For some models, creating bevels is a simple as adding a bevel modifer. But for other models, more complex methods are needed. One of these methods is creating transitions between two bevel widths. Be it a car dashboard or a piece of furniture, bevel transitions are everywhere. This short guide will show you the most optimal ways to create transitions between bevel widths.

Method #1 - Quick & Dirty

First, the quick and dirty method. If you’re in a pinch or if you’re modeling something that’s unlikely to be viewed close up, this is the method to use. This method involves using edge ceases to sharpen at variable levels. In this example, the sharp edge has a crease of 1.00 and the wider bevel has a crease of 0.00. To adjust the crease of an edge in Blender, use SHIFT-E.

Method #2 - Smooth Bevels

This method is a bit more complex and involves using the bevel tool (CTRL-B) to separately bevel each bevel width then combining the two bevels by cleaning up the merge point in step three. This method also using holding edges instead of edge creasing to have more control over the bevel profile.

Using this type of transition is perfect for important bevel transitions and high-poly modeling where model density is less restricted.

Method #3 - Sharp Bevels

This last method is for sharp chamfered bevels. Using creases and single segment bevels, it’s easy to create very clean transition points. The important step here is to merge the extra vertices in step four to restore the edge flow.

That concludes this brief intro to variable bevels! If this guide was useful to you, then please consider sharing it or contributing to the project’s Patreon page.

Let’s talk about Edge poles, those famously aggravating little points on a mesh that cause so many headaches for 3d artists around the world. Why are they so terrible? What can we do about them? And when are they actually good to use?

Edge poles are generally considered to vertices with more or less than 4 connecting vertices. On a polygon mesh, this means vertices with either 3 connecting edges or 5 or more connecting edges. Poles most commonly form when triangles or n-gons appearing in models, hence why such polygon types are generally avoided in 3d modeling. Triangulated meshes (such as game models, or photogrammetry models) are most notably known for consisting almost entirely of edge poles with very few 4-edge vertices, the same applies to meshes with large numbers of n-gons.

The Problem of Poles

So you might be wondering, why do edge poles get such a bad wrap? The primary reason is that an edge pole creates pinching around its perimeter when subdivisions or smoothing is applied. This is why a cylinder with a triangle cap looks so odd when applying subdivision surface smoothing. The example below shows why this can be a problem on curved surfaces. The cross-section view shows that the corner that contains a pole will yield an uneven surface when subdivisions are applied.

Despite the pinching created by poles, they are an important part of modeling and a necessary component for many modeling techniques and shapes. So this the rest of this post will attempt to explain a bit more about poles and how to use them effectively.

E-poles

E-poles are the most common pole type and consist of five edges intersecting at a single vertex. E-poles are most notorious for appearing when extruding faces on a mesh and for forming unwanted flat “corners” within the topology when edge loops meet or turn.  E-poles are also what form concave corners in hard surface models.

N-poles

N-poles are vertices that consist of three intersecting edges. This type of pole is far less common, but often appearing around poles or inset parts of a mesh. In organic modeling, this pole is often known as the “nose” pole, since N-poles are often necessary for modeling the base of the nose. N-poles are also what form the corner of a cube or most other convex corners.

Other Pole Types

Poles with six or more edges are generally considered to be bad practice and almost never show up in good topology. Again, on flat surfaces, 6+ edge poles can be acceptable if absolutely needed, but this is a rare case.

When are Poles Ok?

You’ve probably come to realize that poles are inevitable, and required for proper topology. But when exactly do we know when a pole should or shouldn’t be where it is? It all comes down to curvature. If a pole is changing the curvature of the surface, then it should be removed or eliminated. This usually happens on corners or any other areas of extreme curvature. Of flat surfaces, less visible areas, or areas with a slight curvature like a cheek of a face are areas where poles are least destructive and are where you should try to place or move poles to.

Moving Poles: The Great Compromise

One of the most requested topics I’ve received is how to move poles. And for good reason, poles can be very difficult to move without modifying topology in an adverse way. In almost every circumstance model density must be changed to accommodate a change in pole locations, causing the topology to quickly become very sloppy if multiple edges need to be moved. This is why the best advice for moving poles is to not move them wherever possible by planning your pole locations is advance. It’s pretty easy to judge where a pole will form by looking at the major flows of a surface and where they intersect. That intersection is where a pole will appear. Luckily, it’s up to you where that intersection happens.

But, in the case that you do end up with a pole that needs to be moved, there are a number of options for moving poles depending on your needs. Every situation requires a slightly different approach, however, there are some general techniques for 3 and 5-edge poles that can be a good basis for moving a pole. Something to remember, whenever a pole is moved, one edge loop must be removed in the direction the pole is being moved, while another is subtracted from wherever the pole came from. The reason for this is that the edge loops must be redirected around the new location of the pole. Otherwise, an n-gon will appear.

That’s all! I hope this short primer on edge poles has given you a better understanding of how to use them effectively. If this guide was useful to you, then please consider sharing it or contributing to the project’s Patreon page.

If you’ve ever tried to model a car or any other shiny object, you know how hard it is to get perfect reflections outside of using CAD programs. It’s tedious and virtually impossible to get 100% right.

With that in mind, I thought I’d talk about modeling specifically for these types of surfaces and the best ways to make it as painless as possible. Regularly used subdivision modeling methods rarely have the level of precision needed to make these kinds of surfaces, so I’ll be covering how “hack” sub-d modeling to best apply A-class surfacing ideals to the practical methods of subdivision modeling.ideals to the practical methods of subdivision modeling.

Evenly and Sparsely Place Loops

Even spacing, while often unavoidable without adding useless edge loops, is a goal worth pursuing. Even spacing ensures curvatures stay correct by not introducing any irregular areas that might produce artifacts.

Because of the way subdivision surfaces smooth and subdivide, even adding an extra edge loop that “seems” to follow the surface of your model can cause minute distortions to reflections if placed incorrectly. This is why it’s best to keep the mesh as minimal as possible, for as long as possible. Keeping the mesh simple so you can understand what your topology is doing.

Minimize High-Density Edge Poles

Edges poles are well known for creating mesh artifacts and distortions. But they are often unavoidable in certain areas without sacrificing another part of the model. That’s why it’s best to move poles to areas of less importance or curvature to make them less noticeable, rather than detrimentally removing them. Remove any unneeded poles if possible, but fall back to moving them if you can’t remove them.

A big request has been for a post covering moving poles, so I’ll hopefully be working on a full guide covering this soon.

Make Curvature Contradictions After Finalization

Curvature contradictions, meaning things like door handles on a car, or buttons on a control panel can cause major problems with topology and reflections. The main problem is that these contradictions can almost never be isolated without either large amounts of holding edges or creasing with very high mesh density.

To solve this problem, it’s best to add contradictions after one or two levels of subsurface smoothing have been applied. This way, the curvature is finalized before it can be altered negatively by any additional edits.

Don’t use Holding Edges when Possible

While holding edges are a great thing, they almost always cause distortion on some part of a model by adding edges along the entire length of the area the loop runs.  The alternative is to use creasing when possible.

Creasing, especially at high subdivision levels has almost the same effect as holding edges and can create topology that is much cleaner and easier to manipulate because it uses the extra subdivision of sub-surf.

Non-Destructive Sub-Surface

One benefit of non-destructive subdivision surfaces is that you can preview how the surfacing will look without finalizing it. This is an invaluable benefit of sub-d modeling that other modeling methods often lack.

Previewing how subdivisions will affect your topology is vital to making sure there are no distortions in your mesh. Because like I’ve said before, you never really know how it will be transformed by sub-d smoothing.

Use high contrast Materials during Modeling

One of the main difficulties in creating perfect reflections is previewing those reflections inside modeling apps. The default Matcaps built into 3d viewports are too low contrast to notice minute imperfections. That’s why using high contrast Matcaps or patterned reflection maps is a good idea for noticing things one normally wouldn’t.

Depending on your software of choice, you might have a Matcap viewer available or some other way to change the viewport material. If all else fails, a fallback is to render a preview of your mesh with a checkered map set as your environment texture.

That’s all! I hope this gave you some helpful tips for reducing mesh artifacts. But before I conclude, I want to thank CGcookie for graciously sponsoring this post. CGcookie has some fantastic modeling coursework that’s defiantly worth checking for both beginners and advanced artists.

So if you’re interested, check them out by clicking the banner below. :)