What is Baking?

In the common language, baking is cooking something on a heated surface.

In the CGI industry, we use this image in order to talk about the process of transferring information from a model into another, resulting in a texture map, by saving the information of the mesh into a texture file.

Thus, Baking is very useful for many reasons, if you have made procedural texturing on your software (Maya, Substance, Mari...), you can simply bake your work in order to register this information into maps: this could be a color map or a displacement map, for instance.

All of these maps transferred from a high poly to a low poly exploitable mesh will add all the details to the low poly, from the displace to the cavities.

Also, baking is used in the movie & game industry for transferring high poly texture to its low poly version, as baking is transferrable. So your baking system will compare your two meshes in order to create a file that can be used to retrieve the high-poly details into the low-poly through a displacement or normal, for instance.

Hence baking allows you to save working time as it is obviously faster to work in a clean scene with an optimized low-poly mesh for both your texturing/lookdev or rigging/animation than working on a high-poly scan mesh!

What one has to remember is that baking has generally two main processes that can be complementary in your process:

• Single mesh baking: "Captures" the rendered appearance on your mesh to generate information.

• Two-mesh baking: compute information from a source mesh and transfers the result onto a target mesh. In this case, you already have the maps of your source mesh (from the single-mesh process), now you can transfer them to the second mesh.

The baking actually approximates the information onto a surface of a mesh to convert it into a 2D map. To do so, it generally uses ray tracing that will compute differences between the points positions of your model and the ones on either an offset cage or its high-poly version. That's how high poly points will find their positions in the low poly surface, converted into a map.

• Sometimes only a few channels of your maps can be used to create specific maps, such as Displacement or normal. All of these channels can also be consolidated as a single image, which can be very useful to economize the number of maps (like our tileable micro skin maps).

• For instance, Normal baking will give you a specific RGB map allowing you to order how the light will seem to appear on your model.

• In your favorite material painting software, you can save your work with the software integrated baking system. Usually, this type of software can also use the pre-existent information of the geometry and its form in order to enhance these textures, such as the curvature or cavity. About processing on where the edges or the occlusions are, your texture will be more efficient and will have better controls. In this case, too, your software will also bake 3D information into 2D map information

• Some software and tools will store an internal 2D map, allowing you to modify and refine the bake in real-time, before confirming and registering it once you're done with (Ex: Marmoset). Some others even allow the user to control their own skew and offset for matchless precision! 

• Texture baking also allows you to hide your seams on an unwrap UV mesh.

How does it work?

There are two main steps to the baking process:

1. Wrapping the mesh: You have a scanned head with millions of quads and a perfect topologized low-poly mesh. We will use the scanned head as a target mesh, and your base mesh as the source mesh that will be wrapped around the scan. In our process, you will have your Vface mesh and your base mesh. The point of the source mesh shares the same coordinates as the target mesh and allow us to bake the textures

The importance of edge extend

In most software you'll be confronted with many options for your baking, the most essential being the edge extend.

Indeed, when you are transferring your Uvs, the software will take into account the UV shells only with anti-aliasing to avoid gutters and missing pixels at the edge of the shells.

The edge extends (or edge padding) is used to spread the edge out of the UV shells for more security. It will give you the insurance to have no seams in your render!

In the different software sections, we will lead you to the edge extend option as it has a different name for each software. If this is not indicated, this means the software sets an automatic edge-extend by default.

How to use it for my VFace asset?

• Our XYZ asset is made for extreme flexibility: You can use our head and its textures as a source or as a target mesh, using its topology, UV maps, or simply the texture maps. You can also take advantage of the groom curves for your mesh, and even resculpt it and modify it at your ease!

• Moreover, if you already have a base mesh that you want to transfer our maps onto, this documentation is made for you! You will learn how to transfer the XYZ topology around yours and how to exploit the maps, using your favorite software, without any quality loss!

What's interesting for us and our VFace asset is the two-mesh baking, as you want to transfer our XYZ texture to your new mesh.

Currently, there's plenty of software that are using their own baking technology, but the process is generally the same. You work on your textures with projection techniques, then once you are done, you can bake the projection information into 2D maps. Thus, you will need to know how to bake your textures maps if you want to have full control of your project and your character's aspect.

In the next articles, we will see how to use your VFace Asset maps in order to obtain the best result for your meshes!

Now you know a little bit about wrap and baking, let's see the next steps and the checklist you have to fill before the process!