cpp

Run doomkit from C++

C++ talks to the library through the same extern "C" API as C — no wrapper layer needed. This example just adds a small Framebuffer class for idiomatic access and uses <chrono>/<thread> for timing.

One C++ gotcha

Callbacks you hand to the C API must be plain functions or non-capturing lambdas. A capturing lambda holds state and cannot be converted to a C function pointer, so it won't compile in dg_callbacks. Keep per-run state in namespace-scope variables (as here) or a singleton.

Build & run

# build libdoomgeneric first — see bindings/README.md
c++ -std=c++17 -I../../../bindings main.cpp -L/path/to/lib -ldoomgeneric -o doomdemo
./doomdemo -iwad /path/to/doom1.wad   # writes frame.ppm at frame 100

On Linux add -Wl,-rpath,/path/to/lib so the loader finds the .so at runtime.

Notes

• dg_screen_buffer() returns uint32_t* to dg_resx()*dg_resy() pixels in 0x00RRGGBB. The Framebuffer class wraps it; read it inside on_draw_frame.
• A real app would blit to a window (SDL/Qt/Win32) instead of saving a PPM, and feed real key events through on_get_key (translate host keys with the same idea as dg_keymap).