;
 
@@ -529,6 +530,7 @@ void Minimap::render(VkCommandBuffer cmd, const Camera& playerCamera,
     push.arrowRotation = arrowRotation;
     push.zoomRadius = zoomRadius;
     push.squareShape = squareShape ? 1 : 0;
+    push.opacity = opacity_;
 
     vkCmdPushConstants(cmd, displayPipelineLayout,
                        VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT,

src/ui/game_screen.cpp

@@ -196,6 +196,16 @@ void GameScreen::render(game::GameHandler& gameHandler) {
     float prevAlpha = ImGui::GetStyle().Alpha;
     ImGui::GetStyle().Alpha = uiOpacity_;
 
+    // Sync minimap opacity with UI opacity
+    {
+        auto* renderer = core::Application::getInstance().getRenderer();
+        if (renderer) {
+            if (auto* minimap = renderer->getMinimap()) {
+                minimap->setOpacity(uiOpacity_);
+            }
+        }
+    }
+
     // Apply initial settings when renderer becomes available
     if (!minimapSettingsApplied_) {
         auto* renderer = core::Application::getInstance().getRenderer();
@@ -6144,7 +6154,7 @@ void GameScreen::renderSettingsWindow() {
                 }
                 ImGui::Separator();
 
-                if (ImGui::Checkbox("Original Soundtrack", &pendingUseOriginalSoundtrack)) {
+                if (ImGui::Checkbox("Enable WoWee Music", &pendingUseOriginalSoundtrack)) {
                     if (renderer) {
                         if (auto* zm = renderer->getZoneManager()) {
                             zm->setUseOriginalSoundtrack(pendingUseOriginalSoundtrack);
@@ -6153,7 +6163,7 @@ void GameScreen::renderSettingsWindow() {
                     saveSettings();
                 }
                 if (ImGui::IsItemHovered())
-                    ImGui::SetTooltip("Include original music tracks in zone music rotation");
+                    ImGui::SetTooltip("Include WoWee music tracks in zone music rotation");
                 ImGui::Separator();
 
                 ImGui::Text("Music");