supporting directional lights

EffectInterfaces/DirectionalLightEffect.cs

@@ -0,0 +1,8 @@
+namespace Kav
+{
+    public interface DirectionalLightEffect
+    {
+        int MaxDirectionalLights { get; }
+        DirectionalLightCollection DirectionalLights { get; }
+    }
+}

Effects/HLSL/PBREffect.fx

@@ -23,12 +23,15 @@ BEGIN_CONSTANTS
 
     // Light Info
     float3 LightPositions[4]                    _ps(c4)     _cb(c4);
-    float3 LightColors[4]                       _ps(c8)     _cb(c8);
+    float3 PositionLightColors[4]               _ps(c8)     _cb(c8);
 
-    float3 EyePosition                          _ps(c12)    _cb(c12);
+    float3 LightDirections[4]                   _ps(c12)    _cb(c12); 
+    float3 DirectionLightColors[4]              _ps(c16)    _cb(c16);
 
-    float4x4 World                  _vs(c0)                 _cb(c16);
+    float3 EyePosition                          _ps(c20)    _cb(c20);
-    float4x4 WorldInverseTranspose  _vs(c4)                 _cb(c20);
+
+    float4x4 World                  _vs(c0)                 _cb(c21);
+    float4x4 WorldInverseTranspose  _vs(c4)                 _cb(c25);
 
 MATRIX_CONSTANTS
 
@@ -121,6 +124,36 @@ float3 GetNormalFromMap(float3 worldPos, float2 texCoords, float3 normal)
     return normalize(mul(tangentNormal, TBN));
 }
 
+float3 ComputeLight(
+    float3 lightDir,
+    float3 radiance,
+    float3 F0,
+    float3 V,
+    float3 N,
+    float3 albedo,
+    float metallic,
+    float roughness
+) {
+    float3 L = normalize(lightDir);
+    float3 H = normalize(V + L);
+
+    float NDF = DistributionGGX(N, H, roughness);
+    float G = GeometrySmith(N, V, L, roughness);
+    float3 F = FresnelSchlick(max(dot(H, V), 0.0), F0);
+
+    float3 numerator = NDF * G * F;
+    float denominator = 4.0 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0);
+    float3 specular = numerator / max(denominator, 0.001);
+
+    float3 kS = F;
+    float3 kD = float3(1.0, 1.0, 1.0) - kS;
+
+    kD *= 1.0 - metallic;
+
+    float NdotL = max(dot(N, L), 0.0);
+    return (kD * albedo / PI + specular) * radiance * NdotL;
+}
+
 float4 ComputeColor(
     float3 worldPosition, 
     float3 worldNormal, 
@@ -136,31 +169,24 @@ float4 ComputeColor(
 
     float3 Lo = float3(0.0, 0.0, 0.0);
 
+    // point light
     for (int i = 0; i < 4; i++)
     {
         float3 lightDir = LightPositions[i] - worldPosition;
-        float3 L = normalize(lightDir);
-        float3 H = normalize(V + L);
-
         float distance = length(lightDir);
         float attenuation = 1.0 / (distance * distance);
-        float3 radiance = LightColors[i] * attenuation;
+        float3 radiance = PositionLightColors[i] * attenuation;
 
-        float NDF = DistributionGGX(N, H, roughness);
+        Lo += ComputeLight(lightDir, radiance, F0, V, N, albedo, metallic, roughness);
-        float G = GeometrySmith(N, V, L, roughness);
+    }
-        float3 F = FresnelSchlick(max(dot(H, V), 0.0), F0);
 
-        float3 numerator = NDF * G * F;
+    // directional light
-        float denominator = 4.0 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0);
+    for (int i = 0; i < 4; i++)
-        float3 specular = numerator / max(denominator, 0.001);
+    {
+        float3 lightDir = LightDirections[i];
+        float3 radiance = DirectionLightColors[i];
 
-        float3 kS = F;
+        Lo += ComputeLight(lightDir, radiance, F0, V, N, albedo, metallic, roughness);
-        float3 kD = float3(1.0, 1.0, 1.0) - kS;
-
-        kD *= 1.0 - metallic;
-
-        float NdotL = max(dot(N, L), 0.0);
-        Lo += (kD * albedo / PI + specular) * radiance * NdotL;
     }
 
     float3 ambient = float3(0.03, 0.03, 0.03) * albedo * AO;

Effects/PBREffect.cs

@@ -45,7 +45,49 @@ namespace Kav
         }
     }
 
-    public class PBREffect : Effect, TransformEffect, PointLightEffect
+    public class DirectionalLightCollection
+    {
+        private readonly Vector3[] directions = new Vector3[4];
+        private readonly Vector3[] colors = new Vector3[4];
+        private readonly float[] intensities = new float[4];
+
+        readonly EffectParameter lightPositionsParam;
+        readonly EffectParameter lightColorsParam;
+
+        public DirectionalLightCollection(EffectParameter lightPositionsParam, EffectParameter lightColorsParam)
+        {
+            this.lightPositionsParam = lightPositionsParam;
+            this.lightColorsParam = lightColorsParam;
+        }
+
+        public DirectionalLight this[int i]
+        {
+            get
+            {
+                var color = colors[i] / intensities[i];
+                return new DirectionalLight(
+                    directions[i],
+                    new Color(
+                        color.X,
+                        color.Y,
+                        color.Z,
+                        1f
+                    ),
+                    intensities[i]
+                );
+            }
+            set
+            {
+                directions[i] = value.Direction;
+                colors[i] = value.Color.ToVector3() * value.Intensity;
+                intensities[i] = value.Intensity;
+                lightPositionsParam.SetValue(directions);
+                lightColorsParam.SetValue(colors);
+            }
+        }
+    }
+
+    public class PBREffect : Effect, TransformEffect, PointLightEffect, DirectionalLightEffect
     {
         EffectParameter worldParam;
         EffectParameter worldViewProjectionParam;
@@ -73,6 +115,7 @@ namespace Kav
         Matrix view = Matrix.Identity;
         Matrix projection = Matrix.Identity;
         PointLightCollection pointLightCollection;
+        DirectionalLightCollection directionalLightCollection;
 
         Vector3 albedo;
         float metallic;
@@ -122,7 +165,15 @@ namespace Kav
         public PointLightCollection PointLights
         {
             get { return pointLightCollection; }
-            internal set { pointLightCollection = value; }
+            private set { pointLightCollection = value; }
+        }
+
+        public int MaxDirectionalLights { get; } = 4;
+
+        public DirectionalLightCollection DirectionalLights
+        {
+            get { return directionalLightCollection; }
+            private set { directionalLightCollection = value; }
         }
 
         public Vector3 Albedo
@@ -234,7 +285,12 @@ namespace Kav
 
             pointLightCollection = new PointLightCollection(
                 Parameters["LightPositions"],
-                Parameters["LightColors"]
+                Parameters["PositionLightColors"]
+            );
+
+            directionalLightCollection = new DirectionalLightCollection(
+                Parameters["LightDirections"],
+                Parameters["DirectionLightColors"]
             );
         }
 
@@ -248,14 +304,24 @@ namespace Kav
 
             PointLights = new PointLightCollection(
                 Parameters["LightPositions"],
-                Parameters["LightColors"]
+                Parameters["PositionLightColors"]
             );
 
-            for (int i = 0; i < 4; i++)
+            for (int i = 0; i < MaxPointLights; i++)
             {
                 PointLights[i] = cloneSource.PointLights[i];
             }
 
+            DirectionalLights = new DirectionalLightCollection(
+                Parameters["LightDirections"],
+                Parameters["DirectionLightColors"]
+            );
+
+            for (int i = 0; i < MaxDirectionalLights; i++)
+            {
+                DirectionalLights[i] = cloneSource.DirectionalLights[i];
+            }
+
             AlbedoTexture = cloneSource.AlbedoTexture;
             NormalTexture = cloneSource.NormalTexture;
             EmissionTexture = cloneSource.EmissionTexture;

Geometry/Model.cs

@@ -10,19 +10,5 @@ namespace Kav
         {
             Meshes = meshes;
         }
-
-        public void ApplyTransform(Matrix transform)
-        {
-            foreach (var mesh in Meshes)
-            {
-                foreach (var meshPart in mesh.MeshParts)
-                {
-                    if (meshPart.Effect is TransformEffect transformEffect)
-                    {
-                        transformEffect.World = transform;
-                    }
-                }
-            }
-        }
     }
 }

Kav.csproj

@@ -18,6 +18,9 @@
     <EmbeddedResource Include="Effects\FXB\PBREffect.fxb">
       <LogicalName>Kav.Resources.PBREffect.fxb</LogicalName>
 		</EmbeddedResource>
+    <EmbeddedResource Include="Effects\FXB\SimpleDepthEffect.fxb">
+      <LogicalName>Kav.Resources.SimpleDepthEffect.fxb</LogicalName>
+		</EmbeddedResource>
   </ItemGroup>
 
 </Project>

Lights/DirectionalLight.cs

@@ -0,0 +1,34 @@
+using Microsoft.Xna.Framework;
+
+namespace Kav
+{
+    public struct DirectionalLight
+    {
+        public Vector3 Direction { get; set; }
+        public Color Color { get; set; }
+        public float Intensity { get; set; }
+
+        public Matrix View
+        {
+            get
+            {
+                return Matrix.CreateLookAt(-Direction * 100f, Vector3.Zero, Vector3.Up);
+            }
+        }
+
+        public Matrix Projection
+        {
+            get
+            {
+                return Matrix.CreateOrthographic(20f, 20f, 1f, 101f);
+            }
+        }
+
+        public DirectionalLight(Vector3 direction, Color color, float intensity = 1f)
+        {
+            Direction = direction;
+            Color = color;
+            Intensity = intensity;
+        }
+    }
+}

Lights/PointLight.cs

@@ -2,11 +2,11 @@ using Microsoft.Xna.Framework;
 
 namespace Kav
 {
-    public class PointLight
+    public struct PointLight
     {
-        public Vector3 Position { get; set; }
+        public Vector3 Position { get; }
-        public Color Color { get; set; }
+        public Color Color { get; }
-        public float Intensity { get; set; }
+        public float Intensity { get; }
 
         public PointLight(Vector3 position, Color color, float intensity = 1f)
         {

Renderer.cs

@@ -31,19 +31,23 @@ namespace Kav
             SimpleDepthEffect = new SimpleDepthEffect(GraphicsDevice);
         }
 
-        public void Render(Camera camera, IEnumerable<Model> models, IEnumerable<PointLight> pointLights)
+        public void Render(
-        {
+            Camera camera, 
-            Render(camera.View, camera.Projection, models, pointLights);
+            IEnumerable<(Model, Matrix)> modelTransforms, 
+            IEnumerable<PointLight> pointLights,
+            IEnumerable<DirectionalLight> directionalLights
+        ) {
+            Render(camera.View, camera.Projection, modelTransforms, pointLights, directionalLights);
         }
 
         // for shadow mapping
-        public void DepthRender(Matrix view, Matrix projection, IEnumerable<(Model, Matrix)> modelTransforms, IEnumerable<PointLight> pointLights)
+        public void DepthRender(IEnumerable<(Model, Matrix)> modelTransforms, DirectionalLight directionalLight)
         {
             GraphicsDevice.SetRenderTarget(DepthRenderTarget);
             GraphicsDevice.Clear(ClearOptions.DepthBuffer, Color.Black, 1, 0);
 
-            SimpleDepthEffect.View = view;
+            SimpleDepthEffect.View = directionalLight.View;
-            SimpleDepthEffect.Projection = projection;
+            SimpleDepthEffect.Projection = directionalLight.Projection;
 
             foreach (var (model, transform) in modelTransforms)
             {
@@ -74,9 +78,14 @@ namespace Kav
             }
         }
 
-        private void Render(Matrix view, Matrix projection, IEnumerable<Model> models, IEnumerable<PointLight> pointLights)
+        private void Render(
-        {
+            Matrix view,
-            foreach (var model in models)
+            Matrix projection,
+            IEnumerable<(Model, Matrix)> modelTransforms,
+            IEnumerable<PointLight> pointLights,
+            IEnumerable<DirectionalLight> directionalLights
+        ) {
+            foreach (var (model, transform) in modelTransforms)
             {
                 foreach (var modelMesh in model.Meshes)
                 {
@@ -87,6 +96,7 @@ namespace Kav
 
                         if (meshPart.Effect is TransformEffect transformEffect)
                         {
+                            transformEffect.World = transform;
                             transformEffect.View = view;
                             transformEffect.Projection = projection;
                         }
@@ -102,6 +112,17 @@ namespace Kav
                             }
                         }
 
+                        if (meshPart.Effect is DirectionalLightEffect directionalLightEffect)
+                        {
+                            int i = 0;
+                            foreach (var directionalLight in directionalLights)
+                            {
+                                if (i > directionalLightEffect.MaxDirectionalLights) { break; }
+                                directionalLightEffect.DirectionalLights[i] = directionalLight;
+                                i++;
+                            }
+                        }
+
                         foreach (var pass in meshPart.Effect.CurrentTechnique.Passes)
                         {
                             pass.Apply();

Resources.cs

@@ -22,7 +22,7 @@ namespace Kav
             {
                 if (simpleDepthEffect == null)
                 {
-                    simpleDepthEffect = GetResource("SimpleDepthEffecT");
+                    simpleDepthEffect = GetResource("SimpleDepthEffect");
                 }
                 return simpleDepthEffect;
             }