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This sub-panel appears in the Editing Context panel group which is accessed using F9 or clicking button in the Buttons window. This sub-panel is part of the Modifier parent panel. For further information about the common panel components see the Interface section on modifiers.

[edit] SubSurf

• Catmull-Clark/Simple Subdiv - Type of subsurfacing algorithm used.
• Levels: - Define the display resolution or levels, of subdivision surfaces.
• Optimal Draw - Changes the way Subsurf meshes are drawn visually.
• Render Level: - Define the display resolution or levels, of subdivision surfaces during rendering.
• Subsurf UV - -.

The Subsurf Modifier has the exact same functions as on the edit buttons. The only exception is that the Optimal Draw Button no longer serves the function of applying the subsurf effect to the position of the vertices, edges and faces. This function is now handled by the Cage Mode button. Now, the Optimal Draw button removes the extra wireframe lines which display as a result of having additional geometry. This button is especially useful to clarify and speed up the display of densely subdivided meshes.

There is much more to using Sub Surfaces and for further information see the chapter on SubSurfaces.

[edit] Example

Start

In this simple example we are going to make a Boomerang starting with a Mesh Plane object. The goal is to show you the potential of using the Sub-Surface technique to create models; in addition, cover some of the modifier's features.

We begin by creating a Plane object by accessing the Add menu from the Toolbox pop-up menu via the SPACE and chosing the Plane object; see (Start).

Plane

Next apply the SubSurf modifier to the Plane object. Then switch "Viewport Shading" to Wireframe using the (Z). By switching Shading modes to Wireframe we don't have to worry about hidden vertices while using the Border Select tool.

In addition, lets increase the "Levels" from "1" to "2" to get a better interactive rendering of what we are working on.

First group

Now we are ready to Extrude Edges to form the Boomerang. First Unselect all vertices (A) and then highlight the vertices shown in (First group), labeled "S". Extrude them (Only Edges) and Grab (G) and drag them to the right about 2 units along the X-axis (X), labeled "E1". Then Extrude them again and drag them 4 units along the X-axis, labeled "E2".

Second group

We form the other half by "mimicking" the other side which means doing the equivalent along the Y-axis, as shown in (Second group). First start at "S" and use the Extrude, Grab and (Y) combination to drag vertices along the Y-axis about 2 units, labeled "E1". Then Extrude and Grab again and drag these 4 units along the Y-axis, labeled "E2".

By now you can problably see the Boomerang forming and we are just about done. We just want to scale the tips a little, pull in the elbow and finally extrude (The Region) up the Z-axis to give it some volume.

Scale and push

Begin by narrowing the tips by selecting just the vertices at one tip and Scaling (S) them down a little bit and doing the same with the other tip's vertices, see (Scale and push).

Now we push in the elbow a little by selecting the "inside" vertices using the Box Select tool and Grab and move them in the direction indicated in (Scale and push) labeled "Push". The vertices to select are highlighted in Yellow.

The last thing to do is add some volume. We do this by Extruding the Region up along the Z-axis.

Select all the vertices (A) and switch to the left (NumPad 1) or front (NumPad 3) view such that we can see "edge on". Extrude the "Region" up along the Z-axis as shown in (Region extrude).

Region extrude

Don't extrude to far because we want a thin Boomerang.

Now we are done. We have a Boomerang that we can texture and render. (Boomerang) is the Boomerang in shaded solid mode.

Boomerang