PixelMap: Sleeker, Faster Bitmap Editing for .NET
ruarai.com
ruarai.com
It's important not to do too much HSV/HSL color manipulation with an API like this, though - unlike RGBA, which can be altered independently, the Hue/etc properties on the Color type in this library are lossy, because you can't cleanly roundtrip between integer RGBA and HSV (of any precision, really). If you use high precision floats you can roundtrip somewhat more reliably, but it's still a bad bet. So if you first change the Hue and then change the Saturation, you'll get some really nasty artifacts at some points in the color space. (For example, if you try to set the Hue of solid black, it won't do anything.)
A better approach for HSV is to just have a value that represents a point in the HSV color space, and convert it once to/from RGBA when you need to. Do as much in a given color space as you can. (Also, when dealing with HSV you simply need more precision than 24bpp rgb. I typically used 16 bits per channel to reduce the amount of error.)
For cases where you want to do HSV and you care about performance, you could probably use the new .NET SIMD types like System.Numerics.Vector4. Then you'd be getting a perf boost from native SIMD operations and you could carry your channels around as float32.
I ran into the awful performance of the Get/SetPixel methods doing some work with font rendering a while back. The solution I chose ended up similar to the StackOverflow post on linked on the page but it made the code unmaintainable enough that I just abandoned it entirely[1]. I might revisit that next month.
[1] It was a weekend/side project so I was revisiting it after several days and I remember thinking "WTF was I trying to accomplish here again?"