MobileGLDebugger

A RenderDoc-style debugger for MobileGL retrace files. It opens apitrace-v6 .trace files (raw, snappy/zlib/zstd/brotli containers) and MobileGL .tgz fixtures (a gzipped tar whose trace.trace member may itself be container-compressed, e.g. brotli), replays the recorded GLES/EGL call stream on a switchable backend, and lets you inspect every call and the full GL state at any event — like stepping through a frame in RenderDoc.

Backends:

• Native OpenGL — the host desktop GL driver (ES-profile context when available, desktop compat GL with ES-alias fixes otherwise).
• MobileGL Espryt (DirectGLES) — MobileGL statically linked, running on ANGLE.
• MobileGL Magma (DirectVulkan) — MobileGL statically linked, running on Vulkan.

Panels:

• API Inspector — two-column view: recorded GL call (with formatted args) on the left, the MobileGL backend-function-table calls it produced on the right.
• Texture Viewer — texture list with zoomable pixel readback.
• Pipeline State — render state (blend, depth, stencil, ...) at the current event.
• Frame Debugger — draw-call grouping and default-framebuffer preview per frame.
• MobileGL Backend State — internal MobileGL state with the source event id (EID) each value was captured at.

Build

Requirements: Windows, Visual Studio 2022 (MSVC), CMake ≥ 3.24, Ninja, Git (third-party deps are fetched with CMake FetchContent).

:: from a "x64 Native Tools" prompt, or after running vcvars64.bat
cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release [-DMOBILEGL_ROOT=...] [-DMGDB_WITH_MOBILEGL=ON/OFF]
cmake --build build

Outputs land in build/bin/ (mgdb_ui.exe, mgdb_retrace.dll, test binaries).

Options:

• MOBILEGL_ROOT — path to the MobileGL repository (default C:/Users/geekerwan/AndroidStudioProjects/FoldCraftLauncher/MobileGL). Needed for the Khronos headers and, with MGDB_WITH_MOBILEGL=ON, for the Espryt/Magma backends.
• MGDB_WITH_MOBILEGL (default ON) — set OFF to build without the MobileGL backends (native OpenGL only).
• MGDB_BUILD_TESTS (default ON) — gtest suites, run via ctest --test-dir build.

Run

mgdb_ui.exe [path-to-trace]

The optional argument auto-opens a .trace or .tgz at startup; otherwise use File → Open Trace… (Ctrl+O). Use the backend menu to switch between Native OpenGL / Espryt / Magma at any time.

Runtime requirements:

• Espryt needs ANGLE's libEGL.dll / libGLESv2.dll on the DLL search path.
• Magma needs a working Vulkan driver.
• Switching backends (or seeking backwards) tears the backend down and replays the trace from call 0 up to the current event — on large traces this takes noticeable time.

Architecture (6 lines)

• mgdb_ui.exe: SDL3 + ImGui (docking) shell; talks to the engine only through the C ABI in include/mgdb/mgdb_api.h — never calls raw gl* symbols itself.
• mgdb_retrace.dll: trace parser + replay engine + GL state tracker + backends, statically linked with MobileGL.
• mgdb_trace: apitrace v6 parser, trace model, container decompression (snappy, zlib, zstd, brotli, tar.gz fixtures).
• mgdb_dispatch: generated invoker that marshals recorded calls onto real GL entry points, plus EGL adaptation onto the host platform.
• mgdb_pal / mgdb_backend: SDL3-based windowing/context abstraction, and the Native / Espryt / Magma IBackend implementations.
• See ARCHITECTURE.md for the full contracts, EGL adaptation rules, and state-JSON schema.