Automatically bake .ghx files to .ply

Grasshopper
1

Hello friends,

I have many thousands of .ghx files and I need to convert them into .ply files. The manual workflow would be to open Grasshopper, bake the component to Rhino and then saveAs file.ply.

However, as I have thousands of files and will have thousands more in the future, a manual approach is not feasible.
What would be the best was to automate this?

Thanks a lot.

2

Probably easiest to create a C# script (or VB or Python) inside Grasshopper. You give this script a folder or list of filenames, it loads them all, runs them all, bakes them all, then unloads the ghx files, selects the geometry and runs the Export command.

Is there a good rule for which parameters in the ghx files contain the meshes you wish to bake?

3

This is not great in terms of automation, but it may get you started: processor.gh (2.8 KB)

As per usual there is some juggling involved trying to do things from within a solution (which is where the RunScript() method runs). So I have to create a form with a button which allows the process to run starting from a UI event instead.

  private void RunScript()
  {
    var form = new System.Windows.Forms.Form();
    form.ShowInTaskbar = false;
    form.Text = "PLY Process";
    form.MinimizeBox = false;
    form.MaximizeBox = false;
    form.Size = new System.Drawing.Size(200, 200);

    var button = new System.Windows.Forms.Button();
    button.Dock = System.Windows.Forms.DockStyle.Fill;
    button.Text = "Run!";
    button.Click += ButtonClick;

    form.Controls.Add(button);
    form.Show(Grasshopper.Instances.DocumentEditor);
  }

  // <Custom additional code> 
  private void ButtonClick(object sender, EventArgs e)
  {
    System.Windows.Forms.OpenFileDialog dlg = new System.Windows.Forms.OpenFileDialog();
    dlg.Filter = "Grasshopper Files|*.gh;*.ghx";
    dlg.Multiselect = true;

    if (dlg.ShowDialog(Grasshopper.Instances.DocumentEditor) != System.Windows.Forms.DialogResult.OK)
      return;

    var names = dlg.FileNames;
    foreach (var name in names)
      LoadAndBakeAndExportFile(name);
  }

  private void LoadAndBakeAndExportFile(string ghxFile)
  {
    var editor = Grasshopper.Instances.DocumentEditor;
    if (!editor.ScriptAccess_OpenDocument(ghxFile))
      return;

    var doc = Grasshopper.Instances.ActiveCanvas.Document;
    doc.NewSolution(false);

    var ids = BakeFile(doc);

    Rhino.RhinoDoc.ActiveDoc.Objects.UnselectAll();
    Rhino.RhinoDoc.ActiveDoc.Objects.Select(ids);

    string folder = System.IO.Path.GetDirectoryName(ghxFile);
    string filename = System.IO.Path.GetFileNameWithoutExtension(ghxFile);
    string filepath = folder + System.IO.Path.DirectorySeparatorChar + filename + ".ply";

    string command = string.Format("-_Export \"{0}\" _Enter _Enter _Enter", filepath);
    Rhino.RhinoApp.RunScript(command, false);

    Rhino.RhinoDoc.ActiveDoc.Objects.Delete(ids, true);
    editor.ScriptAccess_CloseDocument();
  }
  private HashSet<Guid> BakeFile(GH_Document doc)
  {
    var ids = new HashSet<Guid>();
    foreach (var obj in doc.Objects)
    {
      if (obj.NickName != "Export")
        continue;

      var param = obj as Grasshopper.Kernel.Parameters.Param_Mesh;
      if (param == null)
        continue;

      foreach (IGH_Goo goo in param.VolatileData.AllData(true))
      {
        var mesh = goo as GH_Mesh;
        if (mesh == null)       continue;
        if (mesh.Value == null) continue;

        ids.Add(RhinoDocument.Objects.AddMesh(mesh.Value));
      }
    }
    return ids;
  }
1 Like
4

Thank you so much. That is very helpful!

5

Hi David,

I have one more small question. I want to only bake the object that is farthest to the right on the grasshopper canvas.
But I’m not sure how to select that component. Do you have any ideas?

6

You need to iterate over all the IGH_DocumentObjects in the document, get their attributes, get the attribute Bounds and filter for the Right property.

7

Thanks!

8

Hi David, you helped me a lot already, but I have another question.

I’m writing the whole script in Python and I’m able to load the file and identify the most right component, but I still haven’t figured out how to bake it.

Basically, I don know how to translate these two lines into Python:

var param = obj as Grasshopper.Kernel.Parameters.Param_Mesh;

ids.Add(RhinoDocument.Objects.AddMesh(mesh.Value));

Could you give me another hint?

9

Sorry, no hablo Python.