Bridge Problems

Hello,

Due to another post, I have been looking more at some problems I see from "Bridge". I know there are other ways of construction for this example, but this is about the Bridge tool, not other ways of construction via other tools.

First of all, the simple example:-

I want to bridge between these 2 [merged] meshes across the highlighted edge_Loops.


Using the "Bridge" tool on those selected edges gives 2 initial problems.


For problem 1: That is due to the polygon normals of both meshes facing in the same direction. A more simple example will show that more clearly.

A simple plane, duplicated and translated over, the 2 planes then merged. 2 edges selected for Bridge.


Using Bridge causes the construction of a twisted quad.


Undo the Bridge, select one of the polygons, and "Flip Polygon Facing". (It does not matter at this time if "Flip Polygon Facing" results in the 2 polygon normals facing each other or facing away from each other.)


Using the Bridge on those same 2 edges will then produce a correct result.


Going back to the original example.
I select all the polygons that make up one of the meshes, and "Flip Polygon Facing"


Select the 2 edge_loops (as shown in pic 1) and using the "Bridge" does remove problem 1 (as shown in pic 2)


Problem 2, the polygons created spanning the object, that is not something I have found a way to correct with any of the tools (such as edge re-order).
I find a need to select partial edge_loops, such as shown here:-


Bridge those:-


Then select the remaining edge_loops, and bridge those.

I can fix the normal problem. But I won't fix the spanning problem. There is no perfect solution for this tool. It will always work on some cases but failed on others when the geometry is complicated. You can use the streamline 'Bridge-Multi' tool, D+RMB I think. It is more predictable and generally faster because you don't need to select.

You can use the streamline 'Bridge-Multi' tool, D+RMB I think. It is more predictable and generally faster because you don't need to select.

The "Edge_bridge multi" is for closing/bridging 2 mesh with equal number of open edges, it would not/will not work correctly for the example above.

In your case case, you can use single bridge to bridge the first and the last pair of the edges. Now you have a long gap. Ativate "Edge_Bridge_Multi", click one of the edge, move cursor over its oppsite edge and release hotkey. The long gap should be filled with new polygons.

Here is an old video
http://www.youtube.com/watch?v=16H0qlEOLgY

Thats another solution to the problem/limitation. Thanks.

Here is an old video

Not sure how that is related to current example. Is that correct link?

Not sure how that is related to current example. Is that correct link?

Because you wrote "The "Edge_bridge multi" is for closing/bridging 2 mesh with equal number of open edges". it is not true and the video shows how it works. It didn't go through all the open edges. Forgot to mention, you can hit a number key to close the tool so you can have the new geometry subdivided.

Because you wrote "The "Edge_bridge multi" is for closing/bridging 2 mesh with equal number of open edges". it is not true and the video shows how it works.

I still do not see how it is of any help to the problem posted.
What it does show me, is there are other calculations at work, to stop creation of a bridge across edges who`s vertex direction is not within a specific angular limit and may cause polygon overlaps/coincident polygons, or is it working from polygon normals?

Could you show me an example where that tool would make a usable bridge between 2 mesh of un-equal open edges?

ya i would also like to see some improvements with the bridge command too.

in maya, max, silo, modo, and blender i can make nice caps for even sided cylinders, by loop selecting the open edge, and deselect 2 edges that are parallel, than performing the bridge operation.

as you can see doing this from my maya install gives me a very nice all quads cap on the cylinder.



but doing the exact same thing in nvil, gives some pretty broken and useless results.


the fasted way i found to accomplish this in nvil was to manually drag out the bridges using the stream line tool.

the fasted way i found to accomplish this in nvil was to manually drag out the bridges using the stream line tool.

The quickest way to do that in NVIL, would be to have a single n-gon cap and use "make Quad"

even still would be nice of the bridge worked in that case like it does in every other app out there.

also quadcap on that ngon dosnt work for me, woudlnt i still need to delete some edge loops to to get the same result as showen in maya.

ah the quad cap command dosnt work, but the basic streamline one does it.

even still would be nice of the bridge worked in that case like it does in every other app out there.

I agree.

also quadcap on that ngon dosnt work for me, woudlnt i still need to delete some edge loops to to get the same result as showen in maya.

Not the "Quadcap, the "Make Quad" streamline tool. Sorry, I should of been more specific.

ya been away for a while and havent had time to work on 3d.

i really need to spend like a day, to play with all the new streamlines tools, and make some keys and radial menus to use them.

well maybe in a few weeks.

This can be a very complicated subject. I was having trouble with problems 2.
Now I seem to be having trouble with problem 1.

With problem 2, I selected part of the edge loop. And that works fine.
But I saw that some of the edges twisted, like problem 1.
So I selected all the faces on all the twisted edges. And Flip Polygon Faces.
That worked on all but one:

I thought maybe I'd missed one. So I selected that face, and Flip Polygon Faces.
But that didn't work either. I'm at a loss now.

Is there a way to show normals?

As for problem 1: I would expect that to happen, if the normals are facing the same direction and the faces are somehow in front of each other. When the faces are side by side and facing the same direction the bridge tool works fine in the simple example with only 2 faces. I haven't testet with a complex mesh.

But what I noticed with the bridge edge tool was that it connects the 2 top edges when the faces are in front of each other, but when I move one face sideways, so that the bridge polygon of the 2 top edges would form a rhomboid, nothing happens. No bridge.

The streamline bridge tool where you select the edges within the tool gets that done.
So there are different bridge tools that act differently. So I guess one would have to build a custom streamline tool to get this all incorporated into one "tool"/hotkey?

Hi 3dwizzard,

Is there a way to show normals?

No, not polygon normals (that I have found), but there are other options.

In the drop down main menu:> View > Object Shading.
There are options
1: Cull (to hide faces)
2: Back face in Grey (to change the color of the back_facing of polygons)



1: Cull
There are also icons on the top menu that can be used for the "Cull"
[I am using a simple cylinder for visual reference, I have removed the top polygons of the cylinder]
If you click the little down arrow on the icon, you will see 3 options.

The first icon, is "Cull BackFacing". That will remove(hide) all the back_faces of the polygons. So for the cylinder, you will only see its outside. [for a cylinder, all its polygon normals(by default) point outward]


The 2nd icon, is "Cull None". So you will see both front and back of the polygons.


The 3rd icon is "Cull Frontfacing". So now you will only see the back_faces of the polygons.


Personally, I do not use those options, as on complex models it can be a little disorientating / confusing on what you see. I prefer the next option of:-

2: Back Face in Grey.
What that does is to change the color of the back_faces of the polygons. You can set the color you see(for the back_faces) to any color you want. Just go to "Edit > Preference > colors" -> Object color > Back face color"


There is a little icon on the top menu that will toggle "Back Face in Grey"

With it disabled, both front and back faces are set the same color.


If you then enable "Back Face in Grey", the back_facing polygons change to the color set in the preference.


Hope that helps.

-Steve