Every video game provides a kind of colorful presentation for the player (even in black and white). As most players experience memorable parts of the game, this is what a player hears and detects visually in the game. This detection can be about an image, some notes, or something known as texture.
Texture is a digital shell that covers objects in the game world. They can be unique or repetitive over a big area during the play in the different levels of the game. They can be interactive with the player or world, artistic, fantasy, or real and physical.
For example, sea mostly has a real texture of water. Some old engines just handle a simple image of water, whereas some modern engines (such as UE4) can provide the wave motion over the texture. Water is well known by everyone on our planet, and physical rules related to water have already been discovered by everyone during their lifetime.
On the other hand, Alien skin is something mostly related to art and fantasy of the game story. There is no experimental or proven physical aspect for such a thing. It can wave or vibrate with many different forms.
The art of creating materials in UE4 covers the physical and artistic features of design in detailed textures for the game.
Unreal Engine 4 defines a new method for creating materials. This method is based on the physical aspects of the real world. Things such as light reflections or heaviness will directly affect your model in the game world as visual elements and interactive behavior. You can make an ice cube that moves on the surface like a real one, or you can make waves of the ocean that have their own movements and reflect sunlight.
Basically, the quality of material has a direct connection to the graphics card and technologies involved in the CPU and the memory speed of the machine of a user. This leads developers and art directors to answer some important questions: how does our game render materials? Is it necessary that a user should have a super good machine to get what designers plan to show, or can we solve the quality aspect in simple ways?
A material can be created in three different ways. The first method uses an image that is copied to memory. This image gets loaded several times from the memory and depends on the size and alpha channel. It also gets some processing time from the CPU. The other method is to use the shaders technology. Here, the graphics card and the CPU are involved in creating a fully calculated shell on the surface of the object that represents the material. The final one is a mix of both. Unreal Engine 4 has all the tools to develop materials of high quality. At the same time, artists/developers can include some Shader-based effect on the surface of object. These features can be customized. This means that you can allow the players to set the graphics options of the game depending on the machine they use.
Let's go through an example of visual and interactive elements and how to create a physics-based material in the next section.