Hi my name is Jonathan Williamson, you may visit me also at my website at: http://www.montagestudio.org

In this tutorial we will be taking a look at the retopology tools within Blender. The primary advantage to retopologizing a mesh is it allows you to easily create low-res models from high-res, sculpted models. The newly created low-res model can then be used to generate normal maps or displacement maps from the high-res model. This is particulalry useful in game developement. Let’s take a look!

Step 01 - Base model

First off we need a model to work from. I have chosen a head I modeled a while back. Most anything will do, but for best results use something fairly high-res.

File > Open > filename.blend

We’re now ready to really get started!

Step 02

In order to retopo our high-res mesh, we need a second mesh to work with. Press Spacebar > Add > Mesh > Cube. You should now be in Edit Mode (do you see vertices?), if you’re not hit Tab.

Delete all of the vertices by pressing X > Erase Vertices

Step 03

Go to the Editing buttons (F9) and press “Retopo”

Step 04

You may now begin extruding or retopologizing your new mesh by Control + LeftClicking along the base model to create the vertices. Keep in mind the edgeflow you’re creating, you need, and want to create something that’s friendly to animation, texturing, etc. If you’re not familiar with good edgeflow, try googling it, there are numerous resources and examples out there to help you.

Step 05

Using the same process here, you can see I’ve started to outline some of the major loops.

Note: you must be in shaded mode for retopo to work. Toggle between shaded and wireframe by hitting Z.

Step 06

The next step is to fill in the faces. Select four adjacent vertices at a time by Shift + RightClicking on them and then hitting F to create the face. Do this along all of your loops.

Step 07

Now it’s time to create the other primary loops for the face using the same techniques. Again
you can create new vertices by just Control + LeftClicking anywhere you’d like a vertex. This is a very quick, efficient way to create new loops. As you can see in the screenshot I’ve created several more loops to connect the mouth and nose loop to the eye loop.

Step 08

Following the steps above you can finish off rest of the head. Be sure to keep your loops clean and even as you can. Remember, this is a lowpoly model that we want to be able to normal map and animate in the future, thus small details are not our concern. Just so long as the mesh is clean.

Step 09

There is one last step we need to complete before calling the model finished. Let’s go ahead and mirror our mesh along the X-axis. Do this by going to the Editing buttons (you should already be there) and clicking on “Add Modifier” then “Mirror.” This will mirror your mesh along the X-axis and give you a complete head. You can hit “Apply” to make the mirrored mesh real.

Last Words

As you can see in the first image below I’ve moved the final model over so you can compare the two. They should be very similar in shape and structure. From here you can very easily create UV maps, textures, normal maps (as in the second image,) etc. Not only that, but now you know how to take your ultra-high-resolution sculpt and create a lowpoly very of it easily for animation or whatever else fits your fancy.

Good luck!

Jonathan Williamson

To learn more about Blender or download the open source application visit http://www.blender.org/

This entry was posted on Saturday, November 29th, 2008 at 11:39 am and is filed under All, Blender, Blender Modeling, Instructors, Jonathan Williamson, Modeling, Tutorials. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.