Need to create a viaduct structure - workflow procedure


I will be creating viaducts in my landscape model, I am currently still at the stage of inputting the model into sketch, but before I continue I would like some feedback that I am moving in the right direction that will enable me to create viaducts further down the line.

I am inputting the model based on a workflow suggestion - Make the whole 2D drawing completely flat? - #17 by gkernan

and combining this with the procedure Landscape & design tutorial.

SO I have my base map, on top of this is a ‘paper layer’ on which I am drawing the lines in the x-y plane. Then I am grouping objects to different landscape characteristics, whilst hopefully keeping lines and faces on layer 0., to enable me to turn on/off their visibility.

The idea is when I have entered all the model, I save it, then start using push/pull to add the height dimension

The model has a railway viaduct the palest grey diagonal on the right hand side, which will go over the mid grey Z sort of shape. Do I need to put lines through the viaduct to connect the underlying railway, - ?

Cheers KarenBasemap 3 - reset to this.skp (922.8 KB)

Don’t understand the question. Can you put it another way?

I am entering the model outline in the x y plane, Top down, parallel plane,

I have drawn the viaduct section (light grey) so that it creates a polygon, so that when I use the push pull it will get height.

as seen below

when I remove the viaduct section ( will now be green base colour of skecthup background) the rail track which will go under the viaduct is two separate polygons

But when I try to input two lines to join the rail track it doesn’t work, will have to send another message as can only load 2 pics


It worked when I connected the lines. I see that you’ve grouped everything which is good. You have to make sure that you’ve gone into that grey rail group and then draw the connecting lines.

Thank- you, glad I seem to be working in right direction, I do have another query though.

some of my groupings have

dark line and other don’t

The light pink towards the bottom does not have a bounding black line, whilst the lines in the green section RHS are thicker than those on the left, - any suggestions?

The thick lines are called ‘Profiles’ while the thin ones are called ‘Edges’. You can turn either of them off or on under ‘View/Edge Style’
For your drawing, the profiles usually show up as bounding edges or if lines do not touch, meaning no face was created. See gif below for example. You can see that I have both thick (profiles) and thin (edges) lines in my shape. I’ve also made a new shape and you can see that it’s outer edges are also thick as it’s a close face. When I move my smaller rectangle into the bigger one, the thicker profiles become thin as they are no longer ‘outer’ or bounding edges. Then I group the smaller rectangle and move into the larger one and you can see that the thicker outer profiles remain since grouping objects keeps them separate from one another. Lastly, there is one horizontal line inside the bigger shape that looks like it should be thin like the others but isn’t. It’s because if we zoom in and look close it does not touch the other side and therefor is not a closed face. Simply closing that little gap makes it thin and creates two new faces inside the larger one.

Hope that helps.

Thanks, I will have a look in the morning when my heads not so spaced, but thanks again for your help