Added an exponential falloff to the PCF filtering radius as an attempt to make the shadows better transition from hard to soft. Still not entirely sold on it, but I think it's better.

If you want to remove it, it's the line after 'penumbra' is declared in the PCSS_Main function of the PCSS shader

Author: TheMasonX

Assets/PCSS/Demo/Demo Assets/Materials/GroundPlane.mat

@@ -236,7 +236,8 @@ private void GetInput(out float speed)
 
         private void RotateView()
         {
-            m_MouseLook.LookRotation (transform, m_Camera.transform);
+            if(!UnityEngine.VR.VRSettings.enabled)
+                m_MouseLook.LookRotation (transform, m_Camera.transform);
         }
 
 

Assets/PCSS/Demo/Demo Assets/Palm Trees/Materials/Palm.mat

@@ -23,6 +23,10 @@ public class PCSSLight : MonoBehaviour
     [Space(20f)]
     [Range(0f, 7.5f)]
     public float Softness = 1f;
+    [Range(0f, 5f)]
+    public float SoftnessFalloff = 4f;
+    //[Range(0f, 1f)]
+    //public float NearPlane = .1f;
 
     [Space(20f)]
     [Range(0f, 0.15f)]
@@ -53,7 +57,7 @@ public class PCSSLight : MonoBehaviour
     private CommandBuffer copyShadowBuffer;
     private Light _light;
 
-
+    #region Initialization
     public void OnEnable ()
     {
         Setup();
@@ -101,6 +105,13 @@ public void Setup ()
         UpdateCommandBuffer();
     }
 
+    public void CreateShadowRenderTexture ()
+    {
+        shadowRenderTexture = new RenderTexture(resolution, resolution, 0, format);
+        shadowRenderTexture.filterMode = filterMode;
+        shadowRenderTexture.useMipMap = false;
+    }
+
     [ContextMenu("Reset Shadows To Default")]
     public void ResetShadowMode ()
     {
@@ -115,7 +126,9 @@ public void ResetShadowMode ()
 
         _light.RemoveCommandBuffer(LightEvent.AfterShadowMap, copyShadowBuffer);
     }
+    #endregion
 
+    #region UpdateSettings
     public void UpdateShaderValues ()
     {
         Shader.SetGlobalInt("Blocker_Samples", Blocker_SampleCount);
@@ -126,7 +139,9 @@ public void UpdateShaderValues ()
         else
             shadowRenderTexture.filterMode = filterMode;
 
-        Shader.SetGlobalFloat("Softness", Softness * Softness / 32f / Mathf.Sqrt(QualitySettings.shadowDistance));
+        Shader.SetGlobalFloat("Softness", Softness / 64f / Mathf.Sqrt(QualitySettings.shadowDistance));
+        Shader.SetGlobalFloat("SoftnessFalloff", Mathf.Exp(SoftnessFalloff));
+        //Shader.SetGlobalFloat("NearPlane", NearPlane);
 
         Shader.SetGlobalFloat("RECEIVER_PLANE_MIN_FRACTIONAL_ERROR", MaxStaticGradientBias);
         Shader.SetGlobalFloat("Blocker_GradientBias", Blocker_GradientBias);
@@ -153,6 +168,7 @@ public void UpdateShaderValues ()
         int maxSamples = Mathf.Max(Blocker_SampleCount, PCF_SampleCount);
 
         SetFlag("POISSON_32", maxSamples < 33);
+        SetFlag("POISSON_64", maxSamples > 33);
     }
 
     public void UpdateCommandBuffer ()
@@ -165,13 +181,7 @@ public void UpdateCommandBuffer ()
         copyShadowBuffer.Blit(BuiltinRenderTextureType.CurrentActive, shadowRenderTexture);
         copyShadowBuffer.SetGlobalTexture(shadowmapPropID, shadowRenderTexture);
     }
-
-    public void CreateShadowRenderTexture ()
-    {
-        shadowRenderTexture = new RenderTexture(resolution, resolution, 0, format);
-        shadowRenderTexture.filterMode = filterMode;
-        shadowRenderTexture.useMipMap = false;
-    } 
+    #endregion
 
     public void SetFlag (string shaderKeyword, bool value)
     {

Assets/PCSS/Demo/Demo Assets/Prefabs/Directional Light.prefab

@@ -251,6 +251,9 @@ uniform float Blocker_Rotation = .5;
 uniform float PCF_Rotation = .5;
 
 uniform float Softness = 1.0;
+uniform float SoftnessFalloff = 1.0;
+//uniform float NearPlane = .1;
+
 uniform float Blocker_GradientBias = 0.0;
 uniform float PCF_GradientBias = 1.0;
 uniform float CascadeBlendDistance = .5;
@@ -502,11 +505,15 @@ float PCF_Filter(float2 uv, float depth, float filterRadiusUV, float2 receiverPl
 =========================================================================================================================================
 */
 
-
 float PCSS_Main(float4 coords, float2 receiverPlaneDepthBias, float random)
 {
 	float2 uv = coords.xy;
 	float depth = coords.z;
+	float zAwareDepth = depth;
+
+#if defined(UNITY_REVERSED_Z)
+	zAwareDepth = 1.0 - depth;
+#endif
 
 	//float rotationAngle = random * 6.283185307179586476925286766559;
 	float rotationAngle = random * 3.1415926;
@@ -518,6 +525,7 @@ float PCSS_Main(float4 coords, float2 receiverPlaneDepthBias, float random)
 
 	// STEP 1: blocker search
 	//float searchSize = Softness * (depth - _LightShadowData.w) / depth;
+	//float searchSize = Softness * saturate(zAwareDepth - NearPlane) / zAwareDepth;
 	float2 blockerInfo = FindBlocker(uv, depth, Softness, receiverPlaneDepthBias, rotationTrig);
 
 	if (blockerInfo.y < 1)
@@ -527,11 +535,9 @@ float PCSS_Main(float4 coords, float2 receiverPlaneDepthBias, float random)
 	}
 
 	// STEP 2: penumbra size
-#if defined(UNITY_REVERSED_Z)
-	float penumbra = (1.0 - depth) - blockerInfo.x;
-#else
-	float penumbra = depth - blockerInfo.x;
-#endif
+	//float penumbra = zAwareDepth * zAwareDepth - blockerInfo.x * blockerInfo.x;
+	float penumbra = zAwareDepth - blockerInfo.x;
+	penumbra = 1.0 - pow(1.0 - penumbra, SoftnessFalloff);
 
 	float filterRadiusUV = penumbra * Softness;
 	//filterRadiusUV *= filterRadiusUV;
@@ -584,7 +590,7 @@ fixed4 frag_pcss (v2f i) : SV_Target
 #if defined(USE_NOISE_TEX)
 	float random = tex2D(_NoiseTexture, i.uv.xy * NoiseCoords.xy * _ScreenParams.xy).a;
 	random = mad(random, 2.0, -1.0);
-	random = sign(random) * (1.0 - sqrt(1.0 - abs(random)));
+	//random = sign(random) * (1.0 - sqrt(1.0 - abs(random)));
 #else
 	float random = ValueNoise(wpos.xyz);
 #endif