/// <summary>
/// Applies a Houdini's UVLayout node to each given gameobject's mesh data, and generates the output.
/// The output could be a copy gameobject, or replace the mesh and materials on the original.
/// </summary>
/// <param name="gameObjects">Array of gameobjects containing meshes</param>
/// <param name="outputMode">How the outputs should be generated</param>
/// <param name="output_name_suffix">Name to append at end of each generated gameobject if outputMode == COPY</param>
public static void ApplyUVLayoutTo(GameObject[] gameObjects, OutputMode outputMode, string output_name_suffix)
{
// A Houdini Engine session is always required. This should catch any licensing and installation issues.
HEU_SessionBase session = HEU_SessionManager.GetOrCreateDefaultSession();
if (session == null || !session.IsSessionValid())
{
Debug.LogError("Failed to get Houdini Engine session. Unable to apply UV layout.");
return;
}
if (gameObjects == null || gameObjects.Length == 0)
{
Debug.LogError("No input objects found to apply UV layout.");
return;
}
// For each gameobject with mesh:
// -create an input node in the Houdini session
// -import the mesh data into the input node
// -connect input node to a new UVLayout node
// -cook the UVLayout node
// -generate the output mesh
foreach (GameObject currentGO in gameObjects)
{
// Process the current gameobject to get the potential list of input mesh data.
// HEU_InputUtility contains helper functions for uploading mesh data into Houdini.
// Also handles LOD meshes.
bool bHasLODGroup = false;
HEU_InputInterfaceMesh inputMeshInterface = HEU_InputUtility.GetInputInterfaceByType(typeof(HEU_InputInterfaceMesh)) as HEU_InputInterfaceMesh;
HEU_InputInterfaceMesh.HEU_InputDataMeshes inputMeshes = inputMeshInterface.GenerateMeshDatasFromGameObject(currentGO);
if (inputMeshes == null || inputMeshes._inputMeshes.Count == 0)
{
Debug.LogWarningFormat("Failed to generate input mesh data for: {0}", currentGO.name);
continue;
}
// Create the input node in Houdini.
// Houdini Engine automatically creates a new object to contain the input node.
string inputName = null;
HAPI_NodeId inputNodeID = HEU_Defines.HEU_INVALID_NODE_ID;
session.CreateInputNode(out inputNodeID, inputName);
if (inputNodeID == HEU_Defines.HEU_INVALID_NODE_ID || !HEU_HAPIUtility.IsNodeValidInHoudini(session, inputNodeID))
{
Debug.LogErrorFormat("Failed to create new input node in Houdini session!");
break;
}
// Need the HAPI_NodeInfo of the new input node to get its details, such as parent object ID.
HAPI_NodeInfo nodeInfo = new HAPI_NodeInfo();
if (!session.GetNodeInfo(inputNodeID, ref nodeInfo))
{
break;
}
// Cook the node to make sure everything is alright.
if (!session.CookNode(inputNodeID, false))
{
session.DeleteNode(nodeInfo.parentId);
Debug.LogErrorFormat("New input node failed to cook!");
break;
}
// Now upload the mesh data into the input node.
if (!inputMeshInterface.UploadData(session, inputNodeID, inputMeshes))
{
session.DeleteNode(nodeInfo.parentId);
Debug.LogErrorFormat("Failed to upload input mesh data");
break;
}
// Create UVLayout node in Houdini. Passing in the input node's parent node's ID will
// create it within the same object as the input node..
HAPI_NodeId uvlayoutID = -1;
if (!session.CreateNode(nodeInfo.parentId, "uvlayout", "UVLayout", true, out uvlayoutID))
{
session.DeleteNode(nodeInfo.parentId);
break;
}
// Example showing how to set the parameter on the new UVLayout node.
session.SetParamIntValue(uvlayoutID, "correctareas", 0, 1);
// Connect the input node to the UVLayout node.
// Important bit here is the node IDs being passed in.
if (!session.ConnectNodeInput(uvlayoutID, 0, inputNodeID, 0))
{
session.DeleteNode(nodeInfo.parentId);
break;
}
// Force cook the UVLayout node in Houdini.
if (!HEU_HAPIUtility.CookNodeInHoudini(session, uvlayoutID, true, "uvlayout"))
{
session.DeleteNode(nodeInfo.parentId);
break;
}
// Now its time to generate the actual output in Unity. A couple of utlity classes will help here.
// materialCache will contain the list of materials generated..
List <HEU_MaterialData> materialCache = new List <HEU_MaterialData>();
// Suggested name of the folder within this project where output files might be written out to (eg. materials).
string assetCachePathName = "uvlayoutcache";
// First create a HEU_GenerateGeoCache which will contain the geometry data from Houdiini.
// This will get all the geometry data buffers from Houdini from the UVLayout node, along with the materials (new or existing).
HEU_GenerateGeoCache geoCache = HEU_GenerateGeoCache.GetPopulatedGeoCache(session, inputNodeID, uvlayoutID, 0, bHasLODGroup, materialCache, assetCachePathName);
if (geoCache == null)
{
session.DeleteNode(nodeInfo.parentId);
break;
}
// Store reorganized data buffers into mesh groups. Groups are created if its a LOD mesh.
List <HEU_GeoGroup> LODGroupMeshes = null;
// The default material identifier (used when no material is supplied initially in Unity).
int defaultMaterialKey = 0;
// Flag whether to generate UVs, tangents, normals in Unity (in case they weren't created in Houdini).
bool bGenerateUVs = false;
bool bGenerateTangents = false;
bool bGenerateNormals = false;
bool bPartInstanced = false;
// Now reorganize the data buffers into Unity mesh friendly format.
// This handles point splitting into vertices, collider groups, submeshes based on multiple materials, LOD groups.
// Can instead use HEU_GenerateGeoCache.GenerateGeoGroupUsingGeoCachePoints to keep as points instead.
bool bResult = HEU_GenerateGeoCache.GenerateGeoGroupUsingGeoCacheVertices(session, geoCache, bGenerateUVs, bGenerateTangents, bGenerateNormals, bHasLODGroup, bPartInstanced,
out LODGroupMeshes, out defaultMaterialKey);
if (!bResult)
{
session.DeleteNode(nodeInfo.parentId);
break;
}
// This will hold the output gameobject, along with any children and materials.
HEU_GeneratedOutput generatedOutput = new HEU_GeneratedOutput();
if (outputMode == OutputMode.COPY)
{
// For copy mode, create and set new gameobject as output
generatedOutput._outputData._gameObject = new GameObject(currentGO.name + "_HEU_modified");
}
else if (outputMode == OutputMode.REPLACE)
{
// For replace, just use current input gameobject
generatedOutput._outputData._gameObject = currentGO;
}
// Now generate the Unity meshes with material assignment. Handle LOD groups.
int numLODs = LODGroupMeshes != null ? LODGroupMeshes.Count : 0;
if (numLODs > 1)
{
bResult = HEU_GenerateGeoCache.GenerateLODMeshesFromGeoGroups(session, LODGroupMeshes, geoCache, generatedOutput, defaultMaterialKey, bGenerateUVs, bGenerateTangents, bGenerateNormals, bPartInstanced);
}
else if (numLODs == 1)
{
bResult = HEU_GenerateGeoCache.GenerateMeshFromSingleGroup(session, LODGroupMeshes[0], geoCache, generatedOutput, defaultMaterialKey, bGenerateUVs, bGenerateTangents, bGenerateNormals, bPartInstanced);
}
// Clean up by deleting the object node containing the input and uvlayout node.
session.DeleteNode(nodeInfo.parentId);
}
}
