This article in the series focuses on the various graphics settings that we encounter while playing games. The following settings are the ones that are almost always present in all video games. The explanations given are anything but detailed but they’re enough to get you going.
If you’ve ever gone shopping for LCD or Plasma displays, you may have encountered advertisements showing their refresh rates. The higher the refresh rate, the better the TV. This refresh rate is the amount of times in a second a display unit can draw images on the screen. Most PC monitors have a refresh rate of 60 Hz or 60 times per second. Similarly the frame rate of a game is a measure of the number of times a video source (graphics card) can output a new frame of data to that display.
Problems arise when the refresh rate of a monitor fails to sync with the frame rate of the video source. Say for example, your game is running at an average of 40 frames per second while your monitor is refreshing at 60 Hz. You will notice that as you look up and down or move sideways with your character, the screen will tear at the middle for a fraction of a second. This phenomenon is known simply as screen tearing and this visual artifact is worked around by an option called V-sync or visual synchronization.
V-sync, as its name suggests synchronizes the monitor’s refresh rate with the video source’s frame rate. While it does take care of that visual blight, it limits your game’s frame rate to that of the monitor’s RR. This stands as a serious issue if your game’s frame rate is less than the monitor’s RR because to compensate your game’s frame rate may be halved which may render it unplayable. It is advisable to use V-sync only if your game’s fps (frame per second) count is well above your monitor’s refresh rate.
This is probably the best known graphics setting of all. Antialiasing is a way to reduce jagged edges on polygons that make up virtual objects in 3D environments. The reason jagged edges (or aliasing as it is known) exist is because of the difference between the resolution of the source image with that of your screen. As you increase your monitor resolution, the pixelation of that object decreases as the number of pixels used for that object increases. And so, the numbers of those rough edges decrease.
Antialiasing is a graphically demanding task and tends to use up great amounts of visual memory and GPU (Graphics Processing Unit) calculations. High levels of antialiasing can severely affect gaming performance and that is why all games are flexible when it comes to customizing antialiasing levels.
There are a great many types of antialiasing available with optimizations being done for every new method. Graphics card makers NVidia and AMD are constantly on the run to make newer, faster antialiasing methods to balance image quality with high performance. Notable examples are: MSAA, FXAA, MLAA, etc.
Anisotropic filtering is a way to better present textures far away or at oblique angles from the viewer. Antialiasing does the job of smoothing out jagged edges and anisotropic filtering does the job of enhancing the textures themselves. It makes those far away low resolution textures blend in with the textures that are relatively near to the player so as to provide a plane where both textures don’t look too different from each other. There are three types of AF – bi-linear, tri-linear and full AF from 2X to 16X sample rates. Higher levels of AF provide clearer and sharper textures. It is however GPU intensive but recent optimizations in AF algorithms have made it possible to use AA along with AF without sacrificing too much performance.
Whenever you’re installing any game on Windows, you’re advised to install or update DirectX. So what exactly is it? Before going into that, you must first know what an API is. An API or Application Programming Interface is basically a set of rules that software programs make use of to communicate with each other, sort of like hiring specialists to do work for you.
DirectX is a collection of these APIs made my Microsoft to handle tasks related to gaming and multimedia. Each time you update your DirectX, you’re updating those APIs to better support that game. The name Xbox originates from DirectX as the console uses a custom version of DirectX.
There have been many versions of DirectX. Even today most games rely on DirectX 9. Newer games support DirectX 10 and above. The later versions of DirectX have unique features such as Tessellation and Multithreaded rendering.
DirectX 11 Tessellation
Ambient occlusion in 3D computer graphics is a shading method that tries to imitate the way light radiates in real life. Light bounces of surfaces depending on the property of that surface. A piece of coal will reflect less light than a slab of marble. This greatly helps in adding realism to 3D models as the attenuation or loss of light is taken into account. AO makes character models and objects look much better but at the cost of performance.
Two notable forms of ambient occlusion are HBAO (Horizon Based Ambient Occlusion) and SSAO (Screen Space Ambient Occlusion). Ambient occlusion is highly GPU intensive and like antialiasing it is being optimized upon.