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Intersecting single plane roofs - Surface texture problem

Anonymous
Not applicable
Hello,

I am trying to connect single plane roofs together, as I need to create a roof with an odd geometry (refer to attached img). I have used SEO to connect 3 out of 4 planes, but the corners of the 4th don't seem to match the ones (refer to attached img). I know that its a weird geometry but it should be a way around it.

Btw, any ideas why my texture surface is looking odd when I perform the addition option under the SEO palette? The top surface material is be Paving-Asphalt Dark and the bottom and side should be Paving-Asphalt Light.

Thank you in advance.

Roof connections.jpg
8 REPLIES 8
David Maudlin
Rockstar
Panos M:

Rather than using SEO, I would try intersecting the Single-plane Roofs as described here: Intersect Single-plane Roofs. This is part of the AC18 guide, but this works for previous versions.

David
David Maudlin / Architect
www.davidmaudlin.com
Digital Architecture
AC27 USA • iMac 27" 4.0GHz Quad-core i7 OSX11 | 24 gb ram • MacBook Pro M3 Pro | 36 gb ram OSX14
Anonymous
Not applicable
Hello David,

thanks for your reply and advice. I have tried the way the you've suggested. My only problem is that the side of each single-plane roof that I want to be connected, overlap with each other. I cannot figure out how to ctrl+click the side of one roof, while simultaneously having selected the other. When I try it seems to select again the same plain and a window pops out with the title 'Roof elevations'.

This is not a problem at the example shown on the Graphisoft's web, as the ridges that need to be connected do not overlap with each other and when connected create a straight line and not an angle, as I am trying to do. I have tried to move an edge of one roof apart so that I could see the other and tried to use the suggested method, but ended up again with a weird finish at the corner (as the dimensions of one roof were changed).
Karl Ottenstein
Moderator
Panos, In situations like you describe, it is sometimes easier to use the polygon offset pet palette option to pull one of the roof edges away from the other to eliminate the overlap first.
One of the forum moderators
AC 28 USA and earlier   •   macOS Sonoma 14.7.1, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB
David Maudlin
Rockstar
Panos M:

In addition to Karl's advise about moving the Roof edges for easier intersecting: be sure you are clicking an edge (mercedes cursor), not a node or point (check mark cursor), clicking a node will bring up the Roof Elevations dialog box. Also, in your screen shot of the roof plan I do not see the Roof Pivot Lines, they can be shown with the Show/Hide Roof Pivot Lines command. In your case, it may be best to place the Roof Pivot Lines at the outside Roof edges so you know that the 4 Roof edges are at the same elevation and the slope is perpendicular to the Roof edge.

David
David Maudlin / Architect
www.davidmaudlin.com
Digital Architecture
AC27 USA • iMac 27" 4.0GHz Quad-core i7 OSX11 | 24 gb ram • MacBook Pro M3 Pro | 36 gb ram OSX14
Anonymous
Not applicable
Thank you both for your replies.

Karl, I have tried to use the offset pet palette options before, but I've ended up with a stranger roof connection, as the dimensions of the roofs are changed and thus wont connect properly. I have mention it below (Sat Sep 06, 2014 8:14 pm), but haven't named the function (offset) as I'm having another problem where I cannot see the name of each option of the pet palette when I hover my mouse (only a very small rectangle). I have posted a different topic with the title : ' Pet palette does not show the description of each action' . I would appreciate if you can give me your insight.

David, thank you for all your further advice. Please correct me if I am wrong, but the roof pivot lines are visible on the screenshot. It's just that the slope of the roof is towards the courtyard. I have tried your suggestion, that of drawing the roof pivot lines at the outside roof edges. I've only had to enter a negative degrees to achieve the desired slope result. But the only thing that I've succeeded on doing by this was to switch the uneven roof connections to the inside, rather than the outside.

Still cannot find a way to connect them properly with the way that you have suggested previously (Sat Sep 06, 2014 2:42 pm). Any ideas of what I might be doing wrong or should do differently?
David Maudlin
Rockstar
Panos wrote:
David, thank you for all your further advice. Please correct me if I am wrong, but the roof pivot lines are visible on the screenshot. It's just that the slope of the roof is towards the courtyard. I have tried your suggestion, that of drawing the roof pivot lines at the outside roof edges. I've only had to enter a negative degrees to achieve the desired slope result. But the only thing that I've succeeded on doing by this was to switch the uneven roof connections to the inside, rather than the outside.

Still cannot find a way to connect them properly with the way that you have suggested previously (Sat Sep 06, 2014 2:42 pm). Any ideas of what I might be doing wrong or should do differently?
Yes, I see them now: so they are set so the interior edges are all at the same height, which is fine.

Looking at your original screen shot, the roof planes have different dimensions from interior edge to exterior edge. If they also have the same slope, then the exterior edges will be at different heights. To adjust the slope of the problematic roof you can try this:
1. Select the Roof you don't want to change (will remain as is), place the cursor on the corner exterior node (checkmark cursor), and Ctrl-click (Windows) or Cmd-click (MacOS), the Roof Elevations dialog box will appear, select one of the Bottom elevation heights and copy this dimension. Cancel the dialog box.
2. Select the Roof you want to change, and again place the cursor on the corner exterior node (checkmark cursor), and Ctrl-click (Windows) or Cmd-click (MacOS), the Roof Elevations dialog box will appear, select the same Bottom elevation height and paste the dimension. OK the dialog box.

This will alter the slope of the Roof so its corner node is the same height as the other Roof. Again, try the Intersect Roofs method to get the correct valley between the two roofs.

David
David Maudlin / Architect
www.davidmaudlin.com
Digital Architecture
AC27 USA • iMac 27" 4.0GHz Quad-core i7 OSX11 | 24 gb ram • MacBook Pro M3 Pro | 36 gb ram OSX14
Laszlo Nagy
Community Admin
Community Admin
Here is an image in which I tried to explain why this scenario is hard (as you change Roof Slope, vertical thickness of Roof changes, plus you want to have the top of the Roof at certain height at its eaves and ridges, but you can only control the elevation of the bottom of the Roof via its Pivot Line).
If you look at the Section you will see that it is relatively easy to calculate the Roof Pivot Line Height and Roof Slope from the values of the desired Eaves Height, desired Ridge Height and perpendicular distance between the Eave and Ridge on the Floor Plan.

After you do this you will still need to set the Roof Edges to the proper angles, but that is a smaller task compared to this.

Edit: actually you don't need to go to the Section each time as I wrote in the image because you can measure the perpendicular distance between the Eave and Ridge on the Floor Plan as well.
FindingRoofSlope.png
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sinceV6
Advocate
Hi.
As Laszlo said... It will be really hard to do it using roofs, as they only have a single constant slope perpendicular to the pivot line, so if the opposite end (to the pivot line) is not parallel, each end corner will have different heights. Try that with four different roofs (with different odd connection angles in plan view) and you've gotten yourself a roof nightmare.

I am assuming that the geometry you are trying to make is kind of deformed; I mean, not constant in the way the roofs and its pivot line work. In attachment, in the two right side examples, end roof lines and pivot lines are parallel, and even with strange angles between roof's pivot lines, there's a way to adjust slope for each and keep every end line in the same Z position as long as that rule is met. Try to make them with the red outline and there will be problems.

This is a great opportunity and ideal scenario to use the shell tool. It'll be super easy to do what you want with four ruled shells (or even a single one could do). You'll loose some info from the roof tool regarding slopes, but it'll be really easy to model.

Or... as a last resource, use two meshes. First model roof top surface, then copy that mesh and lower it to use as SEO operator.

Hope I did not misunderstood and that helps a bit.

Best regards.
parallel_lines.png