Hah, that wasn’t tLog or whatever it was called, was it? I recall that Randy Overbeck used it a lot and it was one of the primary drivers of GraphKit being optimised to support hundreds of millions of data points on a single chart (it’s amazing what some clever rasteriser-aware data pre-processing, and the CoreGraphics APIs, can do).

I was pretty proud of that, I must admit. To this day I’m not aware of any charting library that is as performant while still producing technically correct results (meaning not just plot element placement but down to line joins and end caps).

Though of course that was all CPU-based. Presumably now it could be accelerated by GPUs. I vaguely recall exploring that a bit, way back then, but OpenGL wasn’t going to make my life easy if I went that route.

@everything Get out of here, I used GraphKit for a custom internal tool

To be clear, though, I worked on Shark for only a couple of years, and my contributions were modest. I worked in particular on GraphKit, the charting framework that Shark (among other Apple applications) used. And CoreProfile, the framework that was built to support Shark 5 but ultimately only ever got used by Instruments.