Sea Power Dev Diary #4 – Widened Horizons
The global vistas of Sea Power
Originally we had designed the game around a compressed-distance concept where 1nm = 1km. While the intent was for faster gameplay, we quickly found some issues particularly pertaining to the speed with which engagements happen at modern speeds. This approach also necessitated some internal recalculations particularly as we use a global world with longitude/latitude coordinates for reference, and generally became rather confusing, so the decision was made to scrap distance compression altogether and simply make the world 1:1 scale. We originally had a rather short draw distance, and this had the unintended side-effect of making our environments look a lot more bland due to the fact that terrain features are now spread out over twice the distance. The solution was to increase draw distance two-fold, and it became necessary to rethink the way we approach our terrain.
Being a former radar operator who worked both with Soviet search radars (P-35) and later RRP 117 (a variant of the US AN/FPS-117 Long Range Solid-State Radar) this felt like coming home!
Proper sensor modelling is one of the most important topics for any war game as it makes the difference between survival or loss of your own units. As real sensor computation is pretty time consuming we decided to go with a model using so called RCS values (Radar Cross-Section). Those RCS values basically measure how detectable an object is by radar. It depends mainly on factors like material, the size of the target and the angle to the radar transmitter plus some other things I don’t want to go into detail here. Every object in game will have such a RCS value.
So how is that radar image created using RCS?
For every search radar on any vessel/aircraft we collect all RCS values of objects which are in range. In range means here the radar horizon based on the height of the radar plus the height of the target plus minimum and maximum reachable height values for the radar itself.