refactor blocks layers

src/world/generator/GeneratorDef.hpp

@@ -18,6 +18,11 @@ struct BlocksLayer {
     } rt;
 };
 
+struct BlocksLayers {
+    std::vector<BlocksLayer> layers;
+    uint lastLayersHeight;
+};
+
 class GeneratorScript {
 public:
     virtual ~GeneratorScript() = default;
@@ -25,12 +30,8 @@ public:
     virtual std::shared_ptr<Heightmap> generateHeightmap(
         const glm::ivec2& offset, const glm::ivec2& size, uint64_t seed) = 0;
 
-    virtual const std::vector<BlocksLayer>& getLayers() const = 0;
-    virtual const std::vector<BlocksLayer>& getSeaLayers() const = 0;
-
-    /// @brief Total height of all layers after resizeable one
-    virtual uint getLastLayersHeight() const = 0;
-    virtual uint getLastSeaLayersHeight() const = 0;
+    virtual const BlocksLayers& getGroundLayers() const = 0;
+    virtual const BlocksLayers& getSeaLayers() const = 0;
 
     virtual uint getSeaLevel() const = 0;