Better design that has a render/update cycle for components.

src/guecs/ui.cpp

@@ -80,11 +80,7 @@ namespace guecs {
     });
 
     query<lel::Cell, Meter>([this](auto ent, auto &cell, auto& meter) {
-      if(auto bg = get_if<Rectangle>(ent)) {
-        meter.init(cell, *bg);
-      } else {
-        meter.init(cell);
-      }
+      meter.init(cell);
     });
 
     query<lel::Cell, Text>([this](auto, auto& cell, auto& text) {
@@ -119,6 +115,16 @@ namespace guecs {
     }
   }
 
+  void UI::update() {
+    query<Rectangle>([&](auto ent, auto& rect) {
+      rect.update();
+    });
+
+    query<Meter>([&](auto ent, auto &meter) {
+      meter.update();
+    });
+  }
+
   // BUG: either render detects that the things are initialized or there's
   // another validator function I can call in debug modes to confirm they are
   void UI::render(sf::RenderTarget& window) {