Cineversity

I seem to recall seeing somewhere that you can control the normals of edges.  I have a complex shape.  I want to grab the outer edges and extrude downward.  Some of the edges extrude parallel and some extrude at a 90 degree angle.

I can reverse the normals 180° but I can’t seem to adjust them 90° so that all of them will extrude in the same direction.  Is this possible or am I dreaming?

The Align Normals command doesn’t seem to do anything.

And the Cloth nurb is extruding everything when I just want to extrude without a cap.

Thanks

TAK

Hey TAK,

The Normals that are in question, while “align” them are “Polygon Normals”. These are surface directions, normalized based on the points and their resulting influence of the polygon itself. If you import objects from other apps, you might find sometimes a Tag for more information, e.g. point normals. But that is not an option for manipulation in C4D.

Please provide a scene file with the polygon in question—or edge in question.

My tip for “orthographic extrusion”: Use the extrude options, but online to an nearly un-noticable amount, then pull the reminding selection-axis in the direction you need.

All the best

Sassi

Here is a quick file… it is just a piece of the model.  What I am trying to do is extrude the outer rim of the whole model in one fell swoop to give it a thickness.  You will notice that the extruded edges go in all different directions.  The Reverse Normals command does reverse the direction of the extrude.

Thanks

Hey TAK,

You need to work with the Coordinate Manager (not the one in the Attribute Manager.)

If you like to have a flat line, you need to know the level on which they should be. Position.Z=0.0 in your case perhaps. The following is not my idea way to work, but you ask for the fast method.

As I mentioned above, you use the “Extrude” only a tiny bit, e.g., Offset=0.1 or 0.01. Try first to use a large numbr e.g., 8 to see where they go, find an average Edge Angle ( -35º perhaps) to have them from a z view (right in your case) nearly equally extruded, then take that step back and use the first 0.1 or 0.01 extrude with that angle. Then set the Z size in that Coordinate Manager to zero and AFTER that, the P.Z position to 0.0 (always while the selection is still given!) Repeat this exactly one more. (Of course 0º Edge Angle)

Do another Extrude (offset larger now, I used 4.0 in the image below) and “size” and then position. You get a “coast line that follows of course the topology of the given model. The smaller the first two steps, the more precise the is the curve of the coast line.

One word to the Normals, the orientation of the Polygon Normals was OK, all share the same direction. The polygons itself have quite a variety of direction. Some would even undercut each other if just extruded in one step. I think I would have drawn a Spline Guide and created the Polygons manually. With no long thoughts about that. Extrude is nice and a great tool, but for some stuff, they are not build for. You could go even with the fast method above and use the resulting points of the new coastline to set the polygons. Just my two cents.

All the best

Sassi

Just for the record, I did it twice, just to see if it works and here is #2 with HyperNURBS on and rendered. A clean border.

Thanks doc.  I got it to work with a minor modification.  I did the two mini extrudes and then used the move tool to pull out the edges rather than a final extrude.  This way I now everything is exactly perpendicular.

I understand the process except for the -35° angle.  I actually went with -45 but can’t wrap my head around why I need to do this and how it then lines things up.

In the long run I got the model built properly.  Now comes the real hard part.  I need to bend the whole thing into a difficult shape.

I may be back with further questions.

Thanks again.

TAK

Hey TAK,

Nice that my method worked for you. :o) Thanks for the feedback.

The angle, if it -35º (or -45º) is not really the point, and nothing that would have perhaps any relevance for other situations. Let me explain. If you extrude the first time your specific edge, some of the parts just go into the Z and some in X direction—which was the initial problem. If you have an extrude that goes just vertically up and then use the coordinate system to set it back to 0 (in your case!) then some edges would not have moved, some would. In the moment you rotate the whole result, the parts that go vertical up (useless) point now more into the directions that you wanted originally. The ones that were on the right way without rotation, go back a little bit. Roughly this is exactly what makes the “useless” extrude and the parts that were “nice” more equal. One goes up a little and one goes down a little, and everything in between in your case. So—with that little initial trick, we get a more useable result. To get a stable result and keep the bevel on your model I suggested to minimal extrude twice. THEN extrude to the final extension/frame, what ever you will call it.

the mini amount made that step nearly invisible, but it works.

All the best
Sassi

Hi Sassi
I have lthe same problem bugging me. The extrude angles increase with every extrusion. Did I understand your answer to the problem is not to use the extrude command but build seperate geometry and connect it with, for instance, the brigde command to the base geometry with the extrusion ‘problem’?

Hey Geertjan,

I is always case depended, I hesitate to set things general, as each model might need a different treatment.

What I did here is to find a sweet spot where the maximum up angle and the maximum down angle are similar, then set the size of that to zero. Not 100% precise but works.

If the new edge from the extrusion is very similar to the original edge, then I would extrude only a tiny (very tiny) little bit, and pull the resulting edge then in place.

Yes, sometimes a target geometry might help. As you mentioned.

As I wrote, case dependent, which means, I would like to have a look into an example from you, and several of them, and check what makes the most sense then (So far I can tell, modeling is not based on “the one and only way to do things)

Let me know where I can help.

All the best

Sassi

Hi sassi.
Here is an example. I tried to recreate it in a new example project but couldn’t. I think my original project got so messed up that I should remodel it;-)
Anyway in this example you can observe the edge polygon getting wider and wider. The question is, apart from remodeling;-), how to stop it from getting wider and wider.

Hey Geertjan,

Here is an image of your file, let me know if you like to have the C4D file as well.

I went back to your “collar” and did a very small extrusion from it. Just to get a new edge. This edge, while active, was then easily pulled away from the original edge. If you need subdivision, you might introduce them via “Knife” or after selecting the edges with the Mesh>Create>“Edge Cut Tool” Disable N-Gons perhaps.

Let me know if you need more information about that or something else, I happy to share my thoughts.

All the best

Sassi

Hi Sassi
Thanx, a simple solution:-) You have put me on the right track again.

Hey Geertjan,

You’re welcome.

I have developed this technique to create the Kitchen Aid (Aida K.) In my movie short JET. Scaling (if needed) and moving (as well rotation) the resulting new edge allowed me to model very efficiently.

Good luck with your visualization!

Happy Easter

Sassi