Making Interactive Elements Using Blueprints

The Blueprint system is the backbone of Unreal Engine 5 as it provides incredible flexibility and power. It enables designers to utilize advanced programming concepts and tools, making scenes interactive and offering precise control. Although you could technically use UE5 for architectural visualization without touching blueprints, doing so would mean missing out on the engine’s true potential. UE5 is not just a render engine; it’s a game engine with immense power and by neglecting blueprints, you’d underuse and waste time. Therefore, investing time in learning the Blueprint system is invaluable. We are going to explain what blueprints are, how they work, and the essential components for creation/modification. We’ll also present real-world use cases and guide you in building a functional blueprint class while covering key concepts and hands-on experience. Then, we’ll learn how to modify existing blueprints...

Technical requirements

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

An overview of blueprints

Premise

From a personal standpoint, as someone with a non-technical background in coding, I initially found blueprints to be quite challenging to grasp. Over time, however, I have acquired the skills to handle them. I can understand why someone might initially hesitate to learn something that seems so distant from traditional Archviz logic. Nevertheless, I believe it is crucial to learn, or at the very least understand, Blueprints due to their undeniable usefulness and power. Even if your primary interest lies in the artistic side, Blueprints offer something valuable. They are a language for communicating with Unreal Engine without writing code (although they are pieces of code). The beauty of blueprints lies in their simplicity as they consist of blocks that anyone can comprehend. They enable you to bring almost any idea you have to life. So, join me on this journey, and don’t worry if you feel overwhelmed at times – it’s perfectly...

Exploring different types of Blueprints

There are many types of blueprints, but they can be broadly categorized into two main types:

• Level Blueprints: A specialized type of Blueprint that acts as a level-wide global event graph and is automatically created for any level you add to your project.
• Blueprint Classes: These are the most common type of blueprint, and they can be used to create almost any type of gameplay element. For this reason, they are often shortened to simply “Blueprint.”

Let’s go through them in detail.

Level Blueprint

A level Blueprint is a special type of Blueprint that is used to control and automate many aspects of a level in Unreal Engine. Each level in your project has its own level Blueprint, which is created by default and can be edited within Unreal Editor.

To access it, you can do one of the following:

• Click on the little blueprint icon in the Level tab, which is next to each level.
• Click on the...

The Blueprint editor

The Blueprint Editor is similar to other panels in Unreal Engine, which is one more reason to become familiar with it quickly: many sections and concepts are the same across different tabs, such as the node system resembling the material node system. Also, while the logic may differ, concepts such as variables, events, and interfaces can be used in other parts of Unreal Engine. For Archviz, learning the basics is usually sufficient since complex game programming is not typically required. Let’s explore these basics together.

Overview

Take a look at the next figure to get a first glimpse of working with the blueprint editor:

Figure 10.12: Overview of the blueprint editor

Here’s a quick explanation of these parts:

1. Toolbar: This contains the most commonly used tools and commands
2. The Components tab: This is a super important tab as this is where you add components to your Blueprint. Components are the individual...

Blueprint essentials

As you’ve seen, blueprints are a very broad topic, and they can be used to create anything you need. I’m quite sure these concepts might be unfamiliar to you since they were to me at first. But don’t worry; over time, you will learn how to create and modify blueprints just by practicing.

For now, since blueprints cover a wide range of possibilities, it’s not easy to explain how to create blueprints in general. It’s much better to show you how to create specific blueprints instead. By learning a few practical examples, you’ll be able to apply similar approaches to your cases. But before doing so, we need to cover some final concepts.

Nodes

Blueprint objects are defined by using different types of nodes such as events, function calls, flow controls, and variables in their graphs. Each node type serves a specific purpose, but the process of adding and using them is generally the same. We have three main possibilities...

Project – creating an interactive lamp

Follow these steps:

1. Inside the Content Browser area, create a new folder named Blueprints. Right-click inside this folder (or use the aforementioned methods in the first section of this chapter to explore different types of blueprints/blueprint classes) to add a new blueprint class. Choose Actor as the class and name it BP_myFloorLamp. Double-click the blueprint to open it.
2. Click the plus (+) button in the top-left corner to add components. Type Static Mesh to add a static mesh component. In the static mesh details, choose a floor lamp mesh from your Content Browser area.
3. Next, add any other components you need, such as a cable or decorations, using static meshes as well. In the Viewport tab, transform these components (move, rotate, or scale) to achieve the desired appearance.
4. The order of components shown in the list to the left is important; the first element will be the root of our blueprint. You can leave it as...

Summary

In this chapter, we started by covering the basics of blueprints, a core element of Unreal Engine that allows us to program various functionalities in our scene. We covered the different types of blueprints available in Unreal, focusing on those most useful for Archviz. Then, we quickly learned how to create these blueprint types. Additionally, we covered the widget blueprint and how to create them (a notion that we will face again in the next chapter).

Moving on, we delved into studying the blueprint class editor and its various sections, understanding nodes, functions, and variables.

To apply our knowledge practically, we created a step-by-step blueprint actor for a floor lamp, introducing concepts that can be reused for other blueprints.

In the next chapter, we will continue with practical exercises, building upon the floor lamp we just made. We’ll explore level and widget blueprints, which will enable us to control the floor lamp’s on/off functionality...