Exploring Materials

One of the key components that contributes to the immersive experience in Unreal Engine 5 is the sophisticated Material system. In this chapter, we will delve into the fundamentals of Materials and explore how they can be leveraged to bring your virtual worlds to life.

Mastering Materials is vital for achieving photorealism in your scene. Both light and Materials play a pivotal role and can single-handedly bring your scene to life. This is not surprising when you consider that, fundamentally, they are intertwined. In the real world, Materials serve as a means of perceiving light. As light rays interact with physical mediums, they undergo reflection, diffusion, and refraction, ultimately revealing the Materials they originate from. Therefore, viewing this chapter as an extension of the lighting topics would be apt since colors and the reflectivity of Materials will greatly influence the overall brightness and realism of your scene.Creating Materials should be...

Understanding Materials for Unreal Engine

In the realm of game development, Materials refer to the visual properties that are applied to objects within a virtual environment. These properties define how light interacts with the surface of an object, influencing its color, texture, reflectivity, and transparency.

Technical requirements

The project files for the chapter can be found at https://github.com/PacktPublishing/Architectural-Visualization-in-Unreal-Engine-5

The Unreal Material system may appear unfamiliar to those accustomed to offline renderers, but its immense flexibility and power become highly appreciated over time. Similar to node-based systems such as Cycles and V-Ray, Materials in Unreal are programmed in a simple yet advanced way that goes beyond traditional limitations, enabling the realization of any desired effect, whether it’s animated water, flowing lava, or shiny metals. Although further explanation will be provided later in this chapter, we’ll introduce two key concepts here: Master Materials and Material Instances.

Master Materials

In Unreal Engine, a Master Material serves as the foundation for creating various Material Instances: it consists of various nodes and functions connected in a visual scripting interface known as the Material Editor...

Discovering the Material Editor

Unreal Engine Materials determine the characteristics of objects in a scene, controlling their visual appearance. They provide instructions to the rendering engine on how surfaces interact with light, encompassing aspects such as color, reflectivity, texture, and transparency. These calculations rely on data from images, Material Expressions, and Material settings and happen “under the hood.”The place where everything takes place is the Material editor, so let’s start learning about it.

Material Editor interface

Creating shaders for your project in Unreal Editor does not require you to write any code – not directly at least. Instead, you can use the Material Editor, a visual scripting interface, to generate assets called Materials. These Materials are constructed by combining Material Expressions, which are nodes in a shader Graph. The results from these Material Expressions are then passed into the inputs of the Main...

Creating Materials properly

As we mentioned previously, everything happens inside the Material Graph. The Material Graph is constructed by creating nodes or Expressions and connecting them to the input pins on the Main Material Node. The data flows from left to right in the Graph, and the Main Material Node acts as the endpoint for every Material network since it contains the final input pins that determine the compiled information for the Material . Material Expressions in the Graph only affect the Material if they are part of a chain connected to the Main Material Node. By plugging Expressions such as constants, parameters, and textures into these inputs, you can define the surface properties of your Material and create a wide range of physical surfaces. Once you’ve done this, you have to understand what Expressions are and how to create them.

Defining Expressions

Material Expressions serve as the fundamental components for creating fully functional Materials within...

Optimizing your Materials

Let’s delve deeper into the concept of Material Instances, which we introduced earlier, and explore how they function. Additionally, we’ll explore another important concept called Material Functions. Both Material Functions and Instances contribute to optimization by enabling the reuse of Materials or their components, resulting in a streamlined and efficient workflow.

Material Instances and parameterization

Material Instances offer a convenient way to generate multiple variations of a parent Material without the need for recompilation. They are particularly useful when a group of related assets requires the same underlying Material but with different visual characteristics, such as furniture with various color options. Material instancing in Unreal Engine allows us to alter the Material’s appearance without costly recompilation, resulting in improved workflow efficiency and potential real-time changes during gameplay events, providing...

Summary

This chapter has been quite intense, covering a wide range of key concepts and topics. To avoid getting overwhelmed by this new information, it is crucial to put it into practice as soon as possible. My suggestion is to work with the scene you are currently using alongside this book and try doing the following:

• Create a clay Material by following the instructions provided in this chapter
• Generate a few Instances of the clay Material
• Assign these clay shaders to your scene
• Create your own Material Functions for UV mapping

In summary, we have learned about the ideal pipeline behind Unreal’s Material system, which involves utilizing Master Materials and Material Instances. We have gained an understanding of how to create a Master Material, what settings to consider, how to parameterize it, and how to create Material Instances from it.

We also discussed workflow optimization using Material Instances and explored how to create reusable Material...