Supporting semantic segmentation in unity simulation.

com.unity.perception/Runtime/GroundTruth/Labelers/SemanticSegmentationLabeler.cs

 
         const string k_SemanticSegmentationDirectory = "SemanticSegmentation";
         const string k_SegmentationFilePrefix = "segmentation_";
+        string m_SemanticSegmentationDirectory;
 
         /// <summary>
         /// The id to associate with semantic segmentation annotations in the dataset.
 
             targetTexture.Create();
             targetTexture.name = "Labeling";
+            m_SemanticSegmentationDirectory = k_SemanticSegmentationDirectory + Guid.NewGuid();
 
 #if HDRP_PRESENT
             var gameObject = perceptionCamera.gameObject;
             if (!m_AsyncAnnotations.TryGetValue(frameCount, out var annotation))
                 return;
 
-            var datasetRelativePath = $"{k_SemanticSegmentationDirectory}/{k_SegmentationFilePrefix}{frameCount}.png";
-            var localPath = $"{Manager.Instance.GetDirectoryFor(k_SemanticSegmentationDirectory)}/{k_SegmentationFilePrefix}{frameCount}.png";
+            var datasetRelativePath = $"{m_SemanticSegmentationDirectory}/{k_SegmentationFilePrefix}{frameCount}.png";
+            var localPath = $"{Manager.Instance.GetDirectoryFor(m_SemanticSegmentationDirectory)}/{k_SegmentationFilePrefix}{frameCount}.png";
 
             annotation.ReportFile(datasetRelativePath);
 

com.unity.perception/Runtime/GroundTruth/SemanticSegmentationCrossPipelinePass.cs

         protected override void ExecutePass(ScriptableRenderContext renderContext, CommandBuffer cmd, Camera camera, CullingResults cullingResult)
         {
             if (s_LastFrameExecuted == Time.frameCount)
-            {
-                Debug.LogError("Semantic segmentation was run twice in the same frame. Multiple semantic segmentations are not currently supported.");
-            }
+                return;
 
             s_LastFrameExecuted = Time.frameCount;
             var renderList = CreateRendererListDesc(camera, cullingResult, "FirstPass", 0, m_OverrideMaterial, -1);