KT - Impostors

To efficiently render large environments, I implemented an impostor system to represent distant geometry with significantly reduced draw calls
Instead of rendering full-resolution meshes, assets are batched and simplified, allowing us to reduce rendering cost at long distances

Features

Type-Based Simplification

Each asset category is processed using custom reduction rules to preserve its visual silhouette at distance.

Texture & UV Optimization

For buildings, I implemented a full UV recomputation and texture baking pipeline to:

• Improve texel density consistency
• Maximize UV space usage

Additionally, I developed a Houdini algorithm to detect triangles with near-uniform color.

• These faces are excluded from UV repacking and texture baking
• Instead, they are reassigned to the closest matching color in the texture

Terrain Integration

Small assets such as rocks are baked directly into terrain textures, including height modifications, reducing both geometry and potential draw calls
Level artists and designers can also specify mesh parameters so some assets keep their last LOD in the impostor pass, preserving details on tall structures

Vertex Data Optimization

Whenever possible, I shift data from textures to vertex attributes:

• UV channels used for roughness / metalness
• Vertex colors used for uniform assets (ex: roads)

This reduces texture memory usage and improves rendering performance

Impostors LOD 1

On top of that, for very distant tiles, I bake tiles 2 by 2 and further reduce geometry and texture usage

In-Game Impostor Context

Here's a small video showing the approximate distance at which impostor meshes are meant to be rendered

Final optimized look