Add InvalidateShadow for manual shadow cache refresh

Source/Engine/Level/Actors/DirectionalLight.cpp

@@ -39,6 +39,7 @@ void DirectionalLight::Draw(RenderContext& renderContext)
         data.IndirectLightingIntensity = IndirectLightingIntensity;
         data.CastVolumetricShadow = CastVolumetricShadow;
         data.ShadowsUpdateRate = ShadowsUpdateRate;
+        data.ShadowFrame = _invalidateShadowFrame;
         data.ShadowsUpdateRateAtDistance = ShadowsUpdateRateAtDistance;
         data.ShadowsMode = ShadowsMode;
         data.CascadeCount = CascadeCount;

Source/Engine/Level/Actors/Light.cpp

@@ -84,6 +84,11 @@ LightWithShadow::LightWithShadow(const SpawnParams& params)
 {
 }
 
+void LightWithShadow::InvalidateShadow()
+{
+    _invalidateShadowFrame++;
+}
+
 void LightWithShadow::Serialize(SerializeStream& stream, const void* otherObj)
 {
     // Base

Source/Engine/Level/Actors/Light.h

@@ -79,6 +79,9 @@ public:
 API_CLASS(Abstract) class FLAXENGINE_API LightWithShadow : public Light
 {
     DECLARE_SCENE_OBJECT_ABSTRACT(LightWithShadow);
+protected:
+    uint32 _invalidateShadowFrame = 0;
+
 public:
     /// <summary>
     /// The minimum roughness value used to clamp material surface roughness during shading pixel.
@@ -145,6 +148,11 @@ public:
     /// </summary>
     API_FIELD(Attributes="EditorOrder(60), EditorDisplay(\"Shadow\", \"Mode\")")
     ShadowsCastingMode ShadowsMode = ShadowsCastingMode::All;
+    
+    /// <summary>
+    /// Marks the light shadow to be refreshes during next drawing. Invalidates any cached shadow map and redraws static shadows of the object (if any in use).
+    /// </summary>
+    API_FUNCTION() void InvalidateShadow();
 
 public:
     // [Light]

Source/Engine/Level/Actors/PointLight.cpp

@@ -105,6 +105,7 @@ void PointLight::Draw(RenderContext& renderContext)
         data.CastVolumetricShadow = CastVolumetricShadow;
         data.ShadowsUpdateRate = ShadowsUpdateRate;
         data.ShadowsUpdateRateAtDistance = ShadowsUpdateRateAtDistance;
+        data.ShadowFrame = _invalidateShadowFrame;
         data.ShadowsMode = ShadowsMode;
         data.Radius = radius;
         data.FallOffExponent = FallOffExponent;

Source/Engine/Level/Actors/SpotLight.cpp

@@ -155,6 +155,7 @@ void SpotLight::Draw(RenderContext& renderContext)
         data.CastVolumetricShadow = CastVolumetricShadow;
         data.ShadowsUpdateRate = ShadowsUpdateRate;
         data.ShadowsUpdateRateAtDistance = ShadowsUpdateRateAtDistance;
+        data.ShadowFrame = _invalidateShadowFrame;
         data.ShadowsMode = ShadowsMode;
         data.Radius = radius;
         data.FallOffExponent = FallOffExponent;