Preserve 16:9 tile aspect on resize

TileLayout.hpp

@@ -9,18 +9,38 @@ struct Vertex
     float uv[2];
 };
 
+struct TileRect
+{
+    float x0;
+    float y0;
+    float x1;
+    float y1;
+};
+
+std::vector<TileRect> makeGridTileRects(
+    uint32_t cols,
+    uint32_t rows,
+    float viewportWidth,
+    float viewportHeight,
+    float gapPixels,
+    float targetAspect);
+
 std::vector<Vertex> makeGridLayout(
     uint32_t cols,
     uint32_t rows,
-    float gapX,
-    float gapY);
+    float viewportWidth,
+    float viewportHeight,
+    float gapPixels,
+    float targetAspect);
 
 void updateGridLayout(
     Vertex* vertices,
     uint32_t cols,
     uint32_t rows,
-    float gapX,
-    float gapY);
+    float viewportWidth,
+    float viewportHeight,
+    float gapPixels,
+    float targetAspect);
 
 void updateUvForAspectRatio(
     Vertex* vertices,