Dear ImGui outputs 16-bit vertex indices by default. Allegro doesn‘t support them natively, so we have two solutions: convert the indices manually in imgui_impl_allegro5.cpp, or compile dear imgui with 32-bit indices. You can either modify imconfig.h that comes with Dear ImGui (easier), or set a C++ preprocessor option IMGUI_USER_CONFIG to find to a filename. We are providing imconfig_allegro5.h
that enables 32-bit indices. Note that the backend supports BOTH 16-bit and 32-bit indices, but 32-bit indices will be slightly faster as they won’t require a manual conversion.
g++ -DIMGUI_USER_CONFIG=\"examples/example_allegro5/imconfig_allegro5.h\" -I .. -I ../.. main.cpp ../../backends/imgui_impl_allegro5.cpp ../../imgui*.cpp -lallegro -lallegro_main -lallegro_primitives -o allegro5_example
On macOS, install Allegro with homebrew: brew install allegro
.
You may install Allegro using vcpkg:
git clone https://github.com/Microsoft/vcpkg cd vcpkg bootstrap-vcpkg.bat vcpkg install allegro5 --triplet=x86-windows ; for win32 vcpkg install allegro5 --triplet=x64-windows ; for win64 vcpkg integrate install ; register include / libs in Visual Studio
Build:
set ALLEGRODIR=path_to_your_allegro5_folder cl /Zi /MD /I %ALLEGRODIR%\include /DIMGUI_USER_CONFIG=\"examples/example_allegro5/imconfig_allegro5.h\" /I .. /I ..\.. main.cpp ..\..\backends\imgui_impl_allegro5.cpp ..\..\imgui*.cpp /link /LIBPATH:%ALLEGRODIR%\lib allegro-5.0.10-monolith-md.lib user32.lib