[ScreenSpaceTracing] fixed dirVS, added debugs

ScriptableRenderPipeline/Core/CoreRP/ShaderLibrary/ScreenSpaceRaymarching.hlsl

     const int MAX_ITERATIONS = 32;
 
     float4 startPositionCS = mul(projectionMatrix, float4(startPositionVS, 1));
-    float4 dirCS = mul(projectionMatrix, float4(dirVS, 0));
+    float4 dirCS = mul(projectionMatrix, float4(dirVS, 1));
 #if UNITY_UV_STARTS_AT_TOP
     // Our clip space is correct, but the NDC is flipped.
     // Conceptually, it should be (positionNDC.y = 1.0 - positionNDC.y), but this is more efficient.
 
     float2 startPositionNDC = (startPositionCS.xy * rcp(startPositionCS.w)) * 0.5 + 0.5;
     // store linear depth in z
-    float3 dirNDC = float3(normalize((dirCS.xy * rcp(dirCS.w)) * 0.5 + 0.5), -dirVS.z /*RHS convention for VS*/);
+    float l = length(dirCS.xy);
+    float3 dirNDC = dirCS.xyz / l;
+
     float2 invDirNDC = 1 / dirNDC.xy;
     int2 cellPlanes = clamp(sign(dirNDC.xy), 0, 1);
 
 
     int currentLevel = minLevel;
-    int2 cellCount = bufferSize >> minLevel;
+    int2 cellCount = bufferSize >> currentLevel;
     int2 cellSize = int2(1 / float2(cellCount));
 
     // store linear depth in z
             hit.distance += rayOffsetLength;
             --currentLevel;
         }
+
+        cellCount = bufferSize >> currentLevel;
+        cellSize = int2(1 / float2(cellCount));
     }
 
     hit.linearDepth = positionTXS.z;
             case DEBUGSCREENSPACETRACING_POSITION_NDC:
                 hit.debugOutput = float3(startPositionNDC.xy, 0);
                 break;
+            case DEBUGSCREENSPACETRACING_DIR_VS:
+                hit.debugOutput = dirVS * 0.5 + 0.5;
+                break;
-                hit.debugOutput = dirNDC;
+                hit.debugOutput = float3(dirNDC.xy * 0.5 + 0.5, dirNDC.z);
                 break;
             case DEBUGSCREENSPACETRACING_HIT_DISTANCE:
                 hit.debugOutput = hit.distance;

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Debug/LightingDebug.cs

     {
         None,
         PositionNDC,
+        DirVS,
         DirNDC,
         HitDistance,
         HitDepth,

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Debug/LightingDebug.cs.hlsl

 //
 #define DEBUGSCREENSPACETRACING_NONE (0)
 #define DEBUGSCREENSPACETRACING_POSITION_NDC (1)
-#define DEBUGSCREENSPACETRACING_DIR_NDC (2)
-#define DEBUGSCREENSPACETRACING_HIT_DISTANCE (3)
-#define DEBUGSCREENSPACETRACING_HIT_DEPTH (4)
-#define DEBUGSCREENSPACETRACING_HIT_SUCCESS (5)
-#define DEBUGSCREENSPACETRACING_ITERATION_COUNT (6)
-#define DEBUGSCREENSPACETRACING_MAX_USED_LEVEL (7)
+#define DEBUGSCREENSPACETRACING_DIR_VS (2)
+#define DEBUGSCREENSPACETRACING_DIR_NDC (3)
+#define DEBUGSCREENSPACETRACING_HIT_DISTANCE (4)
+#define DEBUGSCREENSPACETRACING_HIT_DEPTH (5)
+#define DEBUGSCREENSPACETRACING_HIT_SUCCESS (6)
+#define DEBUGSCREENSPACETRACING_ITERATION_COUNT (7)
+#define DEBUGSCREENSPACETRACING_MAX_USED_LEVEL (8)
 
 
 #endif