Communicating between Blueprints

In the previous chapter, we embarked on a journey of discovery into the Blueprint system. We obtained an overview of its various aspects and even crafted our first Blueprint actor—an interactive floor lamp. Now, let’s take a step further and delve into more advanced examples. Our focus will be on exploring two topics introduced earlier (level and widget blueprints), which we’ll reinforce through practical exercises, as the theory has already been explained.

These powerful tools allow us to interact with actors and scenes during runtime, be it within gameplay or cinematic sequences. Before we dive into these topics, it’s crucial to grasp the fundamental knowledge of blueprint communication. We’ll explore concepts such as casting, interfaces, and Dispatchers—tools that enable blueprints to effectively “talk” with one another. So, let’s embrace these new challenges …ready for that...

Technical requirements

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

Blueprint communication

A crucial aspect of blueprints is their ability to communicate with each other. Their true power of interaction lies in communication. Imagine creating an immersive experience where you control characters or pawns, needing to interact with other blueprints to perform various actions, such as opening doors, turning on lights, or changing materials.

Even in traditional archviz, where stills and animations are prominent, having knowledge of interactive actors can prove useful. Correlating events, such as triggering complex animations based on specific conditions, can be achieved through blueprints (or animation tools like the Sequencer).

While blueprint communication may appear advanced, it’s not mandatory to master immediately (not for the project we’re developing in this book, at least). As your familiarity with Unreal grows, you can explore these functionalities at your own pace. Embrace the learning journey, as CGI and Unreal typically require...

Level Blueprints

In our previous work, we created a blueprint for a floor lamp. Now, let’s explore how to control it during runtime, which encompasses both in-game interactions and initiating animations. Controlling events is not only valuable for interactive experiences but also for managing animations effectively during gameplay.

What is a level blueprint?

A short recap on what a level blueprint is: a special type of Blueprint that is tied to a specific level in your game or project. It allows you to define and control the gameplay logic and events that are specific to that level. Level Blueprints provide a way to script interactions, events, and behaviors directly within the context of a level, without having to create separate Blueprints for each object or actor in that level. Level Blueprints are used to control the behavior of the level as a whole. They can be used to do things such as activate triggers, play music, control lighting, and so on.

Project –...

Creating an interactive UI with a widget blueprint

As we learned in Chapter 10, a Widget Blueprint is a type of Blueprint in Unreal Engine used to design and create UI elements such as menus, buttons, and more. It provides a visual way to create and arrange UI elements using widgets and interactive components.

These UI elements are designed to be interactive, commonly used as menus or loading screens, but they can also be utilized to interact with the scene, much like certain video games allow.

In our floor lamp project, we will further develop its functionality by creating a dedicated widget blueprint. However, it’s essential to note that widget blueprints have a wide range of applications beyond this project. They can be employed for numerous purposes when creating interactive experiences, making them a versatile tool in game development and other interactive projects.

Project – Creating a widget

We need to create a widget blueprint first; it will be super...

Summary

Throughout this chapter, we have focused on a key skill often overlooked in archviz courses: blueprint communication, concluding our exploration of blueprints. We delved into this subject through hands-on examples and exercises, covering all methods of communication, including casting, Dispatchers, interfaces, and direct communications.

While these concepts are more commonly associated with gaming, they are also immensely powerful tools for archviz artists. They can breathe life into a scene, whether it’s for project presentations or creating animations, even if not intended for interactive tours. Communication enables you to link events, facilitating actions such as connecting the height of the sun to the movement of solar panels and triggering lights to turn on or other dynamic activities. Eventually, we also gained a better understanding of level blueprints and widget blueprints and how to utilize them effectively.

In the upcoming chapter, we will address another...