fix PR comments

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Decal/DecalProjectorComponent.cs

     [ExecuteInEditMode]
     public class DecalProjectorComponent : MonoBehaviour
     {
-        private static readonly int m_WorldToDecal = Shader.PropertyToID("_WorldToDecal");
-        private static readonly int m_DecalToWorldR = Shader.PropertyToID("_DecalToWorldR");
-
         public Material m_Material = null;
         private Material m_OldMaterial = null;
         public const int kInvalidIndex = -1;

ScriptableRenderPipeline/HDRenderPipeline/HDRP/ShaderPass/ShaderPassDBuffer.hlsl

 	float d = LOAD_TEXTURE2D(_MainDepthTexture, posInput.positionSS).x;
 	UpdatePositionInput(d, UNITY_MATRIX_I_VP, UNITY_MATRIX_VP, posInput);
 
+	// calling absolute position only to go in decal space, so there is no loss of precision here
 	float3 positionWS = GetAbsolutePositionWS(posInput.positionWS);
 	float3 positionDS = mul(UNITY_MATRIX_I_M, float4(positionWS, 1.0f)).xyz;
 	positionDS = positionDS * float3(1.0f, -1.0f, 1.0f) + float3(0.5f, 0.0f, 0.5f);