How to modify PMI text?

Visualization Solutions HOOPS Visualize Web
1

Hi,

I have a user scenario where they want to modify PMI information. Specifically, after loading a SCS file in webview, they want to modify a certain PMI text content in the file and save it in the SCS file. Can this be achieved?

2

Hello,

The short answer is no, this cannot be done. PMI is not treated as a text object, per se, in the Web Viewer. It is actually rendered as a 3D mesh. Further, changes made in the Web Viewer cannot be saved directly in the Stream Cache file itself.

Thanks,
Tino

3

OK, I understand, thanks.

4

I have a plan now. Could you please help me check if it is feasible
1: Obtain current PMI data
2: Prepare the modified mesh data
3: Delete the old PMI and create a new one

async function getMeshInstanceDataFromNode(nodeId) {  
  // 1. 获取节点的MeshData副本  
  const meshDataCopy = await viewer.model.getNodeMeshData(nodeId);  
  // 2. 将 MeshDataCopy 转换为 MeshData  
  const meshData = new Communicator.MeshData();  
  // 这里需要将 meshDataCopy 的顶点、法线、面等数据复制到 meshData  
  // 伪代码示例（具体API可能需要根据实际数据结构调整）  
  meshDataCopy.faces.forEach(face => {  
    meshData.addFaces(face.vertices, face.normals);  
  });  
  // 3. 创建Mesh，得到MeshId  
  const meshId = await viewer.model.createMesh(meshData);  
  // 4. 创建MeshInstanceData  
  const meshInstanceData = new Communicator.MeshInstanceData(meshId);  
  // 5. 设置变换矩阵（可选）  
  const matrix = viewer.model.getNodeMatrix(nodeId);  
  meshInstanceData.setMatrix(matrix);  
  return meshInstanceData;  
}

const refOnTopoItems = await viewer.model.getPmiTopologyReferences(nodeId)

async function replacePmi(oldPmiId, newMeshInstanceData, pmiType, pmiSubType, refOnTopoItems, parentNodeId) {  
  // 删除旧PMI节点  
  await viewer.model.deleteNode(oldPmiId);  
  // 创建新的PMI实例  
  const newPmiId = await viewer.model.createPmiInstance(  
    newMeshInstanceData,  
    pmiType,  
    pmiSubType,  
    refOnTopoItems,  
    parentNodeId  
  );  
  return newPmiId;  
}

The main difficulty I’m thinking of now is how to obtain the modified mesh data. For example, how to change the PMI data that was previously obtained with a value of 6 to 7, and so on

Thanks

5

Not really sure what you mean in the quote referenced above. If you’ve created a new PMI mesh, wouldn’t you have a reference to the mesh data?

6

Sorry, my previous description wasn’t very clear. The mesh data reference does exist. The main issue now is how to create a new PMI mesh, since I haven’t found a way to modify the mesh data of an existing PMI. For example, when a user wants to update the PMI’s value or text content, I’m not sure how to handle that.

7

Indeed, this is the limitation with editing text in the Web Viewer. As mentioned in one of my previous post on this thread, text is a geometrical mesh and not a text object. The mesh is composted of a points/face array and individual texts/glyphs cannot be easily identified in the array.

8

Thank you for your explanation. From what I understand, the mesh data of the PMI cannot be modified.