Add outline to stream overlay text (#1887)

Co-authored-by: Cameron Gutman <aicommander@gmail.com>

app/streaming/video/overlaymanager.cpp

@@ -149,10 +149,12 @@ void OverlayManager::notifyOverlayUpdated(OverlayType type)
         (void**)&m_Overlays[type].surface,
         m_Overlays[type].enabled ?
             // The _Wrapped variant is required for line breaks to work
-            TTF_RenderText_Blended_Wrapped(m_Overlays[type].font,
+            RenderTextOutlinedWrapped(m_Overlays[type].font,
-                                           m_Overlays[type].text,
+                                      m_Overlays[type].text,
-                                           m_Overlays[type].color,
+                                      m_Overlays[type].color,
-                                           1024)
+                                      {0, 0, 0, 255},
+                                      4,
+                                      1024)
             : nullptr);
 
     // Notify the renderer
@@ -163,3 +165,32 @@ void OverlayManager::notifyOverlayUpdated(OverlayType type)
         SDL_FreeSurface(oldSurface);
     }
 }
+
+SDL_Surface* OverlayManager::RenderTextOutlinedWrapped(TTF_Font* font, const char* text, SDL_Color textColor, SDL_Color outlineColor, int outlineWidth, int wrapWidth) {
+    if (text == nullptr || text[0] == '\0') {
+        return nullptr;
+    }
+
+    // Draw text twice, but outline is a bit bigger
+    int oldOutline = TTF_GetFontOutline(font);
+    TTF_SetFontOutline(font, outlineWidth);
+    auto outlineSurface = TTF_RenderText_Blended_Wrapped(font, text, outlineColor, wrapWidth);
+    TTF_SetFontOutline(font, 0);
+    auto textSurface = TTF_RenderText_Blended_Wrapped(font, text, textColor, wrapWidth);
+    TTF_SetFontOutline(font, oldOutline);
+
+    if (outlineSurface == nullptr || textSurface == nullptr) {
+        SDL_FreeSurface(outlineSurface);
+        SDL_FreeSurface(textSurface);
+        return nullptr;
+    }
+
+    // Merge the texts
+    SDL_Rect dst = { outlineWidth, outlineWidth, textSurface->w, textSurface->h };
+    SDL_BlitSurface(textSurface, nullptr, outlineSurface, &dst);
+
+    SDL_FreeSurface(textSurface);
+    return outlineSurface;
+}
+
+

app/streaming/video/overlaymanager.h

@@ -41,6 +41,7 @@ public:
 
 private:
     void notifyOverlayUpdated(OverlayType type);
+    SDL_Surface* RenderTextOutlinedWrapped(TTF_Font* font, const char* text, SDL_Color textColor, SDL_Color outlineColor, int outlineWidth, int wrapWidth);
 
     struct {
         bool enabled;