add weather intensity (WIP)

src/presets/WeatherPreset.hpp

@@ -18,10 +18,24 @@ struct WeatherPreset : Serializable {
         float hspeed = 0.1f;
         /// @brief UV scaling
         float scale = 0.1f;
+        /// @brief Fall opacity interpreted as zero.
+        /// @example if 0.8 then opacity range is 0.8-1.0 for 0.0-1.0 intensity
+        float minOpacity = 0.8f;
         /// @brief Fall splash
         std::optional<ParticlesPreset> splash;
     } fall {};
 
+    /// @brief Max weather fog opacity
+    float fogOpacity = 0.8f;
+
+    /// @brief Weather fog depth multiplier
+    float fogDencity = 2.0f;
+
+    float clouds = 0.5f;
+
+    /// @brief Weather effects intensity
+    float intensity = 0.9f;
+
     dv::value serialize() const override;
     void deserialize(const dv::value& src) override;
 };