andrew/libakgl
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity
Files
bcd49fc5b13725b2968316b831ca6d92fe7333cd
libakgl/CMakeLists.txt
Andrew Kesterson bcd49fc5b1 Measure the library: perf suites, a recorded baseline, and targets 
tests/perf.c and tests/perf_render.c drive the hot paths hard enough to
time them -- pool acquire and release at both ends of the scan, the
registry, the state-to-sprite lookup, the per-actor update and render, the
physics sweep, an all-pairs collision sweep, the JSON accessors, path
resolution, the drawing primitives, text, asset loading, a screenful of
tiles, and a whole frame through akgl_game_update. They are registered like
any other suite but carry the `perf` label, so `ctest -L perf` runs only
them and `-LE perf` leaves them out. Every measurement is held to a budget
at roughly ten times the recorded baseline, enforced only in an optimized
build at full scale.

Three things had to be got right before the numbers meant anything, and
each was wrong first:

- No error checking inside the clock. PASS and CATCH call
  akerr_valid_error_address, which walks AKERR_ARRAY_ERROR -- more work than
  several of the calls being measured.
- Flush the renderer before stopping it. SDL batches, so the first version
  measured queueing, reported a tilemap frame 250 times faster than it is,
  and paid the real cost at teardown inside SDL_DestroyTexture.
- A drawing benchmark needs a raw-SDL control doing the same pixel work
  with the same access pattern. With one, akgl_tilemap_draw turns out to
  cost 0.2% of the frame it appeared to own: 16.26 ms against a control's
  16.23 ms for the same 1200 blits. The rasterizer is the frame.

PERFORMANCE.md records the baseline, the frame budget it adds up to, and
what the numbers say -- including that the string pool's acquire is 64x
slower full than empty because it is a megabyte of PATH_MAX buffers, that a
handled missing-sprite condition costs nine times the update it replaces,
that text rasterizes and throws away a texture on every call, and that 28 MB
of the library's BSS is one akgl_Tilemap.

TODO.md gains a Performance section: five defects the stress tests found
that the unit suites do not reach (a tilemap load leaking five pooled
strings, two JSON accessors that turn pool exhaustion into a segfault
rather than AKGL_ERR_HEAP, akgl_game_update crashing without
akgl_game_init, and its actor update sweep running once per tilemap layer),
and eighteen targets with today's number and whether it is met.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 14:24:05 -04:00

410 lines
16 KiB
CMake
Raw Blame History

cmake_minimum_required(VERSION 3.10)
# The single source of truth for the library version. It drives the generated
# include/akgl/version.h, the shared library's VERSION and SOVERSION, and the
# Version field in akgl.pc. Bump it here and nowhere else.
project(akgl VERSION 0.3.0 LANGUAGES C)
include(CTest)
option(AKGL_COVERAGE "Instrument libakgl and generate coverage reports with CTest" OFF)
if(AKGL_COVERAGE)
if(NOT CMAKE_C_COMPILER_ID MATCHES "GNU|Clang")
message(FATAL_ERROR "AKGL_COVERAGE requires GCC or Clang")
endif()
find_program(GCOVR_EXECUTABLE gcovr REQUIRED)
endif()
# Vendored projects own their test suites. Suppress their CTest registration so
# the suite that runs contains only the targets built here. The override is
# lifted again below, before this project registers its own tests, so an
# embedding consumer's add_test() still reaches CTest.
set(AKGL_SUPPRESS_DEPENDENCY_TESTS TRUE)
function(add_test)
if(NOT AKGL_SUPPRESS_DEPENDENCY_TESTS)
_add_test(${ARGV})
endif()
endfunction()
function(set_tests_properties)
if(NOT AKGL_SUPPRESS_DEPENDENCY_TESTS)
_set_tests_properties(${ARGV})
endif()
endfunction()
set(JANSSON_WITHOUT_TESTS ON CACHE BOOL "Do not build vendored Jansson tests" FORCE)
set(JANSSON_EXAMPLES OFF CACHE BOOL "Do not build vendored Jansson examples" FORCE)
set(JANSSON_BUILD_DOCS OFF CACHE BOOL "Do not build vendored Jansson docs" FORCE)
# Add one vendored dependency, if nobody has already declared it and the
# submodule is actually checked out.
#
# A macro rather than a function on purpose: add_subdirectory() inside a
# function runs with that function's variable scope, so every cache-ish variable
# these projects set for their own subdirectories would be discarded on return.
macro(akgl_add_vendored_dependency target dir)
if(NOT TARGET ${target})
if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/${dir}/CMakeLists.txt")
add_subdirectory(${dir} EXCLUDE_FROM_ALL)
set(AKGL_VENDORED_DEPENDENCIES TRUE)
endif()
endif()
endmacro()
# Added on both paths, not just when this is the top-level project. Embedded
# with add_subdirectory(), the submodules under deps/ are sitting right there --
# the recursive clone the consumer just did put them there -- and refusing to
# configure until SDL3 is installed system-wide is a failure with its own answer
# three directories away. if(NOT TARGET ...) means a consumer that has already
# declared one of these wins; the EXISTS check means a checkout without
# submodules falls through to find_package below.
akgl_add_vendored_dependency(jansson::jansson deps/jansson)
akgl_add_vendored_dependency(akerror::akerror deps/libakerror)
akgl_add_vendored_dependency(akstdlib::akstdlib deps/libakstdlib)
akgl_add_vendored_dependency(SDL3::SDL3 deps/SDL)
akgl_add_vendored_dependency(SDL3_image::SDL3_image deps/SDL_image)
akgl_add_vendored_dependency(SDL3_mixer::SDL3_mixer deps/SDL_mixer)
akgl_add_vendored_dependency(SDL3_ttf::SDL3_ttf deps/SDL_ttf)
# libakerror 1.0.0 sizes its own status-name registry; consumers no longer do.
# libakgl claims its status codes at runtime in akgl_heap_init() instead.
set(AKGL_SUPPRESS_DEPENDENCY_TESTS FALSE)
# Anything the vendored block did not supply has to come from the system.
if(NOT (TARGET SDL3::SDL3 AND TARGET SDL3_image::SDL3_image AND
TARGET SDL3_mixer::SDL3_mixer AND TARGET SDL3_ttf::SDL3_ttf AND
TARGET akerror::akerror AND TARGET akstdlib::akstdlib AND
TARGET jansson::jansson))
# Only needed to locate installed copies; a fully vendored build does not
# require pkg-config to be present at all.
find_package(PkgConfig REQUIRED)
endif()
if(NOT TARGET SDL3::SDL3)
find_package(SDL3 REQUIRED)
endif()
if(NOT TARGET SDL3_image::SDL3_image)
find_package(SDL3_image REQUIRED)
endif()
if(NOT TARGET SDL3_mixer::SDL3_mixer)
find_package(SDL3_mixer REQUIRED)
endif()
if(NOT TARGET SDL3_ttf::SDL3_ttf)
find_package(SDL3_ttf REQUIRED)
endif()
# No version here: libakerror ships no akerrorConfigVersion.cmake, so asking
# for one makes find_package reject every install. The floor is enforced by
# the #error in include/akgl/error.h instead, which feature-tests
# AKERR_FIRST_CONSUMER_STATUS.
if(NOT TARGET akerror::akerror)
find_package(akerror REQUIRED)
endif()
# 0.2 rather than bare: libakstdlib 0.2.0 ships an akstdlibConfigVersion.cmake
# with SameMinorVersion compatibility, mirroring its soname, so this accepts
# any 0.2.x and refuses 0.3 and 1.0. Unversioned, this path would silently
# accept an ABI-incompatible libakstdlib.
if(NOT TARGET akstdlib::akstdlib)
find_package(akstdlib 0.2 REQUIRED)
endif()
if(NOT TARGET jansson::jansson)
find_package(jansson)
endif()
set(GAMECONTROLLERDB_H "include/akgl/SDL_GameControllerDB.h")
set(prefix ${CMAKE_INSTALL_PREFIX})
set(exec_prefix "\${prefix}")
set(libdir "\${exec_prefix}/lib")
set(includedir "\${prefix}/include")
configure_file(${CMAKE_CURRENT_SOURCE_DIR}/akgl.pc.in ${CMAKE_CURRENT_BINARY_DIR}/akgl.pc @ONLY)
configure_file(${CMAKE_CURRENT_SOURCE_DIR}/include/akgl/version.h.in
${CMAKE_CURRENT_BINARY_DIR}/include/akgl/version.h @ONLY)
# Tests use both relative paths and SDL_GetBasePath(), so stage fixtures beside
# test executables in every out-of-tree build.
file(COPY "${CMAKE_CURRENT_SOURCE_DIR}/tests/assets"
DESTINATION "${CMAKE_CURRENT_BINARY_DIR}")
add_custom_command(
OUTPUT ${GAMECONTROLLERDB_H}
COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/mkcontrollermappings.sh ${CMAKE_CURRENT_SOURCE_DIR}
COMMENT "Generating controller mappings ..."
)
# Add include directories
include_directories(${SDL3_INCLUDE_DIRS})
add_library(akgl SHARED
deps/semver/semver.c
src/actor.c
src/actor_state_string_names.c
src/audio.c
src/text.c
src/assets.c
src/character.c
src/draw.c
src/error.c
src/game.c
src/controller.c
src/heap.c
src/json_helpers.c
src/registry.c
src/renderer.c
src/physics.c
src/sprite.c
src/staticstring.c
src/tilemap.c
src/util.c
src/version.c
${GAMECONTROLLERDB_H}
)
# While the major version is 0 the ABI is not stable across minor releases, so
# the soname carries major.minor -- libakgl.so.0.1. A plain SOVERSION 0 would
# claim 0.1.0 and 0.2.0 are interchangeable, which is exactly the silent
# mispairing the soname is here to prevent. At 1.0.0 this becomes the major
# alone, matching libakerror.
if(PROJECT_VERSION_MAJOR EQUAL 0)
set(AKGL_SOVERSION "${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}")
else()
set(AKGL_SOVERSION "${PROJECT_VERSION_MAJOR}")
endif()
set_target_properties(akgl PROPERTIES
VERSION ${PROJECT_VERSION}
SOVERSION ${AKGL_SOVERSION}
)
add_library(akgl::akgl ALIAS akgl)
add_executable(charviewer util/charviewer.c)
add_executable(akgl_test_semver_unit deps/semver/semver_unit.c)
# Every suite here is a standalone C program named tests/<name>.c, built as
# akgl_test_<name> and registered with CTest under <name>.
set(AKGL_TEST_SUITES
actor
audio
bitmasks
character
controller
draw
error
game
headers
heap
json_helpers
physics
registry
renderer
sprite
staticstring
text
tilemap
util
version
)
# The performance suites are built and registered exactly like the unit suites,
# but they are benchmarks: they drive hot paths for millions of iterations, print
# a table of nanoseconds per operation, and fail only when a measurement exceeds
# a budget set at roughly ten times the recorded baseline. They carry the `perf`
# label, so `ctest -L perf` runs only them and `ctest -LE perf` leaves them out
# of an ordinary run, and they get a much longer timeout for obvious reasons.
#
# Set AKGL_BENCH_SCALE in the environment to change how long they run --
# `AKGL_BENCH_SCALE=0.1 ctest -L perf` for a tenth of the iterations. Below 1.0
# the budgets are measured and reported but not enforced, because a short run is
# a noisy one.
set(AKGL_PERF_SUITES
perf
perf_render
)
# The executables carry an akgl_ prefix but the CTest names do not: a vendored
# dependency is free to ship its own tests/version.c, and libakstdlib now does.
# Its target is created by add_subdirectory even though EXCLUDE_FROM_ALL keeps
# it from being built, so an unprefixed test_version here is a configure error.
foreach(suite IN LISTS AKGL_TEST_SUITES AKGL_PERF_SUITES)
add_executable(akgl_test_${suite} tests/${suite}.c)
add_test(NAME ${suite} COMMAND akgl_test_${suite})
endforeach()
add_test(NAME semver_unit COMMAND akgl_test_semver_unit)
set_tests_properties(
${AKGL_TEST_SUITES} semver_unit
PROPERTIES WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/tests" TIMEOUT 30
)
set_tests_properties(
${AKGL_PERF_SUITES}
PROPERTIES
WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/tests"
TIMEOUT 900
LABELS perf
)
# Specify include directories for the library's headers (if applicable)
target_include_directories(akgl PUBLIC
include/
deps/semver/
# akgl/version.h is generated by configure_file, so it lives in the build tree
# rather than beside the headers it is included from.
${CMAKE_CURRENT_BINARY_DIR}/include/
)
if(AKGL_COVERAGE)
target_compile_options(akgl PRIVATE --coverage -O0 -g)
target_link_options(akgl PRIVATE --coverage)
set(AKGL_COVERAGE_DIR "${CMAKE_CURRENT_BINARY_DIR}/coverage")
file(MAKE_DIRECTORY "${AKGL_COVERAGE_DIR}")
add_test(
NAME coverage_reset
COMMAND ${GCOVR_EXECUTABLE}
--root "${CMAKE_CURRENT_SOURCE_DIR}"
--object-directory "${CMAKE_CURRENT_BINARY_DIR}"
--delete
)
set_tests_properties(coverage_reset PROPERTIES FIXTURES_SETUP akgl_coverage)
# Any suite missing from this list runs outside the fixture and has its
# counters discarded by coverage_reset. The perf suites are deliberately
# outside it: an instrumented -O0 build measures gcov, not libakgl, and the
# lines they cover are covered by the unit suites anyway.
set_tests_properties(
${AKGL_TEST_SUITES} semver_unit
PROPERTIES FIXTURES_REQUIRED akgl_coverage
)
add_test(
NAME coverage_report
COMMAND ${GCOVR_EXECUTABLE}
--root "${CMAKE_CURRENT_SOURCE_DIR}"
--object-directory "${CMAKE_CURRENT_BINARY_DIR}"
--filter "${CMAKE_CURRENT_SOURCE_DIR}/src/"
--xml-pretty
--xml "${AKGL_COVERAGE_DIR}/coverage.xml"
--html-details "${AKGL_COVERAGE_DIR}/index.html"
)
set_tests_properties(
coverage_report
PROPERTIES
FIXTURES_CLEANUP akgl_coverage
WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
)
endif()
target_link_libraries(akgl
PUBLIC
SDL3::SDL3
SDL3_image::SDL3_image
SDL3_mixer::SDL3_mixer
SDL3_ttf::SDL3_ttf
akstdlib::akstdlib
akerror::akerror
jansson::jansson
)
foreach(suite IN LISTS AKGL_TEST_SUITES AKGL_PERF_SUITES)
target_link_libraries(akgl_test_${suite} PRIVATE akstdlib::akstdlib akerror::akerror akgl SDL3::SDL3 SDL3_ttf::SDL3_ttf SDL3_image::SDL3_image SDL3_mixer::SDL3_mixer jansson::jansson -lm)
target_include_directories(akgl_test_${suite} PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/tests")
endforeach()
target_link_libraries(charviewer PRIVATE akstdlib::akstdlib akerror::akerror akgl SDL3::SDL3 SDL3_ttf::SDL3_ttf SDL3_image::SDL3_image SDL3_mixer::SDL3_mixer jansson::jansson -lm)
# When the vendored SDL satellite libraries are built in-tree they land in per-
# project subdirectories that are not on the loader's default search path, so a
# freshly built test aborts before main() with "cannot open shared object file".
# Bake those directories into the build-tree RPATH. Installed builds resolve the
# same libraries through find_package and need no help, so this keys on whether
# anything was actually vendored rather than on being the top-level project.
if(AKGL_VENDORED_DEPENDENCIES)
set(AKGL_VENDORED_RPATH
"$<TARGET_FILE_DIR:SDL3::SDL3>"
"$<TARGET_FILE_DIR:SDL3_image::SDL3_image>"
"$<TARGET_FILE_DIR:SDL3_ttf::SDL3_ttf>"
"$<TARGET_FILE_DIR:SDL3_mixer::SDL3_mixer>"
"$<TARGET_FILE_DIR:akerror::akerror>"
"$<TARGET_FILE_DIR:akstdlib::akstdlib>"
)
foreach(suite IN LISTS AKGL_TEST_SUITES AKGL_PERF_SUITES)
set_target_properties(akgl_test_${suite} PROPERTIES BUILD_RPATH "${AKGL_VENDORED_RPATH}")
endforeach()
set_target_properties(charviewer akgl PROPERTIES BUILD_RPATH "${AKGL_VENDORED_RPATH}")
# RPATH alone is not enough: LD_LIBRARY_PATH is searched first, so a developer
# who has previously run rebuild.sh has an installed libakgl.so ahead of the
# one under test. Prepend the build tree for the CTest run so the suite always
# exercises what was just compiled.
set(AKGL_TEST_LIBPATH
"${CMAKE_CURRENT_BINARY_DIR}"
"${CMAKE_CURRENT_BINARY_DIR}/deps/SDL"
"${CMAKE_CURRENT_BINARY_DIR}/deps/SDL_image"
"${CMAKE_CURRENT_BINARY_DIR}/deps/SDL_ttf"
"${CMAKE_CURRENT_BINARY_DIR}/deps/SDL_mixer"
"${CMAKE_CURRENT_BINARY_DIR}/deps/libakerror"
"${CMAKE_CURRENT_BINARY_DIR}/deps/libakstdlib"
)
if(CMAKE_VERSION VERSION_GREATER_EQUAL "3.22")
set(AKGL_TEST_ENV_MOD "")
foreach(dir IN LISTS AKGL_TEST_LIBPATH)
list(APPEND AKGL_TEST_ENV_MOD "LD_LIBRARY_PATH=path_list_prepend:${dir}")
endforeach()
set_tests_properties(
${AKGL_TEST_SUITES} ${AKGL_PERF_SUITES}
PROPERTIES ENVIRONMENT_MODIFICATION "${AKGL_TEST_ENV_MOD}"
)
else()
string(REPLACE ";" ":" AKGL_TEST_LIBPATH_JOINED "${AKGL_TEST_LIBPATH}")
set_tests_properties(
${AKGL_TEST_SUITES} ${AKGL_PERF_SUITES}
PROPERTIES ENVIRONMENT "LD_LIBRARY_PATH=${AKGL_TEST_LIBPATH_JOINED}:$ENV{LD_LIBRARY_PATH}"
)
endif()
endif()
# Mutation testing copies the repository to scratch space, applies one small
# source change at a time, and verifies that the passing tests detect it. The
# intentionally failing character test is excluded by the harness.
find_package(Python3 COMPONENTS Interpreter)
if(Python3_FOUND)
if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
set(AKGL_MUTATION_TARGET mutation)
else()
set(AKGL_MUTATION_TARGET akgl_mutation)
endif()
add_custom_target(${AKGL_MUTATION_TARGET}
COMMAND ${Python3_EXECUTABLE}
${CMAKE_CURRENT_SOURCE_DIR}/scripts/mutation_test.py
--source-root ${CMAKE_CURRENT_SOURCE_DIR}
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
USES_TERMINAL
COMMENT "Running mutation tests (breaks a scratch copy, expects tests to fail)"
)
endif()
install(FILES ${CMAKE_CURRENT_BINARY_DIR}/akgl.pc DESTINATION "lib/pkgconfig/")
install(FILES ${CMAKE_CURRENT_BINARY_DIR}/include/akgl/version.h DESTINATION "include/akgl/")
install(TARGETS akgl DESTINATION "lib/")
install(FILES "deps/semver/semver.h" DESTINATION "include/")
install(FILES "include/akgl/actor.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/types.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/text.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/assets.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/audio.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/character.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/error.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/draw.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/game.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/controller.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/heap.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/iterator.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/json_helpers.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/renderer.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/physics.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/registry.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/sprite.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/staticstring.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/tilemap.h" DESTINATION "include/akgl/")
install(FILES "include/akgl/util.h" DESTINATION "include/akgl/")
install(FILES ${GAMECONTROLLERDB_H} DESTINATION "include/akgl/")
Reference in New Issue View Git Blame Copy Permalink