This is the very first technical showcase of the rain effects system built for ATG: Kish - the open-world vehicle and lifestyle simulator set on Kish Island, Iran.
Dynamic Rain System
Rain is a significant atmospheric element that transforms the driving experience. For ATG: Kish, building a believable rain system was a priority from early development. This post showcases the earliest working demonstration of the dynamic weather technology.
What Makes This Technically Interesting
- Realtime particle simulation - rain drops computed in real-time using Unity's particle system
- Surface wetness shader - roads and surfaces respond dynamically to rainfall
- Windshield water interaction - the precursor to the full DriveClub-style windshield FX (see the dedicated post)
- Physics integration - wet road conditions affect tire grip through the VPP physics layer
- Atmospheric scattering - rain affects visibility and lighting in the scene
The Evolution
This early rain system laid the groundwork for the much more advanced water-drop windshield FX that was later developed and released free to the community. The iterative process of building and refining these effects is a core part of ATG: Kish's development philosophy - build it properly, share it with the community.
What's Next
Weather systems in ATG: Kish will eventually include:
- Dynamic rain intensity (light drizzle to heavy storm)
- Weather transitions in real-time
- Puddle accumulation on roads
- Hydroplaning physics simulation
- Fog and mist effects for coastal Kish Island atmosphere
Dan