UV mapping is slight shorthand referring to UVW mapping, UVW corresponding to the planes in 3D space, also commonly known as X, Y and Z. During this process a 2D image of a 3D model mapping the coordinates of each vertex, edge and face of the model. Inherently faces have a normal vector governing which way it faces and thus governing the nature of its edges and vertices. Having all of this information “baked” into the UV map allows textures and shaders to be applied to the model. This is the primary objective of a UV map.
Texturing and Shaders
Texturing a model applies an image to the faces of the model. Textures allow the artist to visually style the model and make each component appear as if it were made out of the material it is designed to replicate. Thus in example, a character’s jeans appearing as though they were denim rather than some amorphous smooth cloth. The texture image is created by overlaying a exported UV map over a digital canvas, giving the artist guidelines to what parts of the image will be applied to what parts of the model when the final texture is imported back into the 3D modelling software and applied to the model.
Shaders build further on textures by simulating material qualities, be it the reflective qualities of a metallic surface or the matte nature of most plastics. Shaders add an additional level of detail and complexity allowing the model to appear more realistic, reflecting more or less light, rough or smooth surface and many other modifications depending on the parameters of the shader.
The process of rigging a model involves applying a framework to the model allowing it to be manipulated for the purposes of animation. Rather than having to manually remodel each movement of the character, a rig allows it to be manipulated and repositioned more efficiently. The more comprehensive the rig is the greater the freedom of movement applied to the model. When creating the rig components who’s movement is governed by the movement of other components can be linked together in a hierarchy. For instance when a model moves its arm it’s hand is also moved, however it is possible for the hand to move without the arm moving, thus the arm would be the parent object and the hand the child. Utilising these relationships rigs increase the efficiency of animation vastly, whilst still preserving the integrity and anatomy of the model in the process.
There are several effective methods of animating a model or scene. Keyframes being the “old fashioned” although more accurately “old faithful”. Keyframe animation is a process of animating wherein key movements of the model are manually created and software is then used to interpolate all of the positions of the model in the interlaying frames. The strength of keyframe animation is that it gives the animator more control over the motion of the model at the cost of time.
Alternately motion capture can produce large quantities of animated footage in less time but as it utilises actors the quality of captured motion is limited by the acting skills and physical limitation of said actors. Motion capture involves an actor wearing a suit where key points of the body and their location in 3D space are captured in motion and that data is then fed to the model translating the captured motion to the model. Although cost effective both financially and time wise, not all motion capture is flawless and may require post capture editing and inherently has the aforementioned limitations of using actors.
Scripted animation works by assigning properties to a model thus allowing its properties to be governed by coding. Primarily utilised in games for animating the behaviours of NPC’s and the interactions of objects with the physics of the environment. Scripted animation is an extension of keyframe animation.