Skalp Sections Inside Multiple Groups

Hi @Guy

I have this model with several sections in one scene. This is needed to create a floor plan of the whole building because the building spreads at several different heights but only has one floor.

I would like to know if it’s possible to have them hatched in one go.

Also, when I try hatching a single one of these sections, it creates the skalp section inside the group, but it is calculated for all elements in the model, even if they are outside of that specific where the section is inserted.

Is there a standard workflow to have collaborators of the model using skalp to hatch sections on their parts of the building and then import those hatched sections into a master file and have them all show in a specific scene of that master file.

First Skalp doesn’t support sections inside groups. Skalp section should always be in the model and not inside groups or components. There are a lot of technical reasons why this is done this way. This is a topic which we already looked into it a lot of times but where we always come to the same conclusion. Because components can be nested, have multiple instances where each instance can be scaled, rotated, … this can’t be done in a correct way with way how Skalp is implemented.

In SketchUp you can’t get this done. How I would do this is by cropping and stitching the different section together in LayOut.

I thick the best way is to create also sections in the master file to generate the overall sections and ignore the section in the submodels.

This isn’t a solution for my case as the master file has all rooms at different heights. If I section the bottom room the top room becomes wrong (the reverse is also true). If I section somewhere in the middle, both top and bottom rooms will be wrong.

I have tried exporting each room as a Xref component and reimport it after having made a Skalp section inside each of them. It should work as long as Skalp geometry get’s consolidated in each and I should be able to retrieve this geometry in the main file afterwards.

I guess Skalp layers would be invisible at first but I could turn them on in specific scenes and that could work. I’m still having trouble understanding how Skalp layers work though.

Do you have any advice that I could use?

Thanks for your help.

Can you explain what you mean with this?

It’s not designed to something like that. The only way to do this is combine the section on different heights in LayOut to one plan.

I understand that Skalps creates a Section in the model. It’s a live section and that live section has a layer associated to it. But I still didn’t understand how Skalp manages section groups that are attached to scenes. Those groups, were the ones I was expecting to save with the model and use in the master model.

The workflow would be as follows:

  1. In the MasterModel.skp I have a component with a section inside.
  2. I export it with “Save As” (Example: Room1);
  3. Edit that component in another sketchup instance (Open Room1.skp);
  4. Use Skalp to create that Room1 Plan’s section
  5. Save Room1.skp
  6. Reload Room1.skp in the MasterModel.skp
  7. Skalp geometry should carry over
  8. However I don’t know in which Layer it is.
  9. If I had this on a Layer I could activate that Layer in a specific Scene and use that geometry as a section group for this model along with the corresponding active sections that would also live in the MasterModel.skp

I hope I made this clearer… :thinking:

From SU2020, where it’s possible to hide nested groups in scenes. We don’t use anymore layers to manage our sections. Now the different sections are inside of the Skalp sectiongroup.

Also be aware, that when Skalp is active the visibility of the groups is fully automatic. If you turn on the visibility of a sectiongroup it will automatically be turned off again!

I see. I don’t usually use hide to do this, but it makes sense with Skalp so that you can control Layers amount.

I suppose there is a group naming convention which is based on the scene that is created when we create the section with Skalp.

If I create a scene where the groups I need are visible, then as long as I save hidden geometry scene property, even if Skalp hides the groups nby mistake, they should keep their visibility in that scene.

If not, I do have to be careful not to work with Skalp on those scenes. I use a working scene and several section scenes, so that might work.

A question that arises if I’m going to keep reloading these Components:

  • Is the geometry inside each section group regenerated each time Skalp changes a section;
  • Or do you delete it that section group and create a new group each time skap recalculates a Section?

This is very important as if I’m going to reload the model but the Skalp section group is retaining the same PID, I can use it without having to unhide it everytime I reload it.

I’m going to try this workflow. It might work.


The geometry is regenerated every time.

We try to keep the section group. But sometimes the empty group is deleted by SketchUp, in that case we recreate a new sectiongroup.

Skalp will manage also these group in none Skalp scenes to avoid that our sections are visible in scenes setup by the user.

It’s on our list to make ik possible to show Skalp sections in none Skalp scenes. I see wat I can do for you.

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I think that is a great option.

Maybe what we would also need is that we can choose if Skalp hides a specific group using Hidden Geometry or a Layer. By default Skalp would use the current method, which I agree it’s the best. But if a user would choose the hide by Layer (maybe an advanced hidden option) Skalp would assume that would be because the user would want to micromanage which scenes would have that layer will visible.

The Layer method is nice as an option, because hidding Skalp groups using Layers would allow the user to avoid the missing PID if the section group would be rebuilt from scratch, as this would affect hidden object’s visibility stored in scenes.

Until now I’ve been using SectionCutFace, manual hatching and drawing my details on top of it. This would allow me to have much simpler models and only detail sections. I liked how I could use a Single Section Cut Face in combination with a lot of different scenes to create several different representations of a section just by changing styles (I could make hide edges and leave profiles on to have only the section outline, I could hide hatches by removing textures from the style, I could use front face color and shade it diferently…). There’s a lot of flexibility in allowing the user to manage Sections per scene.

I was expecting to use Skalp the same way though with all it’s wonderful automatic feature set. I also expected that after a certain level of detail I would be able to turn off Skalp auto refresh geometry, and be able to draw on the section cut group myself for added detail like waterproofing membranes, bolts, window frame detailing, roofing and joints details, etc…

Of course I can still do that now, but I have to force it a bit, by copying geometry from a locked/hidden group, into a new group managed by me, where I could further detail the section into a construction drawing like this:

The above section is always from the same Section Cut Face and a very simple model that only features exterior and interior wall faces and no building layer like multilayered walls or slabs.

I’m still getting used to Skalp, and though I think I’ve bumped into some things that, at least for now I cannot do, I’m already a fan.

I will get some time, after finishing this project, to try to fully explain what I’m missing, hoping that it will give you some ideas for further development, as I think those would allow Skalp to be even more powerful and would allow most of us to avoid drafting in CAD altogether.

In a quick summary I think these would be:

  • Allow Layers for controlling section group visibility, as an advanced mode;
  • Allow us to break auto section refresh for a certain Section as an advanced option (this might be possible already, I have to investigate). With this option Skalp would allow us to draw on those sections without risk of refreshing the sections and loose our manual drawing;
  • Have an option that would allow for a manual forced refresh which of course would make Skalp recalculate that section and we would loose our manual editions;

Thank you for all your work with Skalp, it’s truly a great plugin!

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I have read your entire discussion with Guy and want to give some insight on how I would do what you’re trying to do. I believe Guy knows the solution I would use as that’s what it sounds like he’s already doing in layout in some way or another, the (some way or another is the hard part if one isn’t sure of some of the options). It’s quite easy I believe. If you need a reply soon as I believe I can fix what you’re trying to do with a workaround you can email me at and I can walk you through a virtual meeting on this, would also be nice to pick your brain a bit as I’m sure you could help me out as well. Anyways if you can wait I’ll reply to this thread when I can hopefully soon.

  • Tucker

Hi @ArayaCAD

First of all thanks for taking the time and having the patience to get involved.

I think I understand what @Guy is proposing in Layout but that is not a real option for me as Layout isn’t the only output I need. Most of the time I’m presenting the project to the contractor, engineers, landscape architects and clients with the main Sketchup 3d model. I then send 2D drawings of the model to them, after the online meetings.

What @Guy is proposing requires a cropped plan view of each room to be assembled in Layout and connected to the next room. As it is, this requires reassembling the plan based on puzzle pieces in Layout - each piece is a different plan view of a part of the model.

I rather do the same but within Sketchup in 3d.

What I’m doing is that I’m keeping an external model of each component that is at a different level and reload it.

The external model has a Skalp section at root level of the model and a component which is the same component that lives in the master model and that I’ve converted to Xref (I’m guessing you know about right-click “Save As” and “Reload” that you can perform to an in model component). I can edit this component either in the master or in the external model and then save it out and reload it in the other model. I can do that myself or with a collaborator.

I use the external model for two things:

  1. Higher detail on each of the 3 wings of the project and a simpler Layout for 1:50 to 1:5 scaled drawings, with faster reloads and workflow than if I’d need to reload the master model.
  2. Generating the skalp section, unlocking it, copying it’s geometry, pasting it’s geometry in a group inside the xref that is assigned to a shared layer active only on plan view.
  3. Saving that xref with the copied skalp info externally
  4. So It can be reloaded in the master model and have that plan view layer active on the right scenes.

This allows me this setup (rightclick and open it in new tab):

I hope you can understand the usefulness of this setup for both Layout simplification and effective collaboration within the office.

EDIT: I just seen that you sent a message. Will check it out.