What is Ambient Occlusion

Remember the time in PC gaming when factors such as polygon counts and textures were the next big thing?

Believe it or not, a PC that could handle these 2 things used to be considered a PC from the future. However, these benchmarks were short-lived, and as gaming progressed in that era, these were pushed to their limits and were soon out of the game.

As technology progressed, developers started finding more ways to make games look better and more photorealistic than they used to.

One of the key components that helped the developer achieve photorealism was the lighting in the games, and how they use it. However, achieving photorealism through proper, realistic lighting was not an easy task. As a matter of fact, rendering character shadows was a much easier task, and that too in real time.

But having every single pixel on the image be a subject of natural light was not an easy thing.

This is where ambient occlusion steps in.

What Does It Do?

Now when you see this option in the settings menu, you might get confused because, for a gamer, this might not matter much. However, the feature is going to provide you with a realistic ambient lighting system. This is done by calculation of the scene, and then deciding what part of the screen should get how much light based on its shape.

I know it sounds technical and somewhat impossible to achieve, but it is not. In simpler terms, ambient occlusion determines just how much light is going to be blocked by a certain asset in the environment.

Keeping that in mind, you also need to understand that this feature does have an impact on the performance, so if you are not running a powerful enough graphics card, you might want to turn it off.

That brings us to the next part where we discuss the different types of ambient occlusions that are there to cater to different hardware types.

Types of Ambient Occlusion

For those who do not know this, ambient occlusion was first introduced back in 2007 when Crysis came out – the game later became the benchmark for several years, because it needed PC that simply was not around at that time. Thus the phrase “but can it run Crysis?” came to being. Even after 11 years, Crysis is still the game that can give a hard time to most of the PCs out there.

The most common type of ambient occlusion that is being used is SSAO (Screen Space Ambient Occlusion) it is common because it is not demanding at all. However, the quality can vary largely from one game to another game, and it largely depends on how the developers implement ambient occlusion in the game.

However, SSAO is just one type of ambient occlusion that is available in the games. There is HBAO (Horizon Based Ambient Occlusion) and then there is HDAO (High Definition Ambient Occlusion) as well. These two technologies are owned by Nvidia and AMD respectively, which also means that they perform better on the respective graphics cards.

Upon closer inspection, you can realize that both types of ambient occlusions are rather similar in what they provide – they are there to give you the best quality of ambient occlusion you can get. But at the same time, the performance hit on the games would be higher.

In addition to that, these are not as widely implemented in games as SSAO.

Last but not the least, there is a new type of ambient occlusion that was recently introduced, and it was called VXAO (voxel ambient occlusion) and it was developed by Nvidia as something that would be a successor to HBAO. Iit is more demanding than today’s standards, and in addition to that, it also requires a better, higher-end GPU to power it without any issues whatsoever.

Should You Use Ambient Occlusion?

Now that you know what ambient occlusion does, the question arises. Should you use this feature? Well, to be honest, the answer completely depends on the PC you are running. On PCs that are not powerful enough, it is the safest bet to turn off this feature because why would you want to get lower frames just for the sake of having your games look pretty.

Like I have said before when it was introduced first in Crysis, the game itself was way more powerful than the hardware of that time – that is the reason why it was nearly impossible for computers of that age to handle ambient occlusion.

However, things have changed a lot as graphics cards are also becoming increasingly more powerful, and are slowly supporting their own technologies that help them perform better, and give the same results, if not better.

So, the last question anyone could ask here is what type of ambient occlusion is the best one there is. Well, like I have said it before if you have an AMD card, then you should go for ambient occlusions that have been developed by AMD, and if you have an Nvidia card then you should opt for their developments.

If your cards don’t support either of the ambient occlusions, then you should just use the SSAO and you would be good to go.

Moving on, I am only going to say that with the gaming technology moving forward, and companies like Nvidia, as well as AMD, bringing in new graphical improvements, it will not take a long time before we see something better than ambient occlusion or maybe even more upgraded, and advanced version of the same tech.

After all, Nvidia recently announced ray tracing for the Volta series GPUs, so we can only say that the sky is the limit, and for all the right reasons.

Are we heading closer to photorealistic games where you can’t tell the difference? It seems like it is too early to say something.