GetDataTree fro a DataTree<Point3d>

I know I'm missing something obvious, but I can't find a solution for this.

My input is a DataTree<Point3d> and I'm declaring it with:

pManager.AddPointParameter("Points", "P", "Tree of Points", GH_ParamAccess.tree );

Then to retrive data I tried using:

if (!DA.GetDataTree<Point3d>(0, out pnt)) return;

but it doesn't work, so I tried using:

Grasshopper.Kernel.Data.GH_Structure<Grasshopper.Kernel.Types.GH_Point> pnt = new Grasshopper.Kernel.Data.GH_Structure<Grasshopper.Kernel.Types.GH_Point>();

if (!DA.GetDataTree(0, out pnt)) return;

It works, but then how can I convert the GH_point to Point3d? Actually to DataTree<Point3d>?

Replies to This Discussion

Permalink Reply by Marios Tsiliakos on July 13, 2014 at 9:31am

Hi Lorenzo,

While doing whatever is your doing with your point_3D you have to cast them back to GH_points in order to be capable of being streamed out of the GH component.

You can use the GH_convert function for that.

Best,

Permalink Reply by Lorenzo Greco on July 13, 2014 at 10:28am

Hi Marios thanks for your help!

I'm trying but it doesn't work.. can you give me an example?

EDIT:

I'm also trying to output a list<Point3d> but with no success. GH returns me an error saying it couldn't convert data of type GH_Point :/

Permalink Reply by Marios Tsiliakos on July 13, 2014 at 10:47am

Your output has to be a GH_structure<GH Point> or similarly.

and your conversion line should be something like

bool (a boolean to see whether the conversion was successful or not) = GH_Convert.ToGHPoint("yourpoint3d", GH_Conversion.Both, "YourNewGHPoint")

Not tested, but if I remember correctly it's like this.

Best,

Permalink Reply by Lorenzo Greco on July 14, 2014 at 12:59pm

Sorry, maybe I don't get it. I have this situation, why isn't it working?

protected override void RegisterOutputParams(GH_Component.GH_OutputParamManager pManager)
{
pManager.AddMeshParameter("Mesh", "M", "Mesh", GH_ParamAccess.item);

}

protected override void SolveInstance(IGH_DataAccess DA)
{

DataTree<Point3d> pnts = new DataTree<Point3d>();

Grasshopper.Kernel.Data.GH_Structure<Grasshopper.Kernel.Types.GH_Point> GH_pnts = new Grasshopper.Kernel.Data.GH_Structure<Grasshopper.Kernel.Types.GH_Point>();

if (!DA.GetDataTree(0, out GH_pnts)) return;

bool myBool = GH_Convert.ToGHPoint(GH_pnts, GH_Conversion.Both, pnts);

// the following doesn't work either

// bool gno = GH_Convert.ToPoint3d(GH_pnts, pnts, GH_Conversion.Both);

....

}

Permalink Reply by Marios Tsiliakos on July 14, 2014 at 3:53pm

Have you set up the bebugger?

Why is The conversion is after the output?
You are trying to convert a gh_structure rather than a point its self. You have to iterate through your data.

Some possible reasons.

Look at the errors that vs is displaying

Permalink Reply by David Rutten on July 15, 2014 at 1:12am