Hi,
i´ve been working on implementing Imposter Rendering in Unity lately. Please have a look:
Its real Imposter Rendering (see: news) with dynamicly updated Textures based on the Camera position. No precalculations needed! I´m currently working on the caching and preloading of the Imposters. You can check the current Version here: https://dl.dropboxusercontent.com/u/40550065/Imposter/Web.html (Webplayer Demo). I´ve been thinking about releasing it on the Asset Store - what do you think?
That’s fantastic! Well done 
This is incredible! I get a 2000% fps increase on my work pc! From 4fps to 80fps on the highest object count. Really impressive. Good job!
I have been wanting a easy solution for imposters for a while, they are a great way to kill two birds with one stone,
Give the illusion of a fuller scene with great draw distance and deliver fantastic performance.
If you do release on the asset store this is a instant buy from me.
This type of system will probably be mandatory in some of my personal projects at some point. I’m looking forward to seeing how this develops
VERY impressive! The savings are phenomenal. Nice work.
I agree this is amazing…please release this!
Agreed this would be a great addition to unity. Would buy no hesitation.
The problems are when to regenerate, how to re-use the same render texture, and avoid stalls when updating it.
But the idea is great!
As for asset store, well, it would probably sell if you make sure the mentioned items are properly handled.
My guess is between 50-100$. While that might sound much, most buyers will be artists who can’t/don’t want to spend time on it, or people who need/want the optimization and feel that the hours it would take to re-create it is more then what they pay for the asset.
Would buy in a hearbeat! Looks great!
Fantastic, a great plugin for complex scenes that will save lot of frame rate.
The price is a bit too much i think above 50$, i will stay with simple LOD that will also do a great job when your farther LOD is as simple as some cubes.
A 3d version of it already exists, and if the OP decides not to release his, I’d be happy to make and release a imposter system, just dont want to be an ass and compete.
@Zicandar i own your solution but it didn´t exactly fit my needs so i decided to build my own. I’m planning to release it in the Asset Store soon. Just finishing up the documentation. I think i will sell it for ~40$
@Zicandar the biggest problem for me was supporting dynamic shadows & handling the Z-Occlusion right (prevent the imposter from penetrating the ground). A System for Texture reuse was indeed crucial. I also implemented Texture batching (use a large texture for several small render targets) but it didn´t help a lot.
Any update?
Some thoughts:
5.2 culling groups functionality should be able to improve the state affairs quite a bit especially with distance bands and querying visibility.
It’s not really viable or good for a lot of objects like in the demo scene. Ideally with distance bands you’d be able to cluster several separate objects into one imposter if necessary.
It’s probably a much better fit for rendering mountains and large polygonal areas as it will take a while to get there, and rotation artefacts are minimal.
Not sure on changing lighting conditions but this is an overall problem with open world.
One of the issues in the demo would be when you rotate too quickly, this can cause framerate to tank, so it’s probably best to lazy update or put a cap on updating… other than this it’s a great start and may very well be great for characters as well, for example an army…
Regarding point 2: the performance gains can vary on a modern GPU, it can be that there’s a loss of performance due to the overhead of say 1,000 objects being managed (specially when turning) vs just having low poly lods which don’t require rendering to texture.
In isolation, it’s clear there’s performance benefits from imposters but lots of imposters may be slower than just effective lod management and not having to render to texture / burn ram… when compared to a correctly set up scene with LODs.
But imposters can really save the day when it comes to distant rendering of terrain as seen in far cry 2, 3 and 4, where they impostor most of the terrain in the far view.
Essentially it’s currently better than not doing anything at all, but it’s not wise to use it for a lot of objects unless it’s situational and they have to animate. One good example is you render a few soldiers in various angles while they animate and can then approximate an army that’s animated for low cost.
Another issue with imposters vs just having a low poly representation is that there’s no depth and lighting can quickly become incorrect. You will also have issues for example if another object passes behind or inside a distant imposter vs just having say, a 100 poly mesh which likely costs exactly the same as the imposter to render.
If your system is using dynamic batching, then this is also solvable with LODs if groups are clusterable. I’m not knocking the system, I’m just saying that it’s a great addition not replacement for the benefit of any readers.
Finally, I was assuming that your approach uses one texture for several objects, by that I mean it’s atlased within.
@hippocoder I’m not sure if i get your point. Yes, if you have a cost effective way to reduce your highpoly objects (25.000 tris in the demo) to only 100 Polygons while using just a single texture and without sacrificing visual quality when having a object screensize of 256x256 pixel, you should obviously do it instead of using imposters.
But IMO most Indies can´t do this and will benefit from a solution where they just need to drop a script on the Gameobject and be done.
I also don´t think the system burns RAM - 48x48 objects active need 50mb RAM on runtime (no preprocessing required). This isn´t even a problem on mobile.
But i totally agree with yout point that every LOD System has its own benefits and i would never claim that imposters are allways better suited than mesh based lod algorithms. After all i spend most of my academic life developing mesh based LOD systems.
Nice job!
I haven’t met until now such a good implementation of imposters for unity.
Instant buy from me.
