Multiple faces driving me crazy!
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@wo3dan said:
It doesn't ever happen to my models.
So you're saying that you have never had a multiple face on any of your models?
You really need to buy a lottery ticket
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Yes, that's what I said.
@hellnbak said:
...You really need to buy a lottery ticket
I'd rather have that model of yours instead of the ticket.
For I also never win with lotteries.
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I get the double face on occasion as well. Don't have a clue why, as they seem to form randomly in areas where I have never edited, but seem to occur after I do an intersection to that surface.
BUT, I have discovered 2 ways to find them.
The first applies to surfaces that have some curve in them. It does not work with flat surfaces.
With all lines on the surface both soft and smooth, and hidden lines off, roll and rotate the surface and examine it carefully. You will see some individual faces seem to have a decidedly harder outline and seem somewhat flat. They are double faced. Just delete the "flat" face after you turn on hidden lines.In the 2nd method, I found that when I made some surfaces (flat or curved) in a semi-transparent material (both front and back faces, not just 1 face) I saw some individual faces had a slightly darker appearance. Those were the double faces.
So, if you suspect double faces, select the whole surface, paint both sides with some throw-away color. Edit that color to be semi-transparent (around 20-50%) and view the surface with with hidden lines off. Delete the darker faces after you turn on hidden lines. Then repaint with desired color. -
I would add to this, that another way to inspect for duplicate faces is to turn on xray mode and orbit to inspect faces. At least on my machine the doubled faces are a little less transparent than others.
You can also see internal unwanted closed faces when you visually compare the sharpness of edges seen through multiple layers of faces. Internal closed faces readily form when loops of edges are coplanar and aligned with global axis. -
@hellnbak: Do you by chance, have quick hands? That is, do you model quickly? This may be nothing, but maybe some double clicking or something?
My machine is borderline acceptable, and I am a slow modeler, but of course I do get these duplicate faces occasionally.
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I'll get it running the Make faces plugin from time to time. I've had instances where I'll get 15 or more faces on top of each other. You can tell when you go to texture it and nothing shows up. Usually running and intersect followed by Thom's cleanup will sort most of it out. It is very frustrating sometimes. Sketchup and profanity seem to go hand in hand in my house.
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Thanks for the suggestions, but finding the multiple faces is not a problem, I was just hoping that someone had a good tip on how to avoid creating the faces in the first place. Actually I wasn't very hopeful, but figured it was worth a shot. Like I said, I'll just have to live with it (just like all the other SU strange and annoying quirks
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Quirks or charm?
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Hmmmm.....I'll have to go with quirks, and I'm being kind. Maybe SNAFU would be closer. I know now why they made SU free - you can't demand a refund for something you didn't pay for
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@hellnbak said:
... I was just hoping that someone had a good tip on how to avoid creating the faces in the first place. Actually I wasn't very hopeful, but figured it was worth a shot. ......
I haven't seen any example model yet, showing this very issue. There's no guarantee whatsoever that I'll be able to come up with an answer but I wasn't joking in offering to seriously look into it.
Well, it's up to you. -
Sorry. My models are too large to attach to the forum, so I've attached just a hood from one. I do remember that it, like most other things I've worked on, enlarged my vocabulary as far as multiple faces when I was making it, adding faces and subdividing them. That's not to say that it will do the same for you, maybe you've got that one in a million copies of SU that is problem-free. If so, I'll buy your computer, price is no object
How 'bout just the hard drive?By the way, you didn't answer my question - have you really never encountered multiple faces in any of your models? Even just a double face?
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Here's a sample of mine. Draw lines on the faces in this model and you'll find that SketchUp starts adding extra faces where there already are faces.
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@thomthom said:
Here's a sample of mine. Draw lines on the faces in this model and you'll find that SketchUp starts adding extra faces where there already are faces.
Well, I drew lines all over it, subdivided it, kicked it, screamed at it and caressed it, and wouldn't you know it - not a single extra face
Actually that was one reason I was reluctant to upload a model, I figured that Murphy's law would guarantee that the problem wouldn't show itself when you wanted it to. -
@hellnbak said:
@thomthom said:
Here's a sample of mine. Draw lines on the faces in this model and you'll find that SketchUp starts adding extra faces where there already are faces.
Well, I drew lines all over it, subdivided it, kicked it, screamed at it and caressed it, and wouldn't you know it - not a single extra face
Actually that was one reason I was reluctant to upload a model, I figured that Murphy's law would guarantee that the problem wouldn't show itself when you wanted it to.Before drawing a line:
drag a selection rectangle right-to-left over one of the large faces. It should select two - the one you see and the one on the back.
Now draw some lines criss-crossing the large face, make the selection rectangle again over one of the faces, it now selects more than two faces.
Happens every time. -
Yup, that did it. I'm assuming this model is made up of just normal faces, so what does using the select tool first, and specifically right to left, have to do with it. And more importantly, is there maybe something in this that could help me with avoiding the double faces, something I may be doing that is causing them? I don't see what it could be, but I'm still a little hopeful.
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I did managed to get the extra faces as suggested - there are two extra pairs plus the original [3 'overlays'].
If occurs if I draw a diagonal on the large face with the tiny 'spike' at its base.Another interesting observation...
IF I draw the diagonal so that its end point is less in the Z and greater in the Y [than the start] I get NO extra faces... BUT if I draw the same diagonal on the face with its start and end points transposed, OR I make the other diagonal [in either direction] then there are extra faces added...Just weird...
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@hellnbak said:
Yup, that did it. I'm assuming this model is made up of just normal faces, so what does using the select tool first, and specifically right to left, have to do with it.
Just a method of counting the number of overlapping faces.
If one of the faces had a different material you'd see z-fighting. -
@thomthom said:
Here's a sample of mine. Draw lines on the faces in this model and you'll find that SketchUp starts adding extra faces where there already are faces.
Hi Thomas, I see the issue. And it's not difficult to see where it originates from. Bad geometry. Unfortunately you present a model with faces that aren't flat to begin with. There are latent two faces to begin with for each large side face, although SU cannot show the diagonal. Most likely because it's waywithin tolerance.
Concider one face, the one that looks like a rectangle.
Measuring differences perpenducular to the face with the 'Tape Measure' tool isn't helping much after self aligning axes (right click > Align Axes) to the face. Maybe SU gets confused because of whatever?
So align the axes manually and forget the 'Tape Measure' tool but...- ad a 10mm line on the face, perpendicular to the face.
- select the face and the 10mm line.
- select the 'Scale' tool and scale both face and 10mm line up by 100 and again by 100.
The result is a twisted face without a (hidden) diagonal. Apply 'Fix Problems' to see the change happening. The geometry was bad to begin with.
(I wonder if it has anything to do with having length snapping off. I have it on all the time although small)
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@wo3dan said:
....So align the axes manually......
By that I mean: use the base edge for red and the hinge edge for green.
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@wo3dan said:
(I wonder if it has anything to do with having length snapping off. I have it on all the time although small)
hmm... Maybe..?
I was wondering if it had something to do with minor deviances occurring when you transform entities.
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