Dashed Lines feature discussion


#1

So there was this new feature for SU2019. Dashed Lines. What do you think about it and its implementation?

FYI this is the SketchUp help page on the subject: https://help.sketchup.com/en/sketchup/applying-dashed-lines-layers#imported-dashes

I have mixed thoughts on this. The main reason why I thought it would help me is because imported plans from DXF would look more like its original than previously.

Having tried it now in a production environment (away from beta), I found that there was a serious issue with the approach of using Layers as the way to implement dashed lines. Other CAD software applies Dashed lines to the line entities themselves - not to layers. This means that when importing a DXF/DWG drawing for example, it doesn’t faithfully reproduce where lines are dashed and where it is solid. This is a shame I think - a missed opportunity. When SketchUp works better with other programs, I have a happier relationship with it, as do my external consultants with me.

On the plus side, keeping Dashed Lines in the Layers system keeps things a little neater, and I think it makes a lot of sense if one is working within just the SketchUp program and not sharing with others.

I wonder what other people’s experiences are with Dashed Lines so far?


#2

On a purely theoretical level, I think the implementation of dashed edges lines actually stays close SketchUp’s core philosophy of being a simple collection of edges and faces, isolated by grouping (including components), with visual changes implemented either through materials or styles than if a dash pattern were a property of the edge itself.

Edges are the geometry, lines are how we perceive them.

That being said, there were other ways of doing it that would also hold true to the core philosophy, by extending attributes of edges to include color, thickness (visible only - no effect on underlying geometry), and dash pattern (with a solid line being simply the default).

The one place that would have been an incredible PITA would have been in Styles, since each scene can only have one Style.

And I meant it when I said “on a purely theoretical level” since I haven’t upgraded to 2019 yet! I’ve got my license email, but haven’t installed 2019 Classic yet as I want a good block of time to do so - this weekend will see me actually trying it!


#3

I guess I have two problems with this. The first is the golden rule is layers are there to control visibility only! Whoops oh now they are for linetypes. There are no dished lines in the world and should not be as a part of the model. Dashed lines are drafting and that’s where they belong. I have no problem with having a method to display some dashed lines in SU. (We already had ways to do that.) I just don’t think they need to be part of the model objects and I certainly don’t think it should be by layer. I mean if you want only some edges of an object to be dashed are you going to have part of that object on one layer and other parts on another layer? Or maybe I just understand it yet.

Maybe the way sketchup remembers what is hidden in a scene it can remember which edges to display with a linetypes. And even this seems like it would live as a style override not a layer attribute.

What skalp is doing with background foreground seems to be a better option. However the last time I used it there seemed to be a real performance hit.


#4

I think good thoughts all round on this. I’m not sure I have much to add.

Starting to draw geometry in a layer is something that has been a cardinal sin in SketchUp for some time, and it looks like this is what we will be doing to make best use of Dashed Lines. So there will be a learning curve I guess for orthodox people like me.

Let’s all see how we make use of it over the next months and come back to the question. I imagine good practice will start to emerge.


#5

If all else fails we can go to extensions (dashed line ones, there are a couple) that were previously created and see how these work for us.


#6

I’ll just quote what I said in the main release thread:

Personally I see the implementation as something of a disaster due to how it encourages people to mix layers in the same drawing context. Playing badly with DWGs doesn’t make it better :frowning: . I would have from the start wanted edge styles to be controlled just as materials, with an inspector where you can create them, name them to give them meaning and apply them in a paint-like fashion to edges, groups and components. After all an edge stipple really is just a 1D texture.


#7

I think there is still the possibility for dashed lines to be applied like materials in future according to your logic. There’s no good reason for a layer NOT to have dashed line properties, just as it can have material properties.

So no need to change the dashed lines implementation as it is today to accommodate a future addition of dashed lines applied to edges directly. You may get what you hope for without breaking what we have now.

In that sense, I don’t think it is a “disaster”. Consider this a stepping stone!


#8

Yup, I’m hoping the current line style by layer will be a secondary way to use line styles, like color by layer is a secondary way to color objects. While the current implementation certenly isn’t ideal, it has luckily not shut the door for implementing it in more ways.


#9

I think i would have preferred this to be a group ‘entity’. Just like you assign groups and components to a layer, you would assign a Dash to a group.


#10

The main problem lies in the fact that a face cannot exist in SketchUp without the edges it is built of.
You can group edges seperated from faces but not vice versa.

As @Ccaponigro mentioned, keep the modeling in SketchUp, and the way you represent the model in LayOut.


#11

I feel the dashed lines are more dashed effect. By that I mean you can not snap to the individual dashes, the dashed lines are not really broken. In a CAD program these lines would be broken within a group type as you would draw them by hand. Obviously we do not want them broken as this would massively increase the line count entities. This is not a criticism for the current Sketchup 2019.

I will be interested to give this feature a go I am sure I will find a use for it in its current form.

Currently I use Profile builder assembly and I have a library of dashed lines I regally use which makes my use of dashed lines totally customizable.


#12

I am new to the argument about layers, and having all geometry in layer0, so it’s quite likely my thoughts about it are naive! But I’ll say them anyway…

Just about every other program I use has layers, and I do make use of them, they are a handy way to organize things. If I understand it right, people don’t use layers for holding geometry because geometry doesn’t know about layers, and adding connected geometry in another layer will affect the geometry in other layers, even if that layer is hidden at the time. Any new geometry added to the geometry in the non-active layer gets added to the active layer, which does lead to an amusing state where you could have the edges of an object in one layer and the faces in another.

So, because all of that can be a bit confusing, the general advice is to have all geometry in layer0, and only use other layers for non-geometry things. Is that just dimensions, or what are those other things?

Getting back to dashes as a layer style, perhaps there could be an option where any layer that has a dashed style is also automatically in a group. Like, one parent group for each layer. Really, just making any layer also be a group would let you have the advantages of organizing things in a handy way, without each layer interfering with each other.

There will be someone on earth who is currently depending on the fact that adding new geometry in an extra layer should also mess up the other layers, but if a new feature that isolated layers help most people, but gave those few people something new to think about, that wouldn’t be too bad.

I’m definitely not an architect, but this is my mental picture of how I might use dashes, which currently would have the geometry issues.


#13

It’s bad to draw in a layer other than Layer0 for the reasons you mention. So we should all be applying layers to Groups and Components only. These don’t have the problem of sticking together. We only mean faces and edges as “geometry” in this context.


#14

Phew it’s all getting a bit crazy…

For edges, we have :

  • Hidden, visible, softened. - applied to one edge or per component
  • Profiles - applied to whole model
  • Jitter, extension, endpoints, depth cue - applied to the whole model.
  • Colour by edge material - style affects whole model but applied per edge
  • Colour by layer - affects whole model (including surfaces!)
  • Dashed line Style by layer - affects the entire layer
  • Construction Guide - (non-exporting)
  • Back edges

And that’s before we get to Layout.

I agree with Eneroth that applying the dashed style to an edge should have been done in the same was as we apply a material.
(I also find the “materials by Layer” style similarly odd…isnt that what fill materials are for?)


#15

For the record smooth and soften are not component properties, but selecting a component and change the Soften Edges slider is just a shortcut for doing it on all edges contained in that component.


#16

eneroth, you can still leave geometry on layer 0 group lines together and put the group on a dashed line layer


#17

I know, but I don’t want to change the line style of groups as wholes. I want to have different line styles for different liens in an imported cad drawing. Also i don’t want to clutter my layer list with layers that I don’t use for visibility control.


#18

A few thoughts on dashing:

  • In 35-odd years of drafting, I’ve never used dashed lines to outline something. Dashed lines are always “standalone” entities, such as property lines, pipes/wires/ducts, or outlines of things above or below the view range (NOT the thing itself).
  • I was taught to always draw raw geometry (edges & faces) in Layer0, then group it (or make a component) and put the resulting G or C on a layer to control its visibility. Any other way leads to madness, since all layers associated with a piece of geometry need to be on for it to show up. Only Layer0 should be “always on.”
  • I already use layers for conceptual things like piping or CAD plans. Using them for dashing too would exponentially add to the number of layers I need to deal with, since (for instance) I might need 5 or 6 dashing styles in one plan (e.g. hot water, cold water, reclaimed water, waste & vent).
  • Even with the best dashing in the world, I still need to be able to use letter symbols on some lines (e.g. MA for medical air, O2 for oxygen, PL for property line etc.). Without this, no “dashing” solution is complete.
    I have been begging the SU team since Basecamp 2010 to give us control over line styling, including dashing, thickness, and end cap / joint style (round, square, miter). Until we get this level of control, either in SketchUp or in Layout, I will continue to need a separate app to post-process my SketchUp designs into decent PDF output.

#19

I think this expresses what I’ve been struggling to say about the layers/line style conceptual mismatch.


#20

@eneroth3 however, but i would still want the option of linestyle by layer as it is how i was taught to use linestyles in other cad software, and i would want to reflect it that way from import, my agenda is always more common ability from one software to another but i surely have less of an understanding as you, i think i will go back and read your thread about line styles and stipples again before i open my own can of worms