Creating accent edges on surfaces

[blakejohnson]

Hi everyone,

In the project I am working on, I have a couple different areas where I would like to add an accent edge on a surface with the edge gradually blending to flat. So far, I have been using the crease command in the sculpt environment, but the results have been unpredictable and generally not great. 

I'm hoping someone can help me figure out how to better control the shape of the T-spline edges and surfaces so I can smooth them out a it better. Below is a screenshot with some contour lines sketched over to help describe what I'm trying to accomplish. I want a a hard accent edge at the top of this protruding shape with smooth transitions around the bottom and back of the protrusion.

Below is where I'm running into problems. Toward the ends of the creased edges, there is always a weird star point that causes bad wrinkles. It seems like if I could smooth out the lines as I've drawn in blue, it would all come together much better, but I can't figure out how to do that... It actually took me a lot of work just to get it this close, but there are still those little curls at the end of the crease causing problems.

Any ideas or suggestions would be great! Let me know if more screenshots or explanation is needed.

[TrippyLighting]

Can you share your model ?

The topology of your T-Spline generally looks like it needs some improvements.

[PhilProcarioJr]

@blakejohnson

In addition to what @TrippyLighting said, as a general rule of thumb I split the mesh where I want seams instead of using the crease tool. Keep in mind though if you use that method make sure you stitch the split back together once it is a surface model.

[blakejohnson]

@TrippyLighting

Sorry, I'm still pretty new to Fusion and the forums. What is the best way to share my model? I don't want to share the whole project, so I've isolated just the T-Spline body in question in it's own file ready to go. I know I can share a public link or export as a STEP file or other types, but neither of those would let you look into my T-Spline situation, right? So what is the best way to share the actual Fusion file?

@PhilProcarioJr

Thanks for the suggestion! and interesting workflow. If I split the mesh apart to get those edges, is there a good way to make sure other areas where I don't want edges are still perfectly tangent or curvature continuous?

Thanks for you patience and help.

[PhilProcarioJr]

@blakejohnson

"So what is the best way to share the actual Fusion file?"

Export your T-Spline only model as a .f3d and post here.

"If I split the mesh apart to get those edges, is there a good way to make sure other areas where I don't want edges are still perfectly tangent or curvature continuous?"

Can you show me an example of what your after so I can see what your after?

By their nature the rest of your T-Spline body should remain curvature continuous that's why I'm asking.

[blakejohnson]

@PhilProcarioJr

Thanks for the quick tutorial on exporting. File attached - just a goofy side project I'm using to learn Fusion, but still, don't want to reveal the whole thing until it's done.

To answer your question, what I'm after is just one accent edge that blends smoothly into continuous curvature surfaces. So in the below screenshot, I want an edge roughly along where I've drawn the red line. Then where all the blue lines are drawn would need to be continuous curvature or tangent surfaces. I've actually gotten it pretty close, the ends of the edge just aren't really cooperating.

Perhaps I'm misunderstanding your original suggestion to split the mesh - I imagine that meaning that I should create a hole in my main body and then create a separate surface to fill that hole. Maybe a somewhat square surface where two sides are the edge that I want to be sharp, then the other two sides would need to be curvature continuous with the rest of the body (so two separate T-Spline bodies to build this shape). Or would you only separate the mesh along the red line and keep everything else connected so it's still technically one T-Spline body? 

One note on the attached file: you'll see that the shape I'm talking about is mirrored to the other side. There is also another instance on the from of this body where I am trying to create a similar accent edge effect - I'm having some issues with that one as well as the ends of the edge are curling up and creating a wrinkle where I would prefer them to just fade out smoothly. 

Sorry for all the questions. If you know of a good, video or written tutorial out there that goes deep into T-Spline surfacing, I'm fully willing to dig into that - I just haven't found that yet. I've watched many of the videos available through the Autodesk learning center, but they all feel pretty short and disjointed, I haven't really found anything that goes deep into a continuous workflow for a complex form using the sculpt tool...

Thanks again for all your help. 

[PhilProcarioJr]

@blakejohnson

T-spline training I have found is very basic and full of misinformation. Personally I don't recommend anything I have seen to others because of this. Instead I tell everyone interested to watch everything they can on SUB-D modeling and use a polygon modeling app to back up Fusions T-Spline tools. Although just about anything can be made with the current tool set they are very inefficient. One thing I noticed on your mesh is it is denser then it needs to be thus causing lumpy areas on the surface. Another thing is work in quads as much as possible. In my personal opinion ALWAYS work in quads.  

[blakejohnson]

@PhilProcarioJr

Thanks for the input. I'm sorry, what do you mean by work in quads? 

[PhilProcarioJr]

@blakejohnson

[PhilProcarioJr]

@blakejohnson

"what do you mean by work in quads? "

Make sure each face has 4 sides.

[blakejohnson]

@PhilProcarioJr

Thanks a lot for the video! Watching you tweak the topography and controls helped a lot. As soon as I saw you get rid of the star point at the end of the crease, a lightbulb clicked on for me. I'm still not sure I'm getting my topography exactly right, but as far as this topic goes, I think the accent edge discussion is resolved with the key lessons being: generally try to use fewer lines to reduce complexity of the sculpted body and don't end creased edges at star or T points.

[PhilProcarioJr]

@blakejohnson

"generally try to use fewer lines to reduce complexity of the sculpted body and don't end creased edges at star or T points."

As a general rule of thumb yes, always keep it as simple as possible. If you don't need more resolution don't add edge loops. There are a few cases where this is not true but that's a whole different discussion.