Unreal Engine 4 Multiplayer Physics Actor Replication in Blueprints -- Part 1

Yep, probably our longest article title to date.

Multiplayer Network Replication in Unreal Engine is a daunting task. Compared to the "simplicity" of making a single-player game, you basically have to add an extra layer of logic on top of your existing logic. There's also managing and differentiating what should go where among things like player states, games states, and game instances. This guide will show you how to get around some of the more frustrating and less-than-intuitive parts of using UE4 Blueprints to replicate a physics actor pawn in your game.

How to Use Emissive Materials to Light Up Your Levels in UE4 with Blender and Substance Designer

In Unreal Engine you can use emissive materials to help give your meshes some character and light up your game. Basically, if you want your material to give off some light without having to add a lamp to your scene you're going to be working with emissives. This is going to be a short and relatively simple tutorial on how to create meshes in Blender and texture them in Substance Designer so that they can light up in Unreal Engine 4 using emissive materials.

How to Change Parameters in Dynamic Materials at Runtime in UE4 using Substance Designer and Blueprints

Substance Designer is an all-around great tool for texturing 3D models, but one of the features that I'm most excited about in my game development is Substance integration in UE4. Allegorithmic had already integrated with Unreal back in the UDK and UE3 days (I guess technically you can still use UDK and UE3), but they've only recently released a plugin for UE4 that doesn't require recompiling the engine for it to work.

The Substance integration is huge because not only does it mean that you can save time importing textures and creating materials by simply dragging and dropping an SBSAR file into your game, it also means that you can dynamically change any values that you've "exposed" in your Substance graph at runtime.

This is a tutorial on how to manipulate your exposed Substance variables at runtime in your game using a key press.

Blender to Substance Designer to UE4: My Workflow

I like to think my workflow is unique. I use a free 3D modeling program, an engine that comes with a very affordable subscription plan, and a fairly expensive model texturing program (at least relative to my other tools). No Photoshop and no Autodesk products are involved. This is in part because the FBX exporter in Blender doesn't carry over the textures that you use in the Blender material editor to UE4 , and also partly because Substance Designer is a tremendous time saver.

(UPDATE: It seems that the materials in Blender can, in fact, be exported to UE4 now. I only exported a mesh with basic colors [by accident], so I can't attest to what extent Blender's material editor settings will carry over to UE4)

Here is the workflow I currently use to create meshes, texture them, and import them into UE4.

Creating Custom Collision for Unreal Engine 4 in Blender

After you have gone through the steps of readying your mesh to export into Unreal, you may want to consider adding your own collision to your model. Collision, put simply, is what tells your game what parts of your mesh objects can and can't pass through. UE4's collision tools are great, they have even updated the collision creation tool to work with more complex geometry to allow objects to pass through holes in the mesh, but if you want more control over how your collision works, it can be easily done in Blender.

Here are the steps to create custom collision in Blender for use in UE4.

2014 Update and Substance Designer

Substance Designer graph and 2D output windows of a rusted metal wall substance

Substance Designer

After a brief hiatus for the holidays, I have returned to work on our game in the new year with a brand new tool: Substance Designer 4. While this is a bit of a pricey detour from our general “spend no money” policy, I caught a Steam flash sale and couldn't resist the temptation to buy a commercial software license for 66% off the retail price.

If you haven’t heard of Substance Designer, it’s an extremely powerful node-based texturing tool made by Allegorithmic. You can string together nodes to make your substance (e.g., a rusted metal with chipping paint) once, and then save that substance for later use on your other models by simply dragging and dropping the pre-made substance into your new node graph (it will condense the whole pre-made graph into a single node, which saves space) and hooking up the nodes. The 3D view shows you how your model looks in real-time, so it saves time you would otherwise spend hopping back and forth from Photoshop. (I don’t mean for this to sound like an ad for the software, I’m just really excited about this purchase).

Substance Designer is directly supported by UDK, so a major advantage for me is that I don’t have to worry about issues with UV mapping and trying to get my Blender materials to display correctly in UDK. Further, you can “expose” attributes in Substance Designer to allow you to edit how your materials look inside of UDK (e.g., expose the color palette and you can edit the color of your material in UDK), which gives your level designer more power over how assets look inside the game.

The downside is that I am now obligated to learn yet another complex tool. Fortunately, Allegorithmic has released several tutorials for using Substance Designer, so that should take some of the pain out of the learning process.

Introduction

The purpose of this blog is to chronicle the development of our game using the UDK Engine and Blender. First and foremost: we are not experts, we are just two guys who happen to love gaming so much that we decided to try to make our own.

As of now (the format may change in the future), our posts will detail our progress (and lack thereof) in developing our game. This will include tutorials on how to accomplish tasks we’ve found to be especially daunting and random narratives about how we have encountered and overcome various issues in indie game development.

This first post will describe the steps for getting started in making your game, including: preparation, engine choice, and collaboration. In addition, I've given a narrative of the path we chose and explain the decision process that led to us following our specific path.