Beneath the struggling graphics of your favorite games are a multitude of settings that can boost resolution and optimize graphical output. However, bringing out the full potential of your machine requires some knowledge of what these settings do. If you’ve looked through the options of a contemporary game, you probably have some questions like, what is anti-aliasing, and how can it improve my experience?

What is Anti-Aliasing?

If you’re a game fanatic, you’ve probably come across blurred, pixelated edges while playing on your PC. Have you ever wondered what the cause of this is?

These pixelated edges are called “jaggies.” They cause low resolution in computer graphics and are the main reason your game seems to have a shimmering texture or staircase effect.

We also call this phenomenon aliasing, and it happens due to poor sampling or when a signal component has a frequency above 6.2kHz. Aliasing errors are often difficult to detect and almost impossible to remove.

The only solution to remove such errors is to increase the sampling rate using anti-aliasing filters and techniques. Anti-aliasing is a technique that smooths out the edges seen in images while playing games on a PC. It makes them appear less blurred and blends colors to make visuals look natural.

What Does Anti-Aliasing Do?

A PC display is composed of pixels, the smallest element found in a digital image. Despite the high resolutions and millions of pixels in modern monitors, they still leverage rectangular display methods. Even if circular shapes are on the screen, they will always possess jagged edges.

Every image your computer displays is a mosaic of thousands of colored pixels. Creating images with vertical and horizontal lines is an easy task since square pixels are correctly aligned when placed together. However, it is challenging to create an image with curves and horizontal lines since objects consist of many diagonal lines. To create an image with diagonal lines, the alignment of the pixels needs to be point to point, thus, forming jagged edges.

Suppose you’re playing a game with high resolution; you’re less likely to encounter jagged edges or jaggies since it contains enough pixels to smooth out the edges, making it less visible.

The image demonstrates the jaggedness of edges. Source

Why Do Gamers Need It?

Despite having screens with high resolution, gamers still need anti-aliasing. Larger monitors often suffer without anti-aliasing due to the sheer number of pixels they display. If your gameplay experience is suffering due to inconsistent visuals, try out some of the following anti-aliasing techniques.

Most game settings are self-explanatory, but you still need to understand how the combination of anti-aliasing features, monitor type and the game you are playing work together.

Filters

An anti-aliasing filter checks specific sampling frequencies and eliminates any under-sampled variables. According to the Nyquist theorem, the sampling rate should be equal to or greater than the component in a signal. If these variables aren’t met, the frequencies are likely to produce unwanted visual effects.

A low pass filter allows low-frequency signals to pass and reduces frequencies higher than the Nyquist frequency. The right frequency allows the system to measure the sampling rate correctly and prevents aliasing component sampling. An aliasing error takes place when elements of a signal exceed the Nyquist frequency.

Stair-stepping edges seen in images with low resolution demonstrate an aliasing effect.

The left letter is aliased and the right letter is anti-aliased. Source

This issue occurs when different signals become aliases of one another during sampling. The main goal of using anti-aliasing filters is to remove unwanted signals. Here are the four parameters required to achieve anti-aliasing:

1. Amount of attenuation or ripple on the passband.
2. Steepness around the transition region.
3. Different frequencies of phase relationship.
4. Amount of the desired filter rolloff.

Image demonstrating actual filter. Source

Filters play a significant role in eliminating aliasing effects and producing functions like noise filters and anti-aliasing for analog-to-digital conversion (ADC).

ADC is a process that allows computers to interact with different analog signals and convert them into a digital form, making it easy to read and understand. Digital information is easy to process, sample and quantize.

Techniques

Multiple techniques can help your gaming rig rectify aliasing issues that negatively impact your visuals.

In the following sections, we’ll discuss some anti-aliasing methods that protect the quality of your images. It’s worth noting that these strategies depend on the quality and power of the system you’re using.

Two Methods

Below are two common anti-aliasing methods:

Spatial Anti-Aliasing

Spatial anti-aliasing helps reduce artifacting when displaying images. This technique requires a monitor that can display high-quality images at certain levels of resolution.

A good monitor needs a display resolution of 1900×1080 pixels on horizontal and vertical axes. The higher resolution a monitor yields, the better image it can create. More pixels provide detailed clarity in your games.

Here’s how it works:

• Take an image with lower resolution filled with jaggies.
• Render this image at a higher resolution.
• Take colored samples from extra pixels that weren’t present in the lower resolution image.
• The higher resolution image reduces to the original resolution, while each pixel receives a newer color abstracted from the samples.

The above process demonstrates how a low-resolution image produces a higher resolution image with correct color accuracy. These colors help blend pixels to make jaggies less visible.

Supersampling Anti-Aliasing (SSAA)

SSAA, also called “full-scene anti-aliasing” (FSAA), is commonly used to process photorealistic images. It allows the image to have a softer look, making it appear more lifelike.

Sharp edges becoming anti-aliased. Source

This method does not work well with images that have numerous horizontal and vertical lines. Also, the image needs processing before smoothing out jaggies. Since gaming requires real-time rendering, SSAA needs extensive computing power to work.

Coverage Sampling Anti-Aliasing (CSAA) and Enhanced Quality Anti-Aliasing (EQAA)

Developed by GPU manufacturers NVIDIA and AMD, these new spatial anti-aliasing methods determine if a polygon is present in an image. They also detect the parts in a polygon to identify if jagged edges are present. Once detected, the pixels with jaggies undergo supersampling. These methods need less processing power and don’t require supersampling of the entire image.

Multisample Anti-Aliasing (MSAA)

When the GPU renders an image, it differentiates between two objects — textures and polygons.

• The GPU draws a polygon that is in a general shape.
• Then it fills it with a texture.

This method smooths the edges of the polygon and not the texture, reducing processing power.

MSAA works perfectly on geometric edges. Source

Although MSAA is a popular anti-aliasing method among gamers, it doesn’t guarantee clear textures.

Post-Process Anti-Aliasing

Each pixel blurs after rendering in post-process anti-aliasing. The GPU detects the edge of a polygon by comparing color contrasts between two pixels. If both pixels are similar, it indicates they’re from the same polygon.

Blurring is effective since it eliminates misaligned pixels, one of the primary reasons that cause jagged edges.

A significant disadvantage of this technique is that it makes the image a bit too blurry and can negatively affect games with dynamic lighting or detailed features.

Gamers prefer using this method due to its rapid speed and low processing power.

Temporal anti-aliasing (TXAA)

Referred to as the “film style technique,” this method is used to smooth each level of motion while moving around a virtual environment. TXAA can be complex since it uses both blurring and supersampling techniques to develop sharper graphics.

Rendering on dynamic/static image. Source

You can produce better images than FXAA or MLAA; however, it requires more computing power.

Morphological Anti-Aliasing (MLAA) and Fast Approximate Anti-Aliasing (FXAA)

Also developed by AMD and NVIDIA, both techniques work in the same manner as mentioned above. MLAA and FXAA are the most popular anti-aliasing methods in the market due to their ability to sharpen graphics using less computing power.

Enhanced Subpixel Morphological Anti-Aliasing (SMAA)

Developed by Jorge Jimenez, a student from the Universidad de Zaragoza, SMAA combines post-process and spatial anti-aliasing to create an image. The images it creates are of higher quality than those produced by FXAA and MLAA.

Blur contrast points and detect patterns like curves, lines or boundaries. Source

It smooths images using the blurring method and sharpens them using supersampling.

Which Type Should You Use?

With multiple options to choose from, selecting the suitable anti-aliasing method is a daunting task. The best way to decide is to identify which games require it, a suitable GPU and the amount you’re willing to spend on each.

Nonetheless, below are some tips to consider:

• Choose SMAA and CSAA if your computer:
  1. Gets overheated.
  2. Has a moderately powerful CPU.
  3. Has lower than 8GB RAM.
  4. Consists of integrated graphics.
• Choose SMAA, MLAA, FXAA and MSAA if your computer:
  1. Has 8GB RAM or higher.
  2. Consists of dedicated graphics.
  3. Has a moderately powerful CPU and GPU.
  4. Provide standard ventilation components.
• Choose SSAA, MSAA and TXAA if your computer:
  1. Has 8GB RAM or higher.
  2. Consists of a CPU with the ability to overclock.
  3. Has dedicated graphics.
  4. Has gaming optimized ventilation (preferably liquid cooling).
  5. Has a gaming-optimized CPU and GPU.

Final Thoughts

Choosing a suitable anti-aliasing technique can improve the quality of your visuals, but as displays continually increase resolution and image quality, anti-aliasing is becoming a thing of the past. In some instances, modern games might not even require it.

How has using anti-aliasing settings improved your gaming experience? Tell us in the comment section below!