3D Model of the Month - Remeshing & Alpha Baking (The Game Restaurant Series #03)

Introduction 

Continuing with our Game Restaurant Series, this month we are focusing on the multiple chain-link structures found within the scene.  
While these meshes are not overly complex, they contain unnecessary geometry that can quickly add up and negatively impact performance.

In this edition, we will show how RapidPipeline’s  Remesh and Bake Holes action was used to optimize the chain-link structures in our Unreal Engine scene, therefore reducing multiple meshes’ complexity while preserving visual fidelity.

The Problem

Models containing chain-link structures are typically created with a high polygon count to achieve a realistic look. As a result, the final mesh tends to be dense. In our Restaurant Scene for example, these structures range from having 160k polygons, all the way to over 380K polygons.  
Since some of these assets are reused throughout the environment, the total geometric cost can quickly increase, noticeably impacting the performance of the final scene.  
In this case, simply decreasing the polygon count is not that effective of a solution. Because of the thin geometry, aggressive decimation can alter the appearance of the asset, meaning we would be sacrificing visual quality for performance. 

The Solution

Instead of simply reducing the polycount of the entire model via decimation, a more suitable approach for this model would be to use RapidPipeline’s Remesh and Bake Holes action. This action remeshes the entire mesh to a lower face count, generates new UVs and bakes the chain link details of the mesh into a texture with an alpha channel.

For such meshes, this is a very efficient method for optimization as it allows us to preserve geometrically complex parts as lightweight textures.

For some models, this can reduce their overall polycount by over 90% without losing detail. The chain-link fence below for example, initially had over 380k faces and by using this workflow, it was reduced to less than 10k polygons.

Results

The remesh and bake alpha action allows us to optimize every model with a chain-link structure within our scene without losing detail. By replacing dense geometry with baked alpha textures, we significantly reduced the overall geometric cost of the Restaurant Scene. The result is a much lighter environment that runs more smoothly in Unreal Engine, while maintaining the same visual quality. 

Input

To showcase the results outside of Unreal Engine, we can use the plugin’s export action to export the file in our format of choice. You can check out the final version of the model using our interactive viewer below. The results can also be viewed in AR:

Meet the Author

Daniel

Technical 3D Artist

Daniel is a 3D and VR artist and responsible for QA at DGG. Working with leading retailers, DGG is on a mission to automate 3D asset optimization workflows for Web, mobile and XR targets - for e-commerce, and beyond. Daniel completed his studies in Expanded Realities at the Hochschule Darmstadt.