[MLA-16] add filter mask to ray perception (#3111)

* add filter mask to ray perception

* use LayerMask type

UnitySDK/Assets/ML-Agents/Editor/Tests/RayPerceptionTests.cs

                 tags);
             Assert.IsTrue(result.Count == angles.Length * (tags.Length + 2));
         }
+
+        [Test]
+        public void TestConstants()
+        {
+            Assert.AreEqual(Physics.DefaultRaycastLayers, Physics2D.DefaultRaycastLayers);
+        }
     }
 }

UnitySDK/Assets/ML-Agents/Scripts/Sensor/RayPerceptionSensor.cs

         float m_CastRadius;
         CastType m_CastType;
         Transform m_Transform;
+        int m_LayerMask;
 
         /// <summary>
         /// Debug information for the raycast hits. This is used by the RayPerceptionSensorComponent.
         }
 
         public RayPerceptionSensor(string name, float rayDistance, List<string> detectableObjects, float[] angles,
-            Transform transform, float startOffset, float endOffset, float castRadius, CastType castType)
+            Transform transform, float startOffset, float endOffset, float castRadius, CastType castType,
+            int rayLayerMask)
         {
             var numObservations = (detectableObjects.Count + 2) * angles.Length;
             m_Shape = new[] { numObservations };
             m_EndOffset = endOffset;
             m_CastRadius = castRadius;
             m_CastType = castType;
+            m_LayerMask = rayLayerMask;
 
             if (Application.isEditor)
             {
             {
                 PerceiveStatic(
                     m_RayDistance, m_Angles, m_DetectableObjects, m_StartOffset, m_EndOffset,
-                    m_CastRadius, m_Transform, m_CastType, m_Observations, false, m_DebugDisplayInfo
+                    m_CastRadius, m_Transform, m_CastType, m_Observations, false, m_LayerMask,
+                    m_DebugDisplayInfo
                 );
                 adapter.AddRange(m_Observations);
             }
             float startOffset, float endOffset, float castRadius,
             Transform transform, CastType castType, float[] perceptionBuffer,
             bool legacyHitFractionBehavior = false,
+            int layerMask = Physics.DefaultRaycastLayers,
             DebugDisplayInfo debugInfo = null)
         {
             Array.Clear(perceptionBuffer, 0, perceptionBuffer.Length);
                     RaycastHit rayHit;
                     if (castRadius > 0f)
                     {
-                        castHit = Physics.SphereCast(startPositionWorld, castRadius, rayDirection, out rayHit, rayLength);
+                        castHit = Physics.SphereCast(startPositionWorld, castRadius, rayDirection, out rayHit,
+                            rayLength, layerMask);
-                        castHit = Physics.Raycast(startPositionWorld, rayDirection, out rayHit, rayLength);
+                        castHit = Physics.Raycast(startPositionWorld, rayDirection, out rayHit,
+                            rayLength, layerMask);
                     }
 
                     hitFraction = castHit ? rayHit.distance / rayLength : 1.0f;
                     RaycastHit2D rayHit;
                     if (castRadius > 0f)
                     {
-                        rayHit = Physics2D.CircleCast(startPositionWorld, castRadius, rayDirection, rayLength);
+                        rayHit = Physics2D.CircleCast(startPositionWorld, castRadius, rayDirection,
+                            rayLength, layerMask);
-                        rayHit = Physics2D.Raycast(startPositionWorld, rayDirection, rayLength);
+                        rayHit = Physics2D.Raycast(startPositionWorld, rayDirection, rayLength, layerMask);
                     }
 
                     castHit = rayHit;

UnitySDK/Assets/ML-Agents/Scripts/Sensor/RayPerceptionSensorComponentBase.cs

         [Tooltip("Length of the rays to cast.")]
         public float rayLength = 20f;
 
+        [Tooltip("Controls which layers the rays can hit.")]
+        public LayerMask rayLayerMask = Physics.DefaultRaycastLayers;
+
         [Range(1, 50)]
         [Tooltip("Whether to stack previous observations. Using 1 means no previous observations.")]
         public int observationStacks = 1;
         {
             var rayAngles = GetRayAngles(raysPerDirection, maxRayDegrees);
             m_RaySensor = new RayPerceptionSensor(sensorName, rayLength, detectableTags, rayAngles,
-                transform, GetStartVerticalOffset(), GetEndVerticalOffset(), sphereCastRadius, GetCastType()
+                transform, GetStartVerticalOffset(), GetEndVerticalOffset(), sphereCastRadius, GetCastType(),
+                rayLayerMask
             );
 
             if (observationStacks != 1)

UnitySDK/ProjectSettings/ProjectVersion.txt

-m_EditorVersion: 2017.4.32f1
+m_EditorVersion: 2017.4.33f1