Previously, we covered the second step in production stage of the 3D animation pipeline: 3D modeling. The next step would be 3D texturing. Before being delivered to the texture artists, 3D models are usually in a default flat gray color. To add colors, designs and textures to 3D models, 2D images must be laid out on them. The entirety of a 3D model’s color and surface attributes is often the result of this process.
To do this, various software packages and/or techniques can be used. Hand-painting the textures or even using real photographs to create a detailed or realistic appearance are among the options by which a texture artist can add texture to a model.
In this article we’re going to take a look at the texturing process as a part of production stage.
What is texturing in 3d animation?
Objects created in the 3D modeling component of the 3D pipeline are usually in a program’s default flat gray color. 3D texturing is in fact the art of clothing the 3D models with 2D images. Texture artists are responsible for applying color and surface attributes to the 3D objects. The general objective is to make the model’s surface match its concept art design or real-world counterpart.
For instance, if the model is supposed to represent a brick wall, the task of the texture artist would be making sure the 3D brick wall shares the same color and surface properties of a real-world brick wall when rendered. The same example can be made with a wooden table or a shiny glass window.
Generally, 3D texturing is supposed to portray three main properties of every surface in a 3D environment:
Texture, to a huge extent, can give the viewer a sense of material about an object in a 3D world. 3D texturing’s primary objective is to show the viewers a sense of what the object is actually made of by looking at it.
In the real world, every object portrays unique properties when exposed to light; such as reflection, refraction, anisotropy and so on. The same properties must be applied to 3D objects of the same material in a 3D animated world.
If every single detail on the surface of a 3D object were to be created in the 3D modeling phase, processing the objects would be a real burden for both 3D software and of course the 3D artist. 3D texturing provides a solution for this problem: It allows us to create small details such as wrinkles, scars, cracks, bumps, etc. on the surface of the models without imposing much pressure on hardware or software. Different types of textures and texture mapping can be used to make a 3D model look more realistic in a 3D environment.
3D texturing workflow
Every animation studio or 3D artist can adopt a slightly different workflow to reach the same results. Here in Dream Farm Animation Studios, the 3D texturing workflow is usually as follows:
To start the 3D texturing process, you need to unwrap the model first; which basically means unfolding a 3D mesh. Texture artists will create a UV map for each 3D object as soon as they receive the final models from the 3D modeling department. UVs are in fact 2D representations of 3D models. UV mapping will help wrap a 2D image (texture) around a 3D object by directly relating it to vertices on a polygon. The resulting map will be directly used in the process of texturing and shading.
Besides exclusive applications, most 3D software packages such as Autodesk Maya provide a few tools or techniques to unwrap 3D models. Choosing the right tool to create UV maps is a matter of preference or compatibility.
Unwrapping a 3D model in the texturing component is most often a must; unless you want to use other options such as procedural textures. These are 2D or 3D textures created using a mathematical algorithm (procedure) rather than directly stored data.
Most unwrapping is done manually in Dream Farm Studios; especially for characters. Manual unwrapping methods might take a little bit longer, but make the painting process much easier. Automatic methods are also available and can be useful for less important objects like background props.
2. Texture painting and shading
Correct display of an objects’ overall look and its interaction with light is a key step towards its believability and appeal. The wrong material or surface properties can end up being rejected by the viewer’s mind. This sums up the overall purpose of the texturing and shading process, going hand-in-hand. Texture is usually a 2D image and shading is a group of functions that determines the way light affects the 2D image.
The process of defining color information, surface details and visual properties of a 3D model is called “texture mapping”. Texture maps most used by Dream Farm texture artists include Base Color map, Normal map, Height amp, Diffuse map, Specular map, Roughness map and Self-Illumination map. There are tons of other texture maps as well, including: Ambient occlusion map, Displacement map Specularity/reflection map, Roughness/glossiness map, Metalness map, Refraction map, etc.
3. Lighting & Rendering
In short, the process of calculating the different maps assigned to the object’s shader and also the lights, is called rendering. Generally speaking, texturing, 3d lighting and rendering processes relatively rely on each other. So it is important to choose your texture maps based on the preferences of the render engine you’ll be using at the end of the production stage.
3d texture mapping
As Wikipedia puts it: “Texture mapping is a method for defining high frequency detail, surface texture, or color information on a computer-generated graphic or 3D model. The original technique was pioneered by Edwin Catmull in 1974.”
Final 3D models are usually in a default flat gray color. Adding colors or surface and material properties to a 3D model requires another step forward in the 3D animation pipeline: 3D texturing. There are generally 3 main properties we intend to display in a 3D model by texturing: material, light effects and some surface details.
3D Texturing is basically wrapping a 2D image around a 3D object and defining how light would affect it. Various software packages have different tools and techniques for adding texture to a 3D model. The texturing stage of the 3D animation pipeline includes unwrapping, texture painting & shading, and rendering. Textured models will be used in the rendering phase of the 3D animation.