Panel Loops

The Panel Loops feature, located in the Tool > Geometry sub-palette converts your existing model into a set of separate surfaces (panels) with thickness. These panels are defined by the different PolyGroups or visible polygons. Various set­tings alter the final result. This function is similar to the SubTool >> Extract command, except that it converts the existing model and offers a lot more control over the results. This new tool is perfect to quickly create complex groups from a model’s parts, ideal for hard surface sculpting. The Panel Loops function will only work on meshes with no subdivision levels. When Panel Loops are created, ZBrush will automatically assign a PolyGroup for each edge loop that is indicated by the Loops setting. These PolyGroups are assigned for the benefit of using the Polish by Feature slider. (See Other Additions)

Panel Loops by Daniel Bystedt

Panel Loops by Daniel Bystedt

Panel Loops Workflow

The workflow is quite easy and allows you to test various configurations for transform­ing your model:

1. On a model, define multiple PolyGroups. Each of these will later become a different surface with its own borders. A quick way is to paint a mask, then press­ing the CTRL+W hotkey (the shortcut for the Tool >> PolyGroups >> Group Mask Clear Mask function). For a quick demonstration, select the DemoSol­dier in the LightBox >> Tool menu. This model already has multiple PolyGroups. An alternative to masking is to hide all polygons that you do not wish to be part of the Panel Loops.

2. In the Tool >> Geometry >> EdgeLoop UI Group, locate the Panel Loops section. Within this you will find the Polish slider which has a small dot symbol in it. Click this dot to toggle it solid. Now click the Panel Loops button.

3. The model should now have been split into individual panels based on the Poly­Groups (or visible polygons). These panels have borders with thickness, and these have been bridged together as defined by the various settings in the Panel Loops sec­tion of the UI.

4. To really see this, go to the Tool >> PolyGroups sub-palette and click Auto Groups. Each part should now have its own PolyGroups. Hide some of the PolyGroups by Ctrl+Shift+clicking on the mesh or split each PolyGroup into a separate SubTool by using the Tool >> SubTools >> Split >> Group Split function. You will now be able to clearly see what the Panel Loops feature created.
Because Panel Loops create different PolyGroups, you can use the various AutoMasking settings like the Brush >> Auto Masking >> Mask by PolyGroups to work only on the first selected PolyGroup that the brush touches. Or use Topological auto masking when working on a panel so as to not affect the other groups.

Panel Loops in action

Panel Loops in action. The original model with its PolyGroups is shown at left. The results after using the Panel Loops function are on the right.

Working with the Full Model or with Visible Polygons

Panel Loops work in either of two different ways:

  • By creating multiple Panel Loops based on the PolyGroups of the current model.
  • By creating a single or multiple Panel Loops for the visible polygons of the cur­rent mesh. With this behavior, the mesh will be made fully visible again as soon as the Panel Loops are created. Any masks will also be inverted. This allows you to modify the Panel Loops without affecting any other parts of the model.

If Double mode (explained below) isn’t enabled, the new Panel Loops will be merged with the underlying surface rather than creating new parts.

Panel Loops Settings

Several settings found in the Tool >Geometry sub-palette (EdgeLoop section) provide con­trol over the Panel Loops feature. Those settings are explained below.

The Panel Loops settings

The Panel Loops settings

Loops

The Loops slider defines the number of polygon loops which will be created on the bridge between the inner and outer surfaces of the panels. The more complex your bevel shape is (see below), the more loops will be required in your panel edges. Bear in mind that each loop will increase the polygon count.

Double

This mode creates the panels with front and back surfaces. It is enabled by default. When Double is disabled, the panels are created as beveled sections on the original surface.

Append

With this enabled, ZBrush doesn’t delete the original PolyGroup when the Panel Loop is created. This mode is very similar to the Tool >> SubTool >> Extract function except that you have access to advanced bevel and polish options.

Appending Panel Loops

The Append option’s results. At the top, the original polygons in green. At the bottom, the resulting panels. The bevel curve is show on the right

The Append function is affected by the Double option. If Double is turned off, the created Panel Loop is composed of an outer surface and surrounding bevel but no in­ner surface. In other words, the panel will be a new surface only rather than a volume. Note: If you wish to convert the Panel Loop mesh to a new SubTool, use the Tool >> SubTool >> Split >> Split Unmasked Points feature.

Inner

This mode creates the Panel Loop inside the model rather than outside. The difference between Inner and a negative Elevation setting (see below) is in the direction of the beveled edge shape relative to the original surface.

Polish

The Polish slider applies a polish effect on the resulting mesh — especially to the border of the PolyGroups — to create clean edges. Polish has two different options and you can switch between them by clicking on the small dot at the top right of the slider.

  • With the dot open the polish will reduce the smoothing of the original surfaces but may create some overlapping polygons at the bevel location. These can eventually be smoothed with Polish by Feature. This option can produce sharp points where three or more PolyGroups intersect.
  • If the dot is closed ZBrush will round all PolyGoup borders.

Bevel

The Bevel slider defines the size of the bevel between the PolyGroups.

Bevel Profile

The Bevel Profile curve defines the shape of the bevel between the inside and out­side surfaces of the panel. The left of the curve represents where the bevel connects to the surface (outer por­tion of the mesh) while the right of the curve is the bevel’s outermost edge. (Inner portion of the mesh) The height of the curve then defines the shape along that length. If the curve does not reach past the middle point of the curve editor, you will have some empty space between any panels that are adjacent to each other. Once any dot is placed past the halfway point of the grid (the fourth square) the bevels will begin to overlap and ap­pear as if they are connected. 3.8 Elevation
The Elevation slider defines the height of the panel relative to the original surface, letting you specify whether the panels will be raised above the surface or be depressed below the surface. A negative value will create panels that depress from the original sur­face while a positive value will create panels that are raised above the original surface. Note: The Thickness value and the Bevel value (along with its profile curve) are related. Having a high value for one setting and a low value for the other can create unexpected results. If the thick­ness is very low, setting a very high bevel value may create overlapping polygons.

Thickness

This defines the thickness of the panel, as well as affecting the distance between the panels. The Profile Curve can also have an effect on the panel cap. If the curve is closer to the bottom of the graph, the cap between each panel will be enlarged.

Thickness value

How the Thickness value affects the distance between panels

Ignore Groups

If performing a Panel Loop while only a portion of the mesh is visible, this option al­lows you to keep the current PolyGroups. The advantage of this would be if you wanted to create additional panel pieces across an already created panel and not have ZBrush create panels for every PolyGroup.

 

Regroup Panels and Regroup Loops

For these options see Regroup Panels and Regroups Loops