Normal map is a god-like existence in ZBrush. Many friends are very interested in normal map. The introductions in many videos and books have avoided many practical and key issues. This is really a headache. This article is a conceptual explanation of the experience of sculpting normal maps in ZBrush, and I hope it will be helpful to the guys.
What is a normal map?
Normal mapping is a special texture that can be applied to the surface of a 3D model, unlike previous textures that can only be used on 2D surfaces. As an extension of the bump texture, it includes the height value of each pixel, contains many detailed surface information, and can create many special three-dimensional shapes on ordinary objects. However, these three-dimensional shapes are made by using light and the The point normal angle is expressed, which means that if the normals of all points on a texture are recorded, it is not difficult to use this information to realize the false bump effect in the later stage.
The carrier that records these normals is called a normal map. But why is it called a texture? We know that a normal is a three-dimensional vector, and a three-dimensional vector is composed of three components, X, Y, and Z. So people came up with a clever way to use these three components as red, green, and red. The values of the three blue colors are stored, so that a new texture can be generated. This is the origin of the normal texture.
What are the scope of applications?
The normal map is mostly used in the rendering of CG animation and the production of game screens. The model with high details is baked out of the normal map through mapping, and then pasted on the normal map channel of the low-end model, so that the surface has a light and shadow distribution The rendering effect can greatly reduce the number of faces and calculation content required to represent the object, so as to optimize the rendering effect of animation and games.
Normal map is a technology that has received more attention recently, and it will become a major mainstream technology in the CG field in the future, that is, the next-generation technology known as the game industry.
Normal map is an important method to display more details of a 3D model. It calculates the details of the model surface due to light. This is a 2-dimensional effect, so it does not change the shape of the model, but it calculates the great extra details within the contour line. In the case of limited processing power, this is very useful for real-time game engines, and it is also a very effective solution when your rendering animation is time limited.
More specifically, for example, the special effects of Activision Blizzard's masterpiece "Call of Duty 6: Modern Warfare 2" use normal maps. After turning on this special effect, you can clearly see that there is an extra piece of transparent glass on the sniper scope of the sniper rifle, and the higher the quality of the normal map, the clearer and more vivid it is. On the contrary, turning off the normal map will not be able to see this layer of glass. This is a very important picture quality improvement relative to "Call of Duty 4: Modern Warfare". In future games that use Shader Model 3.0, normal maps will be added to improve the picture quality of the game.
