Anti-Aliasing 101: What is Anti-Aliasing? (& What Does it Mean for Gamers?)

What is Anti-AliasingNeed a quick primer on anti-aliasing? In this guide, we’ve covered what anti-aliasing is and how impacts you and the games you play.

Do you enjoy playing PC games? If so, you’ve probably found yourself adjusting the graphical settings at one point or another. While most of these settings are self-explanatory, some might not be if you’re unfamiliar with adjusting computer graphics. An example is the “anti-aliasing” setting. In fact, you might have messed around with it but couldn’t see a noticeable difference in your game. So what is anti-aliasing, and how does it affect how your PC games look?

Understanding Anti-Aliasing

There’s a lot to take in about anti-aliasing. In fact, there are many different types. Before getting into them, it’s important to understand what anti-aliasing does and how it improves gaming graphics.

First, you need to know what aliasing is. In an image, it’s a jagged edge. You may have noticed aliasing in a PC game when a line that’s supposed to curve looks like a set of stairs instead. This is what many people in the PC gaming world refer to as “jaggies.”

Aliasing
This example from Worcester Polytechnic Institute shows the challenge game developers have in rendering smooth-looking graphics on a square-pixel-based display (which is all modern displays).

Why do jaggies form? The main reason is because the computer screen or output device is made up of a large number of pixels. Each pixel is rectangular in shape. When it comes to making lines that curve or are rounded, the rectangles cause jagged edges.

It stands to reason that anti-aliasing technology aims to resolve this jagged-edge problem. As monitors and other output displays receive advancements in resolutions, aliasing is harder to notice. The number of pixels increase to the point that the jagged edges shrink and are virtually unnoticed by the naked eye. In fact, that’s why some people don’t notice a difference in how their modern games look when they mess with the anti-aliasing settings. For others, however, turning off anti-aliasing reminds them of just how disruptive aliasing can be.

How Does Anti-Aliasing Technology Work?

In the real world, we’re able to see smooth curves. As explained above, these smooth curves are hard to render on a monitor that’s made up of rectangular pixels. For this reason, curved lines in games tend to have a jagged appearance.

Anti-Aliasing
This image, from geforce.com, shows the effect that anti-aliasing has on a graphic. The aliased version of ‘A’ has jagged edges, while the anti-aliased version of ‘A’ has blurred edges. If you don’t think that the blurred edges look good either, you have to consider that as you zoom further out, the anti-aliased ‘A’ will look sharper than the aliased ‘A’.

Anti-aliasing attempts to solve this problem by smoothing out the edges. That’s why some people notice a slight blurring effect around the edges of images in their games. This is anti-aliasing hard at work to make jagged edges as smooth as possible.

Anti-aliasing Example
Here’s a good example of the effect anti-alising can have on the graphics of a game. For an even better representation, check out the interactive version of this image on geforce.com.

However, how does anti-aliasing smooth out the edges? While there are different types of anti-aliasing in general, this technology works by sampling the pixels around the edges of an image. By using the colors that it samples, the technology blends away the appearance of jagged edges.

Different Types of Anti-Aliasing

While the general idea behind anti-aliasing is the same, there are many techniques. Getting the best result out of anti-aliasing depends greatly on the type of hardware that you have and its capabilities. Let’s take a look at some of the most common anti-aliasing options:

Supersamaple Anti-Aliasing

By far, this is one of the most effective anti-aliasing techniques available. SSAA makes your graphics processing unit (GPU) render games at a higher resolution. From this larger resolution, it downsamples the image. Rendering this higher resolution also increases the number of pixels that it displays, which creates a sharper image for the eye. While SSAA is a great option, it requires a high-end graphics card and usually additional video memory. Basically, you need a powerful PC in order for it to work smoothly.

Multi-Sampling Anti-Aliasing

While SSAA is one of the most effective anti-aliasing techniques, MSAA is one of the most common. This option balances performance and quality. It uses geometric shapes and color manipulation to create the illusion of smoothness. With MSAA, you have to choose the number of samples, which is usually two, four or eight. The higher that the sample count is, the higher that the picture quality becomes. However, a higher sample count has a bigger impact on PC performance.

Fast Approximate Anti-Aliasing

Do you want anti-aliasing but don’t have a high-end PC? FXAA might be for you because it’s the least demanding on PC resources. Instead of running calculations on the colors and geometry of a game, it simply blurs the jagged edges. As a result, it typically produces an overall blurrier looking image, but you won’t notice much, if any, performance impact.

Coverage Sampling Anti-Aliasing

Some anti-aliasing techniques are developed by graphics card manufacturers. One example is CSAA, which was developed by NVIDIA. The results are on par with MSAA at a high sample count, but it only requires the performance cost of MSAA at a low or medium sample count.

Enhanced Quality Anti-Aliasing

Like CSAA, EQAA is an anti-aliasing technique developed by a graphics card manufacturer. In this case, the manufacturer is AMD. The results are very similar to CSAA. It delivers high-end MSAA results but requires fewer PC resources.

Temporal Anti-Aliasing

This is a relatively new type of anti-aliasing that’s only seen in newer graphics cards. TXAA actually combines several techniques that other anti-aliasing programs use to smooth out edges. It isn’t very demanding on processing power and provides a better picture than FXAA. However, you’re still likely to notice some blurriness.

Which Anti-Aliasing Technique Works Best for Your Setup?

With so many anti-aliasing techniques available, it can be hard to determine which one is right for you. If your computer can handle it, then SSAA is your best bet. If you have an AMD or NVIDA graphics card that features EQAA or CSAA, respectively, and your computer can’t run SSAA, then that’s the optimal solution for you.

If you’re running a mid-range PC and don’t have access to EQAA or CSAA, go with MSAA. For everyone out there who has a low-end PC, stick with FXAA if you want some kind of anti-aliasing measure. However, you might prefer the aliasing over the blurry image that FXAA creates. The choice is yours and will depend on your GPU more than anything else.

Keep in mind that your display setup will have an impact on aliasing as well. If you’re playing games on a full HD display that’s only 21 inches, for example, you won’t notice much aliasing anyway. If you’re playing games on a 40-inch TV at 1080p, though, you’ll get a lot more aliasing. The bigger that your TV is, the sharper that you need the resolution to be in order to prevent jagged edges. 2K and 4K monitors and TVs will produce far fewer jaggies because of their high pixel density.

Don’t Spend Too Much Time Worrying About Anti-Aliasing

Years ago, anti-aliasing was a big deal. With better graphics and higher resolution displays, it’s becoming a thing of the past. In some cases, newer games don’t require anti-aliasing at all. Despite that, it’s a good idea to understand what anti-aliasing is so that you can make informed decisions about balancing the performance and visuals of your next PC game. Knowing the different techniques can also help you if you ever design your own game.

Hey, I’m Brent. I’ve been building PCs and writing about building PCs for a long time. Through TechGuided.com, I've helped thousands of people learn how to build their own computers. I’m an avid gamer and tech enthusiast, too. On YouTube, I build PCs, review laptops, components, and peripherals, and hold giveaways.

Tech Guided is supported by readers. If you buy products from links on our site, we may earn a commission. This won't change how much you pay for the products and it doesn't influence our decision in which products we recommend. Learn more