What Is Cursor Tracking?

Cursor tracking is the foundational technology that makes most advanced screen recording effects possible. At its core, it is a polling or event-listening loop that captures the cursor's (x, y) coordinates on screen at a high enough frequency to drive smooth downstream effects. On macOS, cursor tracking can be implemented at several levels: using Core Graphics event taps (which intercept events before they reach applications), NSEvent global monitors (which receive events after application dispatch), or Quartz event services. The choice of API affects both the accuracy of the tracking and the permissions the app requires from macOS.

The raw cursor position data from tracking is consumed by several different subsystems in a screen recorder. The auto-zoom system uses it to determine where to center the zoom frame on a click event. The cursor spotlight system uses it to position the glow overlay on each rendered frame. The cursor smoothing system uses it as input to an interpolation filter that produces a smoother output path. The click animation system uses the position at the moment of a click event to anchor the visual indicator. Each of these downstream consumers has different latency and accuracy requirements, which is why robust cursor tracking systems buffer and timestamp events precisely.

Limelight uses macOS system-level event hooks for cursor tracking, giving it frame-accurate position data that it uses simultaneously to drive auto-zoom anchor points, the cursor spotlight position, and path smoothing. Because it works at the system level, tracking works correctly even when the cursor moves over full-screen apps, game windows, or other contexts where normal application-level event monitoring would not receive events. Users do not need to configure anything — cursor tracking is active automatically whenever Limelight is recording.