Add Graphics.ShadowUpdateRate to control global shadows atlas update rate

Source/Engine/Graphics/Graphics.cpp

@@ -18,6 +18,7 @@ Quality Graphics::SSAOQuality = Quality::Medium;
 Quality Graphics::VolumetricFogQuality = Quality::High;
 Quality Graphics::ShadowsQuality = Quality::Medium;
 Quality Graphics::ShadowMapsQuality = Quality::Medium;
+float Graphics::ShadowUpdateRate = 1.0f;
 bool Graphics::AllowCSMBlending = false;
 Quality Graphics::GlobalSDFQuality = Quality::High;
 Quality Graphics::GIQuality = Quality::High;

Source/Engine/Graphics/Graphics.h

@@ -48,6 +48,11 @@ public:
     /// </summary>
     API_FIELD() static Quality ShadowMapsQuality;
 
+    /// <summary>
+    /// The global scale for all shadow maps update rate. Can be used to slow down shadows rendering frequency on lower quality settings or low-end platforms. Default 1.
+    /// </summary>
+    API_FIELD() static float ShadowUpdateRate;
+
     /// <summary>
     /// Enables cascades splits blending for directional light shadows.
     /// [Deprecated in v1.9]

Source/Engine/Renderer/ShadowsPass.cpp

@@ -224,7 +224,7 @@ struct ShadowAtlasLight
         const float shadowsUpdateRate = light.ShadowsUpdateRate;
         const float shadowsUpdateRateAtDistance = shadowsUpdateRate * light.ShadowsUpdateRateAtDistance;
         float updateRate = Math::Lerp(shadowsUpdateRate, shadowsUpdateRateAtDistance, Math::Saturate(distanceFromView / Distance));
-        // TODO: add global shadows update rate scale to be adjusted per-platform
+        updateRate *= Graphics::ShadowUpdateRate;
         freezeUpdate = updateRate <= ZeroTolerance;
         if (freezeUpdate)
             return 0.0f;