Hey,
In this article (Managing Memory | Joseph Stankowicz) it suggests you to bake light maps and then not calculate any normals in order to save memory.
So I have a huge scene on iOS with over 2 million triangles and a big ram problem on older devices. So I am wondering whether I am really going to save Ram space by generating lightmaps. Are those really taking less memory then normals?
You will increase performance if your objects are casting shadows in realtime. But when you say that you have a scene with 2 millions polygons, I think it’s way too much for mobile.
Does your polygons are visible in the same time ?
If you want to go further I suggest you to look at the different parts of this guide: Unity - Practical Guide to Optimization for Mobiles
Thank you for the answer. Well I have 2 million visible and 4 million total in the scene.
I am totally aware that this is a huge number for the older devices, but I improved the overall performance so with batching, optimized shaders and so on. So it runs quiet well except on iPhone 4S and iPad2 with iOS 7. Strangely Unity will then increase the Ram usage by almost 60mb.