Add ShadowsResolution for manually specified shadowmap resolution for lights

Source/Engine/Level/Actors/DirectionalLight.cpp

@@ -40,6 +40,7 @@ void DirectionalLight::Draw(RenderContext& renderContext)
         data.CastVolumetricShadow = CastVolumetricShadow;
         data.ShadowsUpdateRate = ShadowsUpdateRate;
         data.ShadowFrame = _invalidateShadowFrame;
+        data.ShadowsResolution = (int32)ShadowsResolution;
         data.ShadowsUpdateRateAtDistance = ShadowsUpdateRateAtDistance;
         data.ShadowsMode = ShadowsMode;
         data.CascadeCount = CascadeCount;

Source/Engine/Level/Actors/Light.h

@@ -66,7 +66,7 @@ public:
         const Vector3 size(50);
         return BoundingBox(_transform.Translation - size, _transform.Translation + size);
     }
-    
+
     virtual void DrawLightsDebug(RenderView& view);
 #endif
     void Serialize(SerializeStream& stream, const void* otherObj) override;
@@ -79,6 +79,26 @@ public:
 API_CLASS(Abstract) class FLAXENGINE_API LightWithShadow : public Light
 {
     DECLARE_SCENE_OBJECT_ABSTRACT(LightWithShadow);
+
+    /// <summary>
+    /// List of fixed resolutions for light shadow map.
+    /// </summary>
+    API_ENUM() enum class ShadowMapResolution
+    {
+        // Use automatic dynamic resolution based on distance to view.
+        Dynamic = 0,
+        // Shadow map of size 128x128.
+        _128 = 128,
+        // Shadow map of size 256x256.
+        _256 = 256,
+        // Shadow map of size 512x512.
+        _512 = 512,
+        // Shadow map of size 1024x1024.
+        _1024 = 1024,
+        // Shadow map of size 2048x2048.
+        _2048 = 2048,
+    };
+
 protected:
     uint32 _invalidateShadowFrame = 0;
 
@@ -143,12 +163,18 @@ public:
     API_FIELD(Attributes="EditorOrder(105), EditorDisplay(\"Shadow\", \"Update Rate At Distance\"), Limit(0.0f, 1.0f)")
     float ShadowsUpdateRateAtDistance = 0.5f;
 
+    /// <summary>
+    /// Defines the resolution of the shadow map texture used to draw objects projection from light-point-of-view. Higher values increase shadow quality at cost of performance.
+    /// </summary>
+    API_FIELD(Attributes="EditorOrder(105), EditorDisplay(\"Shadow\", \"Resolution\")")
+    ShadowMapResolution ShadowsResolution = ShadowMapResolution::Dynamic;
+
     /// <summary>
     /// Describes how a visual element casts shadows.
     /// </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>

Source/Engine/Level/Actors/PointLight.cpp

@@ -106,6 +106,7 @@ void PointLight::Draw(RenderContext& renderContext)
         data.ShadowsUpdateRate = ShadowsUpdateRate;
         data.ShadowsUpdateRateAtDistance = ShadowsUpdateRateAtDistance;
         data.ShadowFrame = _invalidateShadowFrame;
+        data.ShadowsResolution = (int32)ShadowsResolution;
         data.ShadowsMode = ShadowsMode;
         data.Radius = radius;
         data.FallOffExponent = FallOffExponent;

Source/Engine/Level/Actors/SpotLight.cpp

@@ -156,6 +156,7 @@ void SpotLight::Draw(RenderContext& renderContext)
         data.ShadowsUpdateRate = ShadowsUpdateRate;
         data.ShadowsUpdateRateAtDistance = ShadowsUpdateRateAtDistance;
         data.ShadowFrame = _invalidateShadowFrame;
+        data.ShadowsResolution = (int32)ShadowsResolution;
         data.ShadowsMode = ShadowsMode;
         data.Radius = radius;
         data.FallOffExponent = FallOffExponent;

Source/Engine/Renderer/RenderList.h

@@ -59,6 +59,7 @@ struct RenderLightData
     float ShadowsUpdateRate;
     float ShadowsUpdateRateAtDistance;
     uint32 ShadowFrame;
+    int32 ShadowsResolution;
 
     bool CanRenderShadow(const RenderView& view) const;
 };

Source/Engine/Renderer/ShadowsPass.cpp

@@ -142,6 +142,7 @@ struct ShadowAtlasLightCache
     float Distance;
     Float4 CascadeSplits;
     Float3 ViewDirection;
+    int32 ShadowsResolution;
 
     void Set(const RenderView& view, const RenderLightData& light, const Float4& cascadeSplits = Float4::Zero)
     {
@@ -152,6 +153,7 @@ struct ShadowAtlasLightCache
         ShadowsUpdateRateAtDistance = light.ShadowsUpdateRateAtDistance;
         Direction = light.Direction;
         ShadowFrame = light.ShadowFrame;
+        ShadowsResolution = light.ShadowsResolution;
         if (light.IsDirectionalLight)
         {
             // Sun
@@ -247,6 +249,7 @@ struct ShadowAtlasLight
             !Math::NearEqual(Cache.ShadowsUpdateRate, light.ShadowsUpdateRate) ||
             !Math::NearEqual(Cache.ShadowsUpdateRateAtDistance, light.ShadowsUpdateRateAtDistance) ||
             Cache.ShadowFrame != light.ShadowFrame ||
+            Cache.ShadowsResolution != light.ShadowsResolution ||
             Float3::Dot(Cache.Direction, light.Direction) < SHADOWS_ROTATION_ERROR)
         {
             // Invalidate
@@ -1119,9 +1122,12 @@ void ShadowsPass::SetupShadows(RenderContext& renderContext, RenderContextBatch&
         auto& atlasLight = shadows.Lights[light->ID];
 
         // Calculate resolution for this light
-        // TODO: add support for fixed shadow map resolution assigned per-light
-        float lightResolutionFloat = baseLightResolution * light->ScreenSize;
-        atlasLight.Resolution = QuantizeResolution(lightResolutionFloat);
+        atlasLight.Resolution = light->ShadowsResolution;
+        if (atlasLight.Resolution == 0)
+        {
+            // ScreenSize-based automatic shadowmap resolution
+            atlasLight.Resolution = QuantizeResolution(baseLightResolution * light->ScreenSize);
+        }
 
         // Cull too small lights
         if (atlasLight.Resolution < SHADOWS_MIN_RESOLUTION)