/// <summary>
/// Generates heightfield/terrain data from the given object relevant for uploading to Houdini.
/// </summary>
/// <param name="inputObject"></param>
/// <returns>Valid input object or null if given object is not supported</returns>
public HEU_InputDataTerrain GenerateTerrainDataFromGameObject(GameObject inputObject)
{
HEU_InputDataTerrain inputData = null;
Terrain terrain = inputObject.GetComponent<Terrain>();
if (terrain != null)
{
TerrainData terrainData = terrain.terrainData;
Vector3 terrainSize = terrainData.size;
if (terrainSize.x != terrainSize.z)
{
Debug.LogError("Only square sized terrains are supported for input! Change to square size and try again.");
return null;
}
inputData = new HEU_InputDataTerrain();
inputData._inputObject = inputObject;
inputData._terrain = terrain;
inputData._terrainData = terrainData;
// Height values in Unity are normalized between 0 and 1, so this height scale
// will multiply them before uploading to Houdini.
inputData._heightScale = terrainSize.y;
// Terrain heightMapResolution is the pixel resolution, which we set to the number of voxels
// by dividing the terrain size with it. In Houdini, this is the Grid Spacing.
inputData._voxelSize = terrainSize.x / inputData._terrainData.heightmapResolution;
// This is the number of heightfield voxels on each dimension.
inputData._numPointsX = Mathf.RoundToInt(inputData._terrainData.heightmapResolution * inputData._voxelSize);
inputData._numPointsY = Mathf.RoundToInt(inputData._terrainData.heightmapResolution * inputData._voxelSize);
Matrix4x4 transformMatrix = inputObject.transform.localToWorldMatrix;
HAPI_TransformEuler transformEuler = HEU_HAPIUtility.GetHAPITransformFromMatrix(ref transformMatrix);
// Volume transform used for all heightfield layers
inputData._transform = new HAPI_Transform(false);
// Unity terrain pivots are at bottom left, but Houdini uses centered heightfields so
// apply local position offset by half sizes and account for coordinate change
inputData._transform.position[0] = terrainSize.z * 0.5f;
inputData._transform.position[1] = -terrainSize.x * 0.5f;
inputData._transform.position[2] = 0;
// Volume scale controls final size, but requires to be divided by 2
inputData._transform.scale[0] = terrainSize.x * 0.5f;
inputData._transform.scale[1] = terrainSize.z * 0.5f;
inputData._transform.scale[2] = 0.5f;
inputData._transform.rotationQuaternion[0] = 0f;
inputData._transform.rotationQuaternion[1] = 0f;
inputData._transform.rotationQuaternion[2] = 0f;
inputData._transform.rotationQuaternion[3] = 1f;
}
return inputData;
}
/// <summary>
/// Set the input node's transform.
/// </summary>
/// <param name="session">Session that the input node exists in</param>
/// <param name="inputObject">The input object info containing data about the input</param>
/// <param name="inputNodeID">The input node ID</param>
/// <param name="bKeepWorldTransform">Whether to use world transform or not</param>
/// <returns></returns>
internal static bool UploadInputObjectTransform(HEU_SessionBase session, HEU_InputObjectInfo inputObject, HAPI_NodeId inputNodeID, bool bKeepWorldTransform)
{
Matrix4x4 inputTransform = Matrix4x4.identity;
if (inputObject._useTransformOffset)
{
if (bKeepWorldTransform)
{
// Add offset tranform to world transform
Transform inputObjTransform = inputObject._gameObject.transform;
Vector3 position = inputObjTransform.position + inputObject._translateOffset;
Quaternion rotation = inputObjTransform.rotation * Quaternion.Euler(inputObject._rotateOffset);
Vector3 scale = Vector3.Scale(inputObjTransform.localScale, inputObject._scaleOffset);
Vector3 rotVector = rotation.eulerAngles;
inputTransform = HEU_HAPIUtility.GetMatrix4x4(ref position, ref rotVector, ref scale);
}
else
{
// Offset from origin.
inputTransform = HEU_HAPIUtility.GetMatrix4x4(ref inputObject._translateOffset, ref inputObject._rotateOffset, ref inputObject._scaleOffset);
}
}
else
{
inputTransform = inputObject._gameObject.transform.localToWorldMatrix;
}
HAPI_TransformEuler transformEuler = HEU_HAPIUtility.GetHAPITransformFromMatrix(ref inputTransform);
HAPI_NodeInfo inputNodeInfo = new HAPI_NodeInfo();
if (!session.GetNodeInfo(inputNodeID, ref inputNodeInfo))
{
return false;
}
if (session.SetObjectTransform(inputNodeInfo.parentId, ref transformEuler))
{
inputObject._syncdTransform = inputTransform;
inputObject._syncdChildTransforms.Clear();
GetChildrenTransforms(inputObject._gameObject.transform, ref inputObject._syncdChildTransforms);
}
return true;
}