--- title: "Single-sided Meshes" url: "https://help.maxon.net/zbr/en-us/Content/html/user-guide/3d-modeling/modeling-basics/creating-meshes/zmodeler/single-sided-meshes/single-sided-meshes.html" section_path: "User Guide > 3D Modeling > Modeling Basics > Creating Meshes > ZModeler > Single-sided Meshes" description: "Two major additions have been made to ZModeler in ZBrush 2021: Edge Extrude for creating single-sided meshes and re-topology. And Inset Equidistant for …" --- # Single-sided Meshes *Making single-sided meshes a snap* Two major additions have been made to ZModeler in ZBrush 2021: Edge Extrude for creating single-sided meshes and re-topology. And Inset Equidistant for creating insets that don’t change your existing topology profile. --- ## Edge >>Extrude ![Single-sided mesh example](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_01.png)\ *Building a single-sided mesh with Edge Extrude* 1. Select or append the PolyMesh3D star. 2. Set the Tool >> Initialize X, Y and Z sliders to 1 and press the QGrid button. This creates a single polygon from which you can start building whatever you want. 3. Turn on Tool >> Display Properties >> Double to see both sides of your model. 4. Select the ZModeler brush, position the cursor over an edge and press the spacebar. Select “Extrude” from the Edge Actions. For an explanation of the options, see the Edge Extrude Modifiers section. 5. Click and drag the edge to extrude. Use Dynamic Subdivision to see your model in a subdivided preview. Add thickness if you want by activating the Thickness slider. When extruding the edge of a single polygon, tap Alt to change to extruding the Edgeloop and hold Alt to extrude the Polyloop. --- ## Re-Topology The new ZModeler Edge Extrude option can be used for re-topology. ### Getting started. 1. Select or append the PolyMesh3D star. 2. Set the Tool >> Initialize X, Y and Z sliders to 1 and press the QGrid button. This creates a single polygon. 3. Use the Gizmo3D to position the polygon on the surface of the SubTool where you want to start. Turn on transparency to better see what you are doing. 4. Press the Gizmo3D: Mesh To Axis to center the polygon. 5. If you want to use Symmetry, use Tool >> Geometry >> Modify Topology >> Mirror And Weld to divide the polygon in two. 6. Select the ZModeler brush. Position the cursor over an edge and press the spacebar. Select Extrude and make sure the Snap To Surface option is selected. Taper Sides can also be useful. 7. Create your topology. ![ReTopo](https://help.maxon.net/zbr/en-us/Content/Resources/Images/ReTopo.png)\ *An example of creating new topology using Edge Extrude\ ZBrush artist: Daisuke Narukawa* --- ## Extrude >> Modifiers ### Extend Surrounding Faces When an unselected face edge is extruded the surrounding face edges will be extruded as well. ### Regular Extrude The selected edge is extruded. ### Free Angle ![Extrude free](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_free.png)\ *Free angle* The extrusion can be any angle to the polygon of the starting edge. Holding the Shift key can be used to snap in 5 degree increments. While drawing out the new extruded edge, tapping the Shift key will swap between all three angle options. (Free Angle, Planar Angle and Perpendicular) ### Planar Angle ![Extrude planar](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_planar.png)\ *Planar Angle* Continues the extrusion on the same plane of the polygon of the starting edge. While drawing out the new extruded edge, tapping the Shift key will swap between all three angle options. (Free Angle, Planar Angle and Perpendicular) ### Perpendicular Angle ![Extrude perpendicular](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_perpendicular.png)\ *Perpendicular Angle* The extrusion is perpendicular to the polygon of the starting edge. While drawing out the new extruded edge, tapping the Shift key will swap between all three angle options. (Free Angle, Planar Angle and Perpendicular) ### Free Sides ![Extrude Free Sides](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_Free_Sides.png)\ *Free Sides* The sides of the newly extruded polygon can be an angle determined by cursor movement. ### Extend Sides ![Extrude Extend Sides](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_Extend_Sides.png)\ *Extend Sides* Extends the perpendicular edges of the extruded edge along the same angle of the edges from the original polygon. ### Parallel Sides ![Extrude Parallel](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_Parallel.png)\ *Parallel Sides* The sides of the newly extruded polygon are parallel ### Taper Sides ![Extrude Taper](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Extrude_Taper.png)\ *Taper Sides* The sides of the newly extruded polygon can be tapered by cursor movement up/down ### Single Row The extrusion is a single polygon of any length ### Num Rows The extrusion is divided by the number set in the slider. The polygons lengths will be determined by the extrusion. When this is enabled the CTRL key + moving your cursor back/forth can be used to interactively adjust the rows. ### Row Size The polygons are the length set in the slider and will be repeated as necessary along the extrusion ### Free Move The extrusion is free in space. ### Snap To Surface The extrusion will snap to the surface of underlying subtools. ### Smart Attraction Will actively try to merge with existing points. ### Normal Attraction Will try to merge points with existing points but only within a threshold that is determined by the average edge length. ### No Attraction Will not try to merge points with existing points, unless they are extremely close. **Expert Tip!** NOTE: A small shake of mouse or pen will force no attraction for extrusion until the mouse or pen is released. ### Force Symmetrical This postprocess will ensure that edge points extruded from symmetrical edges will themselves be symmetrical. It will also do its best to connect points on the symmetrical plane when needed. ### Don’t Force Symmetrical Symmetry is only considered for finding input edges. The actual extrusion algorithm will not apply any specific process to make the resulting points symmetrical. --- ## Edge >> Extrude Move Edge Actions >> Extrude Move extrudes the edge by duplicating it. It is basically a simpler version of Edge Extrude. It has the following modifiers, which are identical to Extrude Edge: Single Row/Num Rows/Row Size; Free Move/Snap To Surface; Smart Attraction/Normal Attraction/No Attraction; Force Symmetrical/Don’t Force Symmetrical. --- ## Edge >> Inset >> Equidistant ![Inset](https://help.maxon.net/zbr/en-us/Content/Resources/Images/Inset.png)\ *On the left, the result of Inset >> Equidistant.\ On the right is Inset:Standard, showing the change in profile.* While standard Inset works as in previous versions and tends to distort the mesh, Inset Equidistant will maintain the shape profile and smoothness of the mesh. ## Inset >> Modifiers ### Center And Border Will create a separate polygroup for the border and center. ### Border Only The inset will be the border and the center will be deleted. ### Center Only The inset will be the center and the border will be deleted. ### Inset Region The selected polygons will be inset as a whole. Giving equidistant insets along all of the faces. ### Inset Each Poly Each polygon in the selected area will be inset separately ### Equidistant The inset will be created equidistant all around the area, without changing the topology profile. Extra edges may be added to achieve this but the Custom Equidistant Snap (see below) can be used to limit the newly created edges where applicable. ### Standard The inset may change the profile but no extra quads/triangles are added. ### Legacy The inset doesn’t change the profile but will not necessarily be equidistant. Extra quads/triangles may be created. ### No Size Limit The inset can be any size ### Default Size Limit The inset will stop at the default size ### Custom Size Limit The inset will stop at the size set in the slider ### Default Equidistant Snap ZBrush will keep existing geometry and will intersect it around the edges to inset equidistantly at the standard distance. ZBrush will also precisely handle the intersection of inset segments. An additional point is added in the faces intersecting the median planes of vertices along the contour to be inset.\ This is an equidistant snap threshold of any new intersecting points that can be snapped together and will work in most cases. This option will only work when Equidistant is enabled. ### Custom Equidistant Snap ZBrush will keep existing geometry and will intersect it around the edges to inset equidistantly at the desired distance. ZBrush will also precisely handle the intersection of inset segments. An additional point is added in the faces intersecting the median planes of vertices along the contour to be inset.\ If the default threshold is creating more edges than desired, this slider gives a user-defined value for snapping. A higher value will limit the number additional edges that may need to be added to create an equidistant inset. This option will only work when Equidistant is enabled. --- ## Point >> Move >> Snap to Surface A new Point Action Move mode Modifier has been added – Snap to Surface. When moved close enough, the point will snap to the surface of underlying subtools.\ In Move mode, points can be snapped together to form triangles. --- ## Polygon >> Camera Perpendicular A new Polygon Action has been added that will set the camera perpendicular to a given face. ## Camera Perpendicular >> Modifiers ### Recenter View ZBrush will adjust the camera to face the clicked face and it will also recenter the camera to the center of clicked face. ### Do Note Recenter View ZBrush will rotate the camera so that it is facing the clicked face. The face’s center will be used as the rotation pivot, keeping the face center in place. --- ## Alt selection in ZModeler - - Alt+click or Alt+drag on any “unselected” face allows selection of one face or several faces. - Alt+click or Alt+drag on any “selected” face will deselect one face or several faces. - Alt+double-click on a “selected” face will allow to deselect all faces. **Important!** Note: When deselecting faces, ZBrush will try as much as possible to retrieve the original PolyGroup from before the face was selected. However, this may not always be accurate. --- ## Working with Subdivisions Any ZModeler functions that do not change the mesh topology will now work on a model with subdivisons. So, for example, masking polyloops is now possible using a single click.