cmake_minimum_required(VERSION 3.16)

project(sdlpl LANGUAGES CXX)

Generate compile_commands.json for clangd / neovim (LSP).

set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

--- SWI-Prolog -------------------------------------------------------------

Locate the swipl.cmake helper shipped with SWI-Prolog. The pack manager

sets SWIPL_HOME_DIR for us; for local (non-pack) builds we discover it from

the swipl executable. swipl.cmake then figures out include dirs, linking

requirements and the per-architecture module directory (swipl_module_dir).

if(DEFINED ENV{SWIPL_HOME_DIR}) set(SWIPL_HOME_DIR $ENV{SWIPL_HOME_DIR}) else() find_program(SWIPL_EXECUTABLE swipl REQUIRED) execute_process( COMMAND ${SWIPL_EXECUTABLE} -g "current_prolog_flag(home,H),write(H)" -t halt OUTPUT_VARIABLE SWIPL_HOME_DIR OUTPUT_STRIP_TRAILING_WHITESPACE) endif()

list(INSERT CMAKE_MODULE_PATH 0 ${SWIPL_HOME_DIR}/cmake) include(swipl)

--- SDL3 -------------------------------------------------------------------

find_package(SDL3 REQUIRED) find_package(SDL3_image REQUIRED)

--- Cairo ------------------------------------------------------------------

Cairo ships a pkg-config file but not a CMake config file on most

distributions, so discover it via PkgConfig. pkg_check_modules creates

the cairo::cairo IMPORTED target.

find_package(PkgConfig REQUIRED) pkg_check_modules(CAIRO REQUIRED IMPORTED_TARGET cairo)

--- targets ----------------------------------------------------------------

A MODULE library is loaded dynamically by SWI-Prolog. target_link_swipl

adds the SWI include dirs, links libswipl only when the platform needs it,

and strips the "lib" prefix so the file is sdl.so (not libsdl.so).

Sources live in src/<module>/, one subdirectory per foreign extension.

ptr.h is shared across the sdl and cairo extensions, hence the include

path on both targets.

add_library(sdl MODULE src/sdl/sdl_init.cpp src/sdl/sdl_video.cpp src/sdl/sdl_render.cpp src/sdl/sdl_events.cpp src/sdl/sdl_surface.cpp src/sdl/sdl_image.cpp src/sdl/sdl_gpu.cpp) target_link_swipl(sdl) target_link_libraries(sdl PRIVATE SDL3::SDL3 SDL3_image::SDL3_image) target_include_directories(sdl PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src/ptr)

add_library(ptr MODULE src/ptr/ptr.cpp) target_link_swipl(ptr)

add_library(cairo MODULE src/cairo/cairo.cpp) target_link_swipl(cairo) target_link_libraries(cairo PRIVATE PkgConfig::CAIRO) target_include_directories(cairo PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src/ptr)

Place the shared objects directly into the pack's lib/<arch> directory in the

source tree. This is where use_foreign_library(foreign(sdl)) and

use_foreign_library(foreign(cairo)) load them from and where swipl_add_test()

looks for them. The pack build flow runs tests before install, so the modules

must be present here at build time. The directory is gitignored.

set_target_properties(sdl ptr cairo PROPERTIES LIBRARY_OUTPUT_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/${swipl_module_dir} RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/${swipl_module_dir})

install(TARGETS sdl ptr cairo DESTINATION ${CMAKE_CURRENT_SOURCE_DIR}/${swipl_module_dir})

--- tests ------------------------------------------------------------------

enable_testing() swipl_add_test(sdl)