Found what I was looking for: https://pixelpeeper.com. Source: about 1 year ago

I run https://pixelpeeper.com on the side. It's a micro-SaaS for photographers who edit in Lightroom. Lets you reverse-engineer Lightroom edits from JPG files and download them as presets that you can apply on your own photos. Took a month or two to reach $2k/mo, riding the wave of instagram's popularity in 2017-2018, plus the project went viral initially. However, the niche is ultimately too small to grow the... - Source: Hacker News / about 1 year ago

Alternatively https://pixelpeeper.com/ would show you this in a more useavøe fashion. Source: over 1 year ago

Not to mention DirectX WARP https://learn.microsoft.com/en-us/windows/win32/direct3darticles/directx-warp. - Source: Hacker News / 1 day ago

In addition to ISPC, some of this is also done in software fallback implementations of GPU APIs. In the open source world we have SwiftShader and Lavapipe, and on Windows we have WARP[1]. It's sad to me that Larrabee didn't catch on, as that might have been a path to a good parallel computer, one that has efficient parallel throughput like a GPU, but also agility more like a CPU, so you don't need to batch things... - Source: Hacker News / 8 months ago

If you select a WARP driver it should "theoretically work". But there are some limits with the WARP devices (https://learn.microsoft.com/en-us/windows/win32/direct3darticles/directx-warp). Source: over 1 year ago

If you use D3D11 or D3D12, those come with a software rasterizer by default so you can do graphics programming even without a GPU. It's called WARP and it's what Windows uses to e.g. Render the desktop and stuff before you install your graphics drivers. Source: almost 2 years ago