Halo 2 640x480: SSAAx0 vs SSAAx16
This is intended to be watched at 2160p60 (4k). Not for the pixel count, but for the higher bit-rate and better video codec
What is SSAA:
SuperSampling Anti-Aliasing is one of the oldest forms of anti-aliasing (removing jaggies) by sampling each pixel on the screen multiple times and then averaging those samples together to color that pixel. SSAA is the same as scaling a big image down into a smaller image.
Because of it's simplicity, this turns out to be the most accurate (and most expensive) form of anti-aliasing. It is not like MSAA and applied only to geometry edges, or FXAA and TXAA and approximated in post.
All forms of anti-aliasing are limited in some way, either due to high resource use, or low image quality. Because SSAA takes into consideration several real samples in every pixel, there is a benefit to the final color accuracy of every pixel.
Simply put, don't think of it as only anti-aliasing. This method will color each pixel very close to what it truly should have been colored, based on more data gathered from the underlying "source material", than was originally possible.
Why use low resolutions (like 640x480) when we have 4k displays:
In any game, the shaders/assets/textures/art/dynamic effects/ect. are all built around a range of common resolutions for the time. Or perhaps, a specific resolution chosen for a technical reason, such as optimizing memory bandwidth. Because of an array of limitations, it's common for 3D artists and developers to work closely together on what can look the best with their unique set of limitations, goals, and timeline.
Preserving era-appropriate "chunky pixels" becomes important to the overall look. This is why the Goldeneye 007 Remastered at 4k for the Xbox Series X doesn't look quite right... but we would still like to use the added detail from 4k in a 320x240 game (That would be 320x240 with SSAAx18 = 4k - I believe Goldeneye 007 runs at 320x237 in the US and Japan).
• DF Retro EX - GoldenEye 007 - New Xbox Ser...
What makes this version of SSAA special:
Compatibility and flexibility. On Microsoft Windows, there are forms of SSAA available through the GPU driver directly, but, can only downscale to your monitors native resolution. This is being downscaled to Halo 2's original 640x480 instead of only the native resolution of 1920x1080.
There are other 3rd party programs on Microsoft Windows that will allow downscaling to arbitrary resolutions (like 640x480) but are limited by the API used by the game (like DX8/9 only) and many have become abandonware. This release of Halo MCC uses DX11 and is running through Proton.
Rendering Info:
These two videos were rendered at 5120x3840 (That's ~2.4x more than a native 4k resolution. Near 8k, but 4:3 aspect ratio) then downscaled to 640x480 and losslessly captured. They were then composited and upscaled through Kdenlive to 3840x2160 (non-integer) with a linear interpolation filter to be YouTube friendly.
Achieved with ValveSoftware's GameScope for Linux. Special thanks to @RuanFormigoni