Gapir

Gapir is a device-side component of GAPID (Graphics API Debugger) used to replay captured graphics command streams on Android devices for debugging and profiling of graphics applications. Gapir executes traces recorded by the host tooling so developers can inspect and analyze GPU frame behavior without needing to reproduce issues on a per-run basis.

Gapir provides several core capabilities. It loads a trace, initializes the GPU state, and replays the same sequence of API calls and commands that were captured, enabling deterministic reproduction of frames. It supports stepping through commands, inspecting resource lifecycles, capturing per-draw call data, and collecting timing and state-change information for performance and correctness investigations. It communicates with the host-side gapis/gapit components to provide data and receive configuration.

Architecture and workflow: In typical use, a developer uses gapit on a desktop to capture a frame or sequence from an application using Vulkan or OpenGL ES. The captured data is transferred to the device where gapir runs, replays the trace against the device's GPU driver, and streams results back to the host for analysis. Gapir operates within the device sandbox and interacts with the Android graphics stack to replay the commands.

Availability and scope: Gapir is part of the GAPID project, an open-source set of tools for graphics debugging and performance analysis. It supports major APIs such as Vulkan and OpenGL ES and is designed for Android devices, with corresponding host tooling on Windows, macOS, or Linux.

See also: GAPID, Vulkan, OpenGL ES, Android.