add support for lighting tab ibl

add support for lighting tab ibl

Assets/ScriptableRenderLoop/fptl/FptlLighting.cs

             cmd.SetGlobalTexture("_pointCookieTextures", m_CubeCookieTexArray.GetTexCache());
             cmd.SetGlobalTexture("_reflCubeTextures", m_CubeReflTexArray.GetTexCache());
 
+            var topCube = ReflectionProbe.GetDefaultCubemapIbl();
+            var defdecode = ReflectionProbe.CalculateHDRDecodeValuesForDefaultTexture();
+            cmd.SetGlobalTexture("_reflRootCubeTexture", topCube);
+            cmd.SetGlobalFloat("_reflRootHdrDecodeMult", defdecode.x);
+            cmd.SetGlobalFloat("_reflRootHdrDecodeExp", defdecode.y);
+
             if (enableClustered)
             {
                 cmd.SetGlobalFloat("g_fClustScale", m_ClustScale);

Assets/ScriptableRenderLoop/fptl/ReflectionTemplate.hlsl

 
 
 UNITY_DECLARE_TEXCUBEARRAY(_reflCubeTextures);
+UNITY_DECLARE_TEXCUBE(_reflRootCubeTexture);
+//uniform int _reflRootSliceIndex;
+uniform float _reflRootHdrDecodeMult;
+uniform float _reflRootHdrDecodeExp;
+
 
 half3 Unity_GlossyEnvironment (UNITY_ARGS_TEXCUBEARRAY(tex), int sliceIndex, half4 hdr, Unity_GlossyEnvironmentData glossIn);
 
     light.dir = 0;
 
     float3 ints = 0;
+
+	// root ibl begin
+	{
+		Unity_GlossyEnvironmentData g;
+		g.roughness = percRoughness;
+		g.reflUVW = worldNormalRefl;
+
+		half3 env0 = Unity_GlossyEnvironment(UNITY_PASS_TEXCUBE(_reflRootCubeTexture), float4(_reflRootHdrDecodeMult, _reflRootHdrDecodeExp, 0.0, 0.0), g);
+		//half3 env0 = Unity_GlossyEnvironment(UNITY_PASS_TEXCUBEARRAY(_reflCubeTextures), _reflRootSliceIndex, float4(_reflRootHdrDecodeMult, _reflRootHdrDecodeExp, 0.0, 0.0), g);
+
+		UnityIndirect ind;
+		ind.diffuse = 0;
+		ind.specular = env0;// * data.occlusion;
+		ints = EvalIndirectSpecular(light, ind);
+	}
+	// root ibl end
 
     uint l=0;
 	// don't need the outer loop since the probes are sorted by volume type (currently one type in fact)