3D scan mesh and point cloud issues: Cannot convert Objects.Geometry.Point to System.Double

Hi @jan-casas!

Could you send me a sample gh/rhino file to reproduce your issue on my side?

Not sure what could be going on right now, but I’d be happy to have a look and give you some pointers (or fix anything if needed! :wink: )

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Thanks for your quick response,
I’m having some trouble converting the mesh (fbx) to ghdata format. I attach a link to the fbx file.
Loading time 4mins aprox!
bug4AlanRynne.gh (19.9 KB)
bug4AlanRynne_withoutplugins.gh (16.3 KB)
Folder cloud: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.

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Hey @jan-casas :wave:,

I downloaded your file and opened it in Rhino. Can’t seem to see any colors/materials in the model.

that’s weird, i used the same file
Did you load the fbx file and display it in render mode?
I will check in a couple of hours :slight_smile:

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Yes, i checked the display more and it’s rendering material color. Int his case they don’t have any colors. Anyways, I’ll wait for your check.


When loaded in gh also, when deconstructing mesh should return vertex color

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Ok, looks like i am missing the texture image. I get this error while opening the model. But this also means that you only have a single material for the whole mesh. Which is one reason why it doesn’t return vertex colors. I don’t know much about this specific case. Maybe @AlanRynne or some other rhino expert can help.

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you are completely right, i updated the folder with the png image
I’m so sorry for the issue

I’m trying to figure it out, but I’m not sure what format the color input needs to receive. At the moment I only have a sparse point cloud with no color in the stream.


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Take a look at this thread to add color(renderMaterial) to GH geometry. I hope it helps.

Can you share the pointcloud file @jan-casas? Or rhino file with point cloud imported.

the point cloud is created from the vertices of the mesh.
I uploaded the 3dm, an xyz point cloud of the mesh and the gh file.
I load the ghdata (mesh) and initialize the workflow but the color doesn’t work :frowning:
Thank you

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Ok, then i’ll play with it. Getting color info from texture is tricky and I am not sure if its possible in gh. I’ll give it a go when I get a chance.

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the input asks for color, what format does it have to have? → could you give some examples
I mean, the color info is extracted correctly (list of int-rgb-values), it’s just a problem of format

Hi @jan-casas

Ok so the thing is, the Pointcloud that you can access from the Speckle Schema Node component is quite hidden because it’s not the most straightforward thing to setup.

I’ve attached a demo file for you to check out but, but in essence:

Points is not a list of point (counter intuitively) but a flat list of numbers representing the coordinates of said points in order: [x1,y1,z1,x2,y2,z2,...]

Colors are supposed to be unsigned ints, which grasshopper supports natively by just shoving the colors in an int param.

image
2023-01-27 16.47.48

PointCloud-Test.gh (11.2 KB)

And here’s the result:

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It works at full speed!!!
you made my day guys, thank you so much! :heart_eyes_cat::heart_eyes_cat:

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Can you share that stream with us?

I feel the urge to move around your point cloud for a while haha :rocket:

sure!
1% density: Speckle
20% density: Speckle
40% density → 8M points :heart_eyes_cat:: Speckle

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Wow,
that looks cool.
And the big one even runs on my M1 Mac Mini 16 GB flawless.

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I hope you don’t mind, we had a small party in your building :sweat_smile::heart:

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@mephisto maybe we should look into this. Maybe we could add voxel-based downsampling on the client side, so that there’s one repo and you could pull at different resolutions as needed?

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