fix dx9 shader model 3 linear rendering DoF bug

PostProcessing/Runtime/Components/DepthOfFieldComponent.cs

@@ -105,7 +105,7 @@ public void Prepare(RenderTexture source, Material uberMaterial, bool antialiasC
             material.SetFloat(Uniforms._RcpAspect, 1f / aspect);
 
             // CoC calculation pass
-            var rtCoC = context.renderTextureFactory.Get(context.width, context.height, 0, cocFormat);
+            var rtCoC = context.renderTextureFactory.Get(context.width, context.height, 0, cocFormat, RenderTextureReadWrite.Linear);
             Graphics.Blit(null, rtCoC, material, 0);
 
             if (antialiasCoC)

PostProcessing/Runtime/Utils/RenderTextureFactory.cs

@@ -27,7 +27,7 @@ public RenderTexture Get(RenderTexture baseRenderTexture)
 
         public RenderTexture Get(int width, int height, int depthBuffer = 0, RenderTextureFormat format = RenderTextureFormat.ARGBHalf, RenderTextureReadWrite rw = RenderTextureReadWrite.Default, FilterMode filterMode = FilterMode.Bilinear, TextureWrapMode wrapMode = TextureWrapMode.Clamp, string name = "FactoryTempTexture")
         {
-            var rt = RenderTexture.GetTemporary(width, height, depthBuffer, format);
+            var rt = RenderTexture.GetTemporary(width, height, depthBuffer, format, rw); // add forgotten param rw
             rt.filterMode = filterMode;
             rt.wrapMode = wrapMode;
             rt.name = name;