You are sitting and playing your favourite 3D game, and you notice edges of all the subjects on the screen sharp, edgy and not smooth. Have you ever wondered why it appears like that? Have you blamed your graphic card or your desktop for the same reason? The answer you are looking for is called ‘Anti-aliasing’, which causes such glitch with your subjects on the screen when kept low/medium in the game settings.
To know what Anti-aliasing is, you need first to understand what aliasing is. It’s a fairly complex subject, but I’ll try to give you the highlights.
In digital signal processing, aliasing is the effect that causes two signals of different frequency to become indistinguishable during sampling, While in computer graphics, Anti-aliasing is a software technique for diminishing jaggies – stairstep-like lines that should be smooth. Jaggies occur because the output device, the monitor or printer, doesn’t have a high enough resolution to represent a smooth line. Suppose you are playing a game in a low/medium setting; you will start noticing the edges of the objects are sharp and not slippery (jagged edges). It might be because your Anti-aliasing settings are low for your game. Anti-aliasing reduces the influence of jaggies by surrounding the stairsteps with intermediate shades of grey (for grey-scaling devices) or colour. Although this decreases the jagged appearance of the lines, it also makes them fuzzier.
Let’s understand the different ways in which Anti-aliasing techniques work for 3D game rendering:
- SSAA (also known as FSAA): Super sampling anti-aliasing was the original type of anti-aliasing possible. It’s helpful with photorealistic images but isn’t very obvious in games anymore because it utilizes processing energy.
- MSAA: Multisampling anti-aliasing is one of the standard models of anti-aliasing obtainable in modern gaming. It can smoothen down the edges of only polygon shapes, and that is why its processing compared to SSAA decreases. (MSAA still uses quite a bit of energy, though.)
- FXAA: Fast approximate anti-aliasing, comes with minimal production cost and evens edges in all image elements. Although you are looking for great crisp graphics, this is not made for you as it provides a bit blur images.
- TXAA: (Stands for Temporal anti-aliasing) It only runs on certain graphics cards but combines with ample different methods to even outsides. It works better but still has some carries blurriness and uses a bit more processing power.
These algorithms provide different names based on their work, like MSAA, FXAA, TXAA, SMAA, etc. Some are more computationally expensive than others. FXAA is a popular choice nowadays since it is computationally cheaper while giving higher visual fidelity. While TXAA introduced by Nvidia gives photorealistic results and is the most power-hungry.
How does an Anti-aliasing setting works in your games?
The Anti-aliasing settings use a lot of GPU power and consume more Frames as we increase the aliasing settings too high. Tweaking aliasing settings may boots or consume a lot of game frames. For each Anti-aliasing settings, there is x2,x4,x8 option. It means as you increase the rate of Anti-aliasing, the smoother the image becomes by removing jaggies formed by the edges of polygons and other lines.
How does 3D rendering happen through Anti-aliasing?
3D video games render to display on a 2D surface (TV, Monitor). What you see is an illusion of three dimensions. Aliasing is a side effect of this approximation. The lower the resolution, the larger the pixel size and hence the more pronounced the product.
The quality of your image outcome depends on how efficiently the algorithm implements into game code. And how powerful is your GPU? TXAA is exclusive to Nvidia, so in practice, you need both games to implement TXAA and GPU to support the algorithm.
Because each frame is produced separately to reduced aliasing, it becomes resources intensive to do so.
How will understanding the algorithms for your game help?
If you went through the whole article and grasped some knowledge, the next time you visit a store for better graphic configurations, the understanding of algorithms will help you choose the best AA for your device. You get back home happily, kill those opponents with guns that will be looking fine and not sharp because you choose the best AA for you.
Do you like playing games with good graphics or with bad ones? Do you want your subjects on the screen with sharp edges or with smooth ones? The moment you understand how the rendering works in your favorite game box, that day, you will know which graphic configuration you need. The more curious you get to explore the setting of your games, the deeper you understand it. It’s all about the rendering and how it works—interested enough to read about how your game renders?