Grasshopper - hatch pattern bug

Grasshopper
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1

Hi all,

I think I have noticed small bug in GH Hatch component.

We are attempting to create hatch and then bake it using custom bake component using “Rhino.RhinoDoc.ActiveDoc.Objects.AddHatch()” and even though the hatch in GH seems to be valid and passes .IsValid check, it refuses to be added into Rhino and the guid returned from the Addhatch() method is always 00000000-0000-0000-0000-000000000000.

Then I tried to do the same Hatch with EleFront and I was able to bake it, so I started tracking what the difference between the two hatches could be. It turns out that Rhino hatch component in my case somehow fails to save the pattern index into the hatch properties (PatternIndex = -1), even though the input “Hp” is valid model hatch. Selecting for instance “Solid” via right-click input menu does not help either.

Could this be the reason why I am not able to AddHatch() to Rhino model space?

Or is it maybe a bug in the method, since I can bake Grasshopper hatch using other bake components without any issues?

image
image2117×707 122 KB

Example.gh (15.9 KB)

3

I hit the same problem, using Doc.Objects.AddHatch(h, attrib);

This seams to be a bug.

As a temporary workaround you can check and replace the pattern:

if (h.PatternIndex < 0 || h.PatternIndex >= Doc.HatchPatterns.Count)

                {

                    RhinoApp.WriteLine($"Hatch:Ungültiges Pattern (Index={h.PatternIndex}) auf Layer {lay.FullPath} ! Wird durch Solid ersetzt.");

                    int idx = Doc.HatchPatterns.FindName("Solid").Index;

                    if (idx < 0){

                        RhinoApp.WriteLine($"Hatch:Ersatzt durch Solid fehlgeschlagen! ");

                        AddRuntimeMessage(GH_RuntimeMessageLevel.Error, "Hatch:Ersatzt durch Solid fehlgeschlagen!");

                        return;

                    }

                    h.PatternIndex = idx;

                }