Fake it ‘til You Make It: Faking Extended Draw Distance in Mobile Games

Developers of Block City Wars demonstrate a clever use of shaders and fog effects to fake distant objects, optimizing draw distance for better performance. In this game, players must be able to see the entire map from any position to avoid being at a disadvantage. Simply increasing the far clip plane isn’t feasible, as it raises the number of triangles passing through all culling stages. This means more objects undergo bounding box checks on the CPU and more fragments are processed on the GPU.

I encountered a similar issue while developing a car simulator set in an open city. We struggled because of the need to support multiple monitors, requiring separate cameras for forward, left, and right views, along with additional cameras for rearview mirrors.

Why not use a single camera with an ultra-wide FOV for forward, left, and right views? The answer is straightforward: to render 180 degrees, the FOV must be extremely high, resulting in unacceptable image quality due to severe distortions. This approach looked particularly bad on multiple monitors.

Instead, we opted for a combination of LODs, impostors, fog, and shorter draw distances for the left, right, and back cameras. Since players primarily focus on the forward view, this compromise worked well. And what was easier was that we didn’t need to render important objects all the time, as it was not needed for players to orient themselves using them.

https://www.gamedeveloper.com/production/fake-it-til-you-make-it-faking-extended-draw-distance-in-mobile-games

However, it’s unclear whether the solution includes LOD support for scaled-down meshes. If the distance is faked by scaling objects, then the high-poly version should be rendered, leading to high vertex density. This introduces performance challenges, as detailed in previous posts:
Vertex density
https://t.me/everydayUnity/1634

Tips from the latest Unite https://t.me/everydayUnity/2441

#rendering #culling