public void GenerateTerrainWithAlphamaps(HEU_SessionBase session, HEU_HoudiniAsset houdiniAsset, bool bRebuild)
		{
			if(_layers == null || _layers.Count == 0)
			{
				Debug.LogError("Unable to generate terrain due to lack of heightfield layers!");
				return;
			}

			HEU_VolumeLayer heightLayer = _layers[0];

			HAPI_VolumeInfo heightVolumeInfo = new HAPI_VolumeInfo();
			bool bResult = session.GetVolumeInfo(_ownerNode.GeoID, heightLayer._part.PartID, ref heightVolumeInfo);
			if (!bResult)
			{
				Debug.LogErrorFormat("Unable to get volume info for height layer: {0}!", heightLayer._layerName);
				return;
			}

			// Special handling of volume cache presets. It is applied here (if exists) because it might pertain to TerrainData that exists
			// in the AssetDatabase. If we don't apply here but rather create a new one, the existing file will get overwritten.
			// Applying the preset here for terrain ensures the TerrainData is reused.
			// Get the volume preset for this part
			HEU_VolumeCachePreset volumeCachePreset = houdiniAsset.GetVolumeCachePreset(_ownerNode.ObjectNode.ObjectName, _ownerNode.GeoName, TileIndex);
			if (volumeCachePreset != null)
			{
				ApplyPreset(volumeCachePreset);

				// Remove it so that it doesn't get applied when doing the recook step
				houdiniAsset.RemoveVolumeCachePreset(volumeCachePreset);
			}

			// The TerrainData and TerrainLayer files needs to be saved out if we create them. This creates the relative folder
			// path from the Asset's cache folder: {assetCache}/{geo name}/Terrain/Tile{tileIndex}/...
			string relativeFolderPath = HEU_Platform.BuildPath(_ownerNode.GeoName, HEU_Defines.HEU_FOLDER_TERRAIN, HEU_Defines.HEU_FOLDER_TILE + TileIndex);

			if (bRebuild)
			{
				// For full rebuild, re-create the TerrainData instead of using previous
				_terrainData = null;
			}

			//Debug.Log("Generating Terrain with AlphaMaps: " + (_terrainData != null ? _terrainData.name : "NONE"));
			TerrainData terrainData = _terrainData;
			Vector3 terrainOffsetPosition = Vector3.zero;

			// Look up TerrainData file via attribute if user has set it
			string terrainDataFile = HEU_GeneralUtility.GetAttributeStringValueSingle(session, _ownerNode.GeoID, heightLayer._part.PartID,
				HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TERRAINDATA_FILE_ATTR, HAPI_AttributeOwner.HAPI_ATTROWNER_PRIM);
			if (!string.IsNullOrEmpty(terrainDataFile))
			{
				TerrainData loadedTerrainData = HEU_AssetDatabase.LoadAssetAtPath(terrainDataFile, typeof(TerrainData)) as TerrainData;
				if (loadedTerrainData == null)
				{
					Debug.LogWarningFormat("TerrainData, set via attribute, not found at: {0}", terrainDataFile);
				}
				else
				{
					// In the case that the specified TerrainData belongs to another Terrain (i.e. input Terrain), 
					// make a copy of it and store it in our cache. Note that this overwrites existing TerrainData in our cache
					// because the workflow is such that attributes will always override local setting.
					string bakedTerrainPath = houdiniAsset.GetValidAssetCacheFolderPath();
					bakedTerrainPath = HEU_Platform.BuildPath(bakedTerrainPath, relativeFolderPath);
					terrainData = HEU_AssetDatabase.CopyAndLoadAssetAtAnyPath(loadedTerrainData, bakedTerrainPath, typeof(TerrainData), true) as TerrainData;
					if (terrainData == null)
					{
						Debug.LogErrorFormat("Unable to copy TerrainData from {0} for generating Terrain.", terrainDataFile);
					}
				}
			}

			// Generate the terrain and terrain data from the height layer. This applies height values.
			bResult = HEU_TerrainUtility.GenerateTerrainFromVolume(session, ref heightVolumeInfo, heightLayer._part.ParentGeoNode.GeoID,
				heightLayer._part.PartID, heightLayer._part.OutputGameObject, ref terrainData, out terrainOffsetPosition);
			if (!bResult || terrainData == null)
			{
				return;
			}

			if (_terrainData != terrainData)
			{
				_terrainData = terrainData;
				heightLayer._part.SetTerrainData(terrainData, relativeFolderPath);
			}

			heightLayer._part.SetTerrainOffsetPosition(terrainOffsetPosition);

			int terrainSize = terrainData.heightmapResolution;

			// Now process TerrainLayers and alpha maps

			// First, preprocess all layers to get heightfield arrays, converted to proper size
			List<float[]> heightFields = new List<float[]>();
			// Corresponding list of HF volume layers to process as splatmaps
			List<HEU_VolumeLayer> volumeLayersToProcess = new List<HEU_VolumeLayer>();

			int numLayers = _layers.Count;
			float minHeight = 0;
			float maxHeight = 0;
			float  heightRange = 0;
			// This skips the height layer, and processes all other layers.
			// Note that mask shouldn't be part of _layers at this point.
			for(int i = 1; i < numLayers; ++i)
			{
				float[] normalizedHF = HEU_TerrainUtility.GetNormalizedHeightmapFromPartWithMinMax(session, _ownerNode.GeoID, _layers[i]._part.PartID, 
					_layers[i]._xLength, _layers[i]._yLength, ref minHeight, ref maxHeight, ref heightRange);
				if (normalizedHF != null && normalizedHF.Length > 0)
				{
					heightFields.Add(normalizedHF);
					volumeLayersToProcess.Add(_layers[i]);
				}
			}

			int numVolumeLayers = volumeLayersToProcess.Count;

			HAPI_NodeId geoID;
			HAPI_PartId partID;

			Texture2D defaultTexture = LoadDefaultSplatTexture();

#if UNITY_2018_3_OR_NEWER

			// Create or update the terrain layers based on heightfield layers.

			// Keep existing TerrainLayers, and either update or append to them
			TerrainLayer[] existingTerrainLayers = terrainData.terrainLayers;

			// Total layers are existing layers + new alpha maps
			List<TerrainLayer> finalTerrainLayers = new List<TerrainLayer>(existingTerrainLayers);

			// This holds the alpha map indices for each layer that will be added to the TerrainData.
			// The alpha maps could be a mix of existing and new values, so need to know which to use
			// Initially set to use existing alpha maps, then override later on if specified via HF layers
			List<int> alphaMapIndices = new List<int>();
			for (int a = 0; a < existingTerrainLayers.Length; ++a)
			{
				// Negative indices for existing alpha map (offset by -1)
				alphaMapIndices.Add(-a - 1);
			}

			bool bNewTerrainLayer = false;
			HEU_VolumeLayer layer = null;
			TerrainLayer terrainLayer = null;
			bool bSetTerrainLayerProperties = true;
			for (int m = 0; m < numVolumeLayers; ++m)
			{
				bNewTerrainLayer = false;
				bSetTerrainLayerProperties = true;

				layer = volumeLayersToProcess[m];

				geoID = _ownerNode.GeoID;
				partID = layer._part.PartID;

				terrainLayer = null;

				int terrainLayerIndex = -1;

				// The TerrainLayer attribute overrides existing TerrainLayer. So if its set, load and use it.
				string terrainLayerFile = HEU_GeneralUtility.GetAttributeStringValueSingle(session, geoID, partID,
						HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TERRAINLAYER_FILE_ATTR, HAPI_AttributeOwner.HAPI_ATTROWNER_PRIM);
				if (!string.IsNullOrEmpty(terrainLayerFile))
				{
					terrainLayer = HEU_AssetDatabase.LoadAssetAtPath(terrainLayerFile, typeof(TerrainLayer)) as TerrainLayer;
					if (terrainLayer == null)
					{
						Debug.LogWarningFormat("TerrainLayer, set via attribute, not found at: {0}", terrainLayerFile);
						// Not earlying out or skipping this layer due to error because we want to keep proper indexing
						// by creating a new TerrainLayer.
					}
					else
					{
						// TerrainLayer loaded from attribute. 
						// It could be an existing TerrainLayer that is already part of finalTerrainLayers 
						// or could be a new one which needs to be added.

						// If its a different TerrainLayer than existing, update the finalTerrainLayers, and index.
						if (layer._terrainLayer != null && layer._terrainLayer != terrainLayer)
						{
							terrainLayerIndex = HEU_TerrainUtility.GetTerrainLayerIndex(layer._terrainLayer, existingTerrainLayers);
							if (terrainLayerIndex >= 0)
							{
								finalTerrainLayers[terrainLayerIndex] = terrainLayer;
							}
						}

						if (terrainLayerIndex == -1)
						{
							// Always check if its part of existing list so as not to add it again
							terrainLayerIndex = HEU_TerrainUtility.GetTerrainLayerIndex(terrainLayer, existingTerrainLayers);
						}
					}
				}

				// No terrain layer specified, so try using existing if we have it
				if (terrainLayer == null)
				{
					terrainLayerIndex = HEU_TerrainUtility.GetTerrainLayerIndex(layer._terrainLayer, existingTerrainLayers);
					if (terrainLayerIndex >= 0)
					{
						// Note the terrainLayerIndex is same for finalTerrainLayers as existingTerrainLayers
						terrainLayer = existingTerrainLayers[terrainLayerIndex];
					}
				}

				// Still not found, so just create a new one
				if (terrainLayer == null)
				{
					terrainLayer = new TerrainLayer();
					terrainLayer.name = layer._layerName;
					//Debug.LogFormat("Created new TerrainLayer with name: {0} ", terrainLayer.name);
					bNewTerrainLayer = true;
				}

				if (terrainLayerIndex == -1)
				{
					// Adding to the finalTerrainLayers if this is indeed a newly created or loaded TerrainLayer
					// (i.e. isn't already part of the TerrainLayers for this Terrain).
					// Save this layer's index for later on if we make a copy.
					terrainLayerIndex = finalTerrainLayers.Count;
					finalTerrainLayers.Add(terrainLayer);

					// Positive index for alpha map from heightfield (starting at 1)
					alphaMapIndices.Add(m + 1);
				}
				else
				{
					// Positive index for alpha map from heightfield (starting at 1)
					alphaMapIndices[terrainLayerIndex] = m + 1;
				}

				// For existing TerrainLayer, make a copy of it if it has custom layer attributes
				// because we don't want to change the original TerrainLayer.
				if (!bNewTerrainLayer && layer._hasLayerAttributes)
				{
					string bakedTerrainPath = houdiniAsset.GetValidAssetCacheFolderPath();
					bakedTerrainPath = HEU_Platform.BuildPath(bakedTerrainPath, relativeFolderPath);
					TerrainLayer prevTerrainLayer = terrainLayer;
					terrainLayer = HEU_AssetDatabase.CopyAndLoadAssetAtAnyPath(terrainLayer, bakedTerrainPath, typeof(TerrainLayer), true) as TerrainLayer;
					if (terrainLayer != null)
					{
						// Update the TerrainLayer reference in the list with this copy
						finalTerrainLayers[terrainLayerIndex] = terrainLayer;
					}
					else
					{
						Debug.LogErrorFormat("Unable to copy TerrainLayer '{0}' for generating Terrain. "
							+ "Using original TerrainLayer. Will not be able to set any TerrainLayer properties.", layer._layerName);
						terrainLayer = prevTerrainLayer;
						bSetTerrainLayerProperties = false;
						// Again, continuing on to keep proper indexing.
					}
				}

				// Now override layer properties if they have been set via attributes
				if (bSetTerrainLayerProperties)
				{
					LoadLayerPropertiesFromAttributes(session, geoID, partID, terrainLayer, bNewTerrainLayer, defaultTexture);
				}

				if (bNewTerrainLayer)
				{
					// In order to retain the new TerrainLayer, it must be saved to the AssetDatabase.
					Object savedObject = null;
					string layerFileNameWithExt = terrainLayer.name;
					if (!layerFileNameWithExt.EndsWith(HEU_Defines.HEU_EXT_TERRAINLAYER))
					{
						layerFileNameWithExt += HEU_Defines.HEU_EXT_TERRAINLAYER;
					}
					houdiniAsset.AddToAssetDBCache(layerFileNameWithExt, terrainLayer, relativeFolderPath, ref savedObject);
				}

				// Store reference
				layer._terrainLayer = terrainLayer;
			}

			// Get existing alpha maps so we can reuse the values if needed
			float[,,] existingAlphaMaps = terrainData.GetAlphamaps(0, 0, terrainData.alphamapWidth, terrainData.alphamapHeight);

			terrainData.terrainLayers = finalTerrainLayers.ToArray();

			int numTotalAlphaMaps = finalTerrainLayers.Count;

#else
			// Create or update the SplatPrototype based on heightfield layers.

			// Need to create or reuse SplatPrototype for each layer in heightfield, representing the textures.
			SplatPrototype[] existingSplats = terrainData.splatPrototypes;

			// A full rebuild clears out existing splats, but a regular cook keeps them.
			List<SplatPrototype> finalSplats = new List<SplatPrototype>(existingSplats);

			// This holds the alpha map indices for each layer that will be added to the TerrainData
			// The alpha maps could be a mix of existing and new values, so need to know which to use
			List<int> alphaMapIndices = new List<int>();

			// Initially set to use existing alpha maps, then override later on if specified via HF layers.
			for (int a = 0; a < existingSplats.Length; ++a)
			{
				// Negative indices for existing alpha map (offset by -1)
				alphaMapIndices.Add(-a - 1);
			}

			bool bNewSplat = false;
			HEU_VolumeLayer layer = null;
			SplatPrototype splatPrototype = null;

			for (int m = 0; m < numVolumeLayers; ++m)
			{
				bNewSplat = false;

				layer = volumeLayersToProcess[m];

				geoID = _ownerNode.GeoID;
				partID = layer._part.PartID;

				// Try to find existing SplatPrototype for reuse. But not for full rebuild.
				splatPrototype = null;
				if (layer._splatPrototypeIndex >= 0 && layer._splatPrototypeIndex < existingSplats.Length)
				{
					splatPrototype = existingSplats[layer._splatPrototypeIndex];

					// Positive index for alpha map from heightfield (starting at 1)
					alphaMapIndices[layer._splatPrototypeIndex] = m + 1;
				}

				if (splatPrototype == null)
				{
					splatPrototype = new SplatPrototype();
					layer._splatPrototypeIndex = finalSplats.Count;
					finalSplats.Add(splatPrototype);

					// Positive index for alpha map from heightfield (starting at 1)
					alphaMapIndices.Add(m + 1);
				}

				// Now override splat properties if they have been set via attributes
				LoadLayerPropertiesFromAttributes(session, geoID, partID, splatPrototype, bNewSplat, defaultTexture);
			}

			// On regular cook, get existing alpha maps so we can reuse the values if needed.
			float[,,] existingAlphaMaps = terrainData.GetAlphamaps(0, 0, terrainData.alphamapWidth, terrainData.alphamapHeight);

			terrainData.splatPrototypes = finalSplats.ToArray();

			int numTotalAlphaMaps = finalSplats.Count;
#endif

			// Set alpha maps by combining with existing alpha maps, and appending new heightfields

			float[,,] alphamap = null;
			if (numTotalAlphaMaps > 0 && volumeLayersToProcess.Count > 0)
			{
				// Convert the heightfields into alpha maps with layer strengths
				float[] strengths = new float[volumeLayersToProcess.Count];
				for (int m = 0; m < volumeLayersToProcess.Count; ++m)
				{
					strengths[m] = volumeLayersToProcess[m]._strength;
				}

				alphamap = HEU_TerrainUtility.AppendConvertedHeightFieldToAlphaMap(
					volumeLayersToProcess[0]._xLength, volumeLayersToProcess[0]._yLength, existingAlphaMaps,
					heightFields, strengths, alphaMapIndices);

				// Update the alphamap resolution to the actual size of the first 
				// heightfield layer used for the alphamaps.
				// Setting the size before setting the alphamas applies proper scaling.
				int alphamapResolution = volumeLayersToProcess[0]._xLength;
				terrainData.alphamapResolution = alphamapResolution;

				terrainData.SetAlphamaps(0, 0, alphamap);
			}

			// Tree instances for scattering
			HEU_TerrainUtility.ApplyScatter(terrainData, _scatterTrees);

			// If the layers were writen out, this saves the asset DB. Otherwise user has to save it themselves.
			// Not 100% sure this is needed, but without this the editor doesn't know the terrain asset has been updated
			// and therefore doesn't import and show the terrain layer.
			HEU_AssetDatabase.SaveAssetDatabase();
		}
示例#2
0
		public bool GenerateTerrainBuffers(HEU_SessionBase session, HAPI_NodeId nodeID, List<HAPI_PartInfo> volumeParts,
			List<HAPI_PartInfo> scatterInstancerParts, out List<HEU_LoadBufferVolume> volumeBuffers)
		{
			volumeBuffers = null;
			if (volumeParts.Count == 0)
			{
				return true;
			}

			volumeBuffers = new List<HEU_LoadBufferVolume>();

			int numParts = volumeParts.Count;
			for (int i = 0; i < numParts; ++i)
			{
				HAPI_VolumeInfo volumeInfo = new HAPI_VolumeInfo();
				bool bResult = session.GetVolumeInfo(nodeID, volumeParts[i].id, ref volumeInfo);
				if (!bResult || volumeInfo.tupleSize != 1 || volumeInfo.zLength != 1 || volumeInfo.storage != HAPI_StorageType.HAPI_STORAGETYPE_FLOAT)
				{
					SetLog(HEU_LoadData.LoadStatus.ERROR, "This heightfield is not supported. Please check documentation.");
					return false;
				}

				if (volumeInfo.xLength != volumeInfo.yLength)
				{
					SetLog(HEU_LoadData.LoadStatus.ERROR, "Non-square sized terrain not supported.");
					return false;
				}

				string volumeName = HEU_SessionManager.GetString(volumeInfo.nameSH, session);
				bool bHeightPart = volumeName.Equals(HEU_Defines.HAPI_HEIGHTFIELD_LAYERNAME_HEIGHT);
				bool bMaskPart = volumeName.Equals(HEU_Defines.HAPI_HEIGHTFIELD_LAYERNAME_MASK);

				//Debug.LogFormat("Part name: {0}, GeoName: {1}, Volume Name: {2}, Display: {3}", part.PartName, geoNode.GeoName, volumeName, geoNode.Displayable);

				// Ignoring mask layer because it is Houdini-specific (same behaviour as regular HDA terrain generation)
				if (bMaskPart)
				{
					continue;
				}

				HEU_LoadBufferVolumeLayer layer = new HEU_LoadBufferVolumeLayer();
				layer._layerName = volumeName;
				layer._partID = volumeParts[i].id;
				layer._heightMapWidth = volumeInfo.xLength;
				layer._heightMapHeight = volumeInfo.yLength;

				Matrix4x4 volumeTransformMatrix = HEU_HAPIUtility.GetMatrixFromHAPITransform(ref volumeInfo.transform, false);
				layer._position = HEU_HAPIUtility.GetPosition(ref volumeTransformMatrix);
				Vector3 scale = HEU_HAPIUtility.GetScale(ref volumeTransformMatrix);

				// Calculate real terrain size in both Houdini and Unity.
				// The height values will be mapped over this terrain size.
				float gridSpacingX = scale.x * 2f;
				float gridSpacingY = scale.y * 2f;
				layer._terrainSizeX = Mathf.Round((volumeInfo.xLength - 1) * gridSpacingX);
				layer._terrainSizeY = Mathf.Round((volumeInfo.yLength - 1) * gridSpacingY);

				// Get volume bounds for calculating position offset
				session.GetVolumeBounds(nodeID, volumeParts[i].id, 
					out layer._minBounds.x, out layer._minBounds.y, out layer._minBounds.z, 
					out layer._maxBounds.x, out layer._maxBounds.y, out layer._maxBounds.z, 
					out layer._center.x, out layer._center.y, out layer._center.z);

				// Look up TerrainLayer file via attribute if user has set it
				layer._layerPath = HEU_GeneralUtility.GetAttributeStringValueSingle(session, nodeID, volumeParts[i].id,
					HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TERRAINLAYER_FILE_ATTR, HAPI_AttributeOwner.HAPI_ATTROWNER_PRIM);

				LoadStringFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TEXTURE_DIFFUSE_ATTR, ref layer._diffuseTexturePath);
				LoadStringFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TEXTURE_MASK_ATTR, ref layer._maskTexturePath);
				LoadStringFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TEXTURE_NORMAL_ATTR, ref layer._normalTexturePath);

				LoadFloatFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_NORMAL_SCALE_ATTR, ref layer._normalScale);
				LoadFloatFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_METALLIC_ATTR, ref layer._metallic);
				LoadFloatFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_SMOOTHNESS_ATTR, ref layer._smoothness);

				LoadLayerColorFromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_SPECULAR_ATTR, ref layer._specularColor);
				LoadLayerVector2FromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TILE_OFFSET_ATTR, ref layer._tileOffset);
				LoadLayerVector2FromAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TILE_SIZE_ATTR, ref layer._tileSize);

				// Get the height values from Houdini along with the min and max height range.
				layer._normalizedHeights = HEU_TerrainUtility.GetNormalizedHeightmapFromPartWithMinMax(_session, nodeID, volumeParts[i].id, volumeInfo.xLength, volumeInfo.yLength, ref layer._minHeight, ref layer._maxHeight, ref layer._heightRange);

				// Get the tile index, if it exists, for this part
				HAPI_AttributeInfo tileAttrInfo = new HAPI_AttributeInfo();
				int[] tileAttrData = new int[0];
				HEU_GeneralUtility.GetAttribute(session, nodeID, volumeParts[i].id, HEU_Defines.HAPI_HEIGHTFIELD_TILE_ATTR, ref tileAttrInfo, ref tileAttrData, session.GetAttributeIntData);

				int tileIndex = 0;
				if (tileAttrInfo.exists && tileAttrData.Length == 1)
				{
					tileIndex = tileAttrData[0];
				}

				// Add layer based on tile index
				if (tileIndex >= 0)
				{
					HEU_LoadBufferVolume volumeBuffer = null;
					for(int j = 0; j < volumeBuffers.Count; ++j)
					{
						if (volumeBuffers[j]._tileIndex == tileIndex)
						{
							volumeBuffer = volumeBuffers[j];
							break;
						}
					}

					if (volumeBuffer == null)
					{
						volumeBuffer = new HEU_LoadBufferVolume();
						volumeBuffer.InitializeBuffer(volumeParts[i].id, volumeName, false, false);

						volumeBuffer._tileIndex = tileIndex;
						volumeBuffers.Add(volumeBuffer);
					}

					if (bHeightPart)
					{
						// Height layer always first layer
						volumeBuffer._layers.Insert(0, layer);

						volumeBuffer._heightMapWidth = layer._heightMapWidth;
						volumeBuffer._heightMapHeight = layer._heightMapHeight;
						volumeBuffer._terrainSizeX = layer._terrainSizeX;
						volumeBuffer._terrainSizeY = layer._terrainSizeY;
						volumeBuffer._heightRange = (layer._maxHeight - layer._minHeight);

						// Look up TerrainData file path via attribute if user has set it
						volumeBuffer._terrainDataPath = HEU_GeneralUtility.GetAttributeStringValueSingle(session, nodeID, volumeBuffer._id,
							HEU_Defines.DEFAULT_UNITY_HEIGHTFIELD_TERRAINDATA_FILE_ATTR, HAPI_AttributeOwner.HAPI_ATTROWNER_PRIM);

						// Load the TreePrototype buffers
						List<HEU_TreePrototypeInfo> treePrototypeInfos = HEU_TerrainUtility.GetTreePrototypeInfosFromPart(session, nodeID, volumeBuffer._id);
						if (treePrototypeInfos != null)
						{
							if (volumeBuffer._scatterTrees == null)
							{
								volumeBuffer._scatterTrees = new HEU_VolumeScatterTrees();
							}
							volumeBuffer._scatterTrees._treePrototypInfos = treePrototypeInfos;
						}

					}
					else
					{
						volumeBuffer._layers.Add(layer);
					}
				}

				Sleep();
			}

			// Each volume buffer is a self contained terrain tile
			foreach(HEU_LoadBufferVolume volumeBuffer in volumeBuffers)
			{
				List<HEU_LoadBufferVolumeLayer> layers = volumeBuffer._layers;
				//Debug.LogFormat("Heightfield: tile={0}, layers={1}", tile._tileIndex, layers.Count);

				int heightMapWidth = volumeBuffer._heightMapWidth;
				int heightMapHeight = volumeBuffer._heightMapHeight;

				int numLayers = layers.Count;
				if (numLayers > 0)
				{
					// Convert heightmap values from Houdini to Unity
					volumeBuffer._heightMap = HEU_TerrainUtility.ConvertHeightMapHoudiniToUnity(heightMapWidth, heightMapHeight, layers[0]._normalizedHeights);

					Sleep();

					// Convert splatmap values from Houdini to Unity.
					// Start at 2nd index since height is strictly for height values (not splatmap).
					List<float[]> heightFields = new List<float[]>();
					for(int m = 1; m < numLayers; ++m)
					{
						heightFields.Add(layers[m]._normalizedHeights);
					}

					// The number of maps are the number of splatmaps (ie. non height/mask layers)
					int numMaps = heightFields.Count;
					if (numMaps > 0)
					{
						// Using the first splatmap size for all splatmaps
						volumeBuffer._splatMaps = HEU_TerrainUtility.ConvertHeightFieldToAlphaMap(layers[1]._heightMapWidth, layers[1]._heightMapHeight, heightFields);
					}
					else
					{
						volumeBuffer._splatMaps = null;
					}

					volumeBuffer._position = new Vector3((volumeBuffer._terrainSizeX + volumeBuffer._layers[0]._minBounds.x), volumeBuffer._layers[0]._minHeight + volumeBuffer._layers[0]._position.y, volumeBuffer._layers[0]._minBounds.z);
				}
			}

			// Process the scatter instancer parts to get the scatter data
			for (int i = 0; i < scatterInstancerParts.Count; ++i)
			{
				// Find the terrain tile (use primitive attr). Assume 0 tile if not set (i.e. not split into tiles)
				int terrainTile = 0;
				HAPI_AttributeInfo tileAttrInfo = new HAPI_AttributeInfo();
				int[] tileAttrData = new int[0];
				if (HEU_GeneralUtility.GetAttribute(session, nodeID, scatterInstancerParts[i].id, HEU_Defines.HAPI_HEIGHTFIELD_TILE_ATTR, ref tileAttrInfo, ref tileAttrData, session.GetAttributeIntData))
				{
					if (tileAttrData != null && tileAttrData.Length > 0)
					{
						terrainTile = tileAttrData[0];
					}
				}

				// Find the volume layer associated with this part using the terrain tile index
				HEU_LoadBufferVolume volumeBuffer = GetLoadBufferVolumeFromTileIndex(terrainTile, volumeBuffers);
				if (volumeBuffer == null)
				{
					continue;
				}

				HEU_TerrainUtility.PopulateScatterInfo(session, nodeID, scatterInstancerParts[i].id, scatterInstancerParts[i].pointCount, ref volumeBuffer._scatterTrees);
			}

			return true;
		}