project raytracer

# Settable from the command line, for example: meowc -D samples=128 build
option samples  string 48
option threads  bool   true
option with_png bool   true
option fast     bool   false

set warnings -Wall -Wextra -Wpedantic -Wshadow
set posix    -D_POSIX_C_SOURCE=200809L

toolchain {
  cc       cc
  cxx      c++
  cflags   ${warnings} ${posix} -std=c17
  cxxflags ${warnings} -std=c++17
}

if fast {
  toolchain {
    cflags   -O3 -march=native
    cxxflags -O3 -march=native
  }
} else {
  toolchain {
    cflags   -O2
    cxxflags -O2
  }
}

# Feature detection runs in written order, so the conditionals below see it.
check header stdio.h
check header pthread.h
check func   sqrt in m
check func   clock_gettime
check symbol CLOCK_MONOTONIC in time.h
check sizeof void*
check compiles c11_atomics "#include <stdatomic.h>\nint main(void){ atomic_int a = 0; return atomic_load(&a); }"

if threads and have_pthread_h {
  check func pthread_create in pthread
}

if with_png {
  pkg zlib
}

if not have_zlib {
  message warn "building without zlib, so renders will be written as PPM"
}

config_header include/rt_config.h

# Every .scene file becomes a C translation unit and a header.
rule scenes {
  inputs      scenes/*.scene
  outputs     gen/${stem}_scene.c gen/${stem}_scene.h
  command     tools/scenegen.py ${in} ${out0} ${out1}
  description ${stem}_scene.c
}

lib rtmath {
  srcs    src/math/*.c
  include include
  ldflags -lm
}

lib rtscene {
  srcs    src/scene/*.c gen/*_scene.c
  include include gen
  use     rtmath
  if have_pthread_create {
    ldflags -lpthread
  }
}

lib rtimage {
  srcs    src/image/*.c
  include include
  use     rtmath
  if have_zlib {
    pkg zlib
  }
}

# The same sources again as one position independent library.
shared rt {
  srcs    src/math/*.c src/scene/*.c src/image/*.c gen/*_scene.c
  include include gen
  soname  librt.so.1
  ldflags -lm
  install lib
  if have_zlib {
    pkg zlib
  }
  if have_pthread_create {
    ldflags -lpthread
  }
}

bin render {
  srcs    src/main.c
  include include gen
  use     rtscene rtimage
  define  RT_DEFAULT_SAMPLES=${samples}
  define  RT_COMPILER="${cc_id}"
  install bin
}

bin rtbench {
  srcs    src/bench.cpp
  include include gen
  use     rtscene
}

# A canned invocation, for a quick low sample preview. ${builddir} follows the
# target triple, so this still points at the right binary under --target.
run preview {
  use     render
  command ${builddir}/bin/render --scene rings --width 320 --height 180 --samples 8
}

test math_test {
  srcs    tests/math_test.c
  include include
  use     rtmath
}

test scene_test {
  srcs    tests/scene_test.c
  include include gen
  use     rtscene
}

test image_test {
  srcs    tests/image_test.c
  include include
  use     rtimage
}

install headers {
  files include/rt.h include/rt_scene.h include/rt_image.h
  to    include
}