cmake_minimum_required(VERSION 3.0.2)

project(openvr_samples)

# -----------------------------------------------------------------------------
## SYSTEM PROPERTIES ##

# If not set, determines the running platform architecture.
if(NOT PLATFORM)
  if(CMAKE_SIZEOF_VOID_P MATCHES 8)
    set(PLATFORM 64)
  else()
    set(PLATFORM 32)
  endif()
endif()
message(STATUS "Compilation set for ${PLATFORM}bits architectures.")

set(SDL_REQUIRED_LIBRARIES SDL2)

if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
  add_definitions(-DLINUX -DPOSIX)
  set(ARCH_TARGET linux64)

  if(${PLATFORM} MATCHES 32)
    message(WARNING "OpenVR x86 binaries not provided on GNU/Linux.")
  endif()
elseif(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
  set(CMAKE_MACOSX_RPATH 0)
  add_definitions(-DOSX -DPOSIX)
  set(ARCH_TARGET osx32)

elseif(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
  set(SDL_REQUIRED_LIBRARIES ${SDL_REQUIRED_LIBRARIES} SDL2main)
  add_definitions(-D_WIN32)
  set(ARCH_TARGET win${PLATFORM})

  # Binaries path for thirdparties are not generics so we try to guess their suffixes.
  set(WINDOWS_PATH_SUFFIXES win${PLATFORM} Win${PLATFORM} x${PLATFORM})

  if(${PLATFORM} MATCHES 64)
    message(WARNING "SDL x64 runtime binaries not provided on Windows.")
  endif()
endif()

# -----------------------------------------------------------------------------
## PATHS ##

set(THIRDPARTY_DIR ${CMAKE_CURRENT_SOURCE_DIR}/thirdparty)
set(SHARED_SRC_DIR ${CMAKE_CURRENT_SOURCE_DIR}/shared)

# Check that the steamVR SDK is installed 
# (needed to prevent a segfault in OpenVR).
if(CMAKE_HOST_UNIX)
  find_file(OPENVRPATHS openvrpaths.vrpath PATHS $ENV{HOME}/.config/openvr "$ENV{HOME}/Library/Application Support/OpenVR/.openvr")
  if(${OPENVRPATHS} MATCHES OPENVRPATHS-NOTFOUND)
    message(FATAL_ERROR "${OPENVRPATHS} Please install SteamVR SDK to continue..")
  endif()
endif()

# Default output directory.
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bin/${ARCH_TARGET})
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bin/${ARCH_TARGET})
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/bin/${ARCH_TARGET})

# Force output directory destination, especially for MSVC (@so7747857).
function(setTargetOutputDirectory target)
  foreach(type RUNTIME LIBRARY ARCHIVE)
    set_target_properties(${target} PROPERTIES
      ${type}_OUTPUT_DIRECTORY         ${CMAKE_${type}_OUTPUT_DIRECTORY}
      ${type}_OUTPUT_DIRECTORY_DEBUG   ${CMAKE_${type}_OUTPUT_DIRECTORY}
      ${type}_OUTPUT_DIRECTORY_RELEASE ${CMAKE_${type}_OUTPUT_DIRECTORY}
    )
  endforeach()
endfunction()

# -----------------------------------------------------------------------------
## COMPILER DETECTION ##
if(   (${CMAKE_CXX_COMPILER_ID} MATCHES "GNU")
   OR (${CMAKE_CXX_COMPILER_ID} MATCHES "Clang"))
  # Better to use the prebuilt GNU preprocessor define __GNUC__,
  # kept for legacy reason with the sample code.
  add_definitions(-DGNUC)

  set(CMAKE_CXX_FLAGS         "${CMAKE_CXX_FLAGS} -std=c++11 -include ${SHARED_SRC_DIR}/compat.h")
  set(CMAKE_CXX_FLAGS_DEBUG   "${CMAKE_CXX_FLAGS_DEBUG} -Wall -Wextra -pedantic -g")
  set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O2")

  # Handles x86 compilation support on x64 arch.
  if(${PLATFORM} MATCHES 32)
    set(CMAKE_CXX_FLAGS        "${CMAKE_CXX_FLAGS} -m32")
    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
  endif()
elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
  set(CMAKE_CXX_FLAGS_DEBUG   "${CMAKE_CXX_FLAGS_DEBUG} /W2 /DEBUG")
  set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /MP /INCREMENTAL:NO")
else()
  message(FATAL_ERROR "Unsupported compiler '${CMAKE_CXX_COMPILER_ID}'")
endif()

# -----------------------------------------------------------------------------
## LIBRARIES ##

## OpenGL / GLU
find_package(OpenGL REQUIRED)

## GLEW 1.11
if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
  # On GNU/Linux, glew can be found on the package manager. 
  find_package(GLEW 1.11 REQUIRED)
else()
  # Otherwise, use the shipped binaries.
  find_library(GLEW_LIBRARIES
    NAMES
      GLEW
      glew32
    PATHS
      ${THIRDPARTY_DIR}/glew/glew-1.11.0/lib/Release
    PATH_SUFFIXES
      osx32
      ${WINDOWS_PATH_SUFFIXES}
  )
  set(GLEW_INCLUDE_DIR ${THIRDPARTY_DIR}/glew/glew-1.11.0/include)
endif()

## SDL 2
## osx32 and linux32 cmake can spot each others' .so and .a files, so keep them apart
if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
  foreach(lib ${SDL_REQUIRED_LIBRARIES})
    find_library(${lib}_LIBRARY
      NAMES
        ${lib}
      PATHS
        ${THIRDPARTY_DIR}/sdl2-2.0.3/bin
      PATH_SUFFIXES
        osx32
    )
    list(APPEND SDL2_LIBRARIES ${${lib}_LIBRARY})
  endforeach()
else()
  foreach(lib ${SDL_REQUIRED_LIBRARIES})
    find_library(${lib}_LIBRARY
      NAMES
        ${lib}
      PATHS
        ${THIRDPARTY_DIR}/sdl2-2.0.3/bin
      PATH_SUFFIXES
        linux${PLATFORM}
        ${WINDOWS_PATH_SUFFIXES}
    )
    list(APPEND SDL2_LIBRARIES ${${lib}_LIBRARY})
  endforeach()
endif()
set(SDL2_INCLUDE_DIR ${THIRDPARTY_DIR}/sdl2-2.0.3/include)

## Vulkan
if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin"))
  find_library(VULKAN_LIBRARY
      NAMES
        vulkan-1
        vulkan
      PATHS
        ${THIRDPARTY_DIR}/vulkan-1.0.49.0/lib
      PATH_SUFFIXES
        linux${PLATFORM}
        ${WINDOWS_PATH_SUFFIXES}
      NO_DEFAULT_PATH
  )
  set(VULKAN_INCLUDE_DIR ${THIRDPARTY_DIR}/vulkan-1.0.49.0/include)
endif()


## Qt 5
## Important :
## Remember to set CMAKE_PREFIX_PATH to Qt5 cmake modules path for your targeted platform
## or set them here manually (not portable).
# if(CMAKE_HOST_UNIX)
#   list(APPEND CMAKE_PREFIX_PATH "/opt/Qt/5.6/gcc_64/lib/cmake")
# else()
#     if(${PLATFORM} MATCHES 64)
#       set(suffix "_64")
#     endif
#   list(APPEND CMAKE_PREFIX_PATH "C:/Qt/5.6/msvc2013${suffix}/lib/cmake")
# endif()

# Set CMake to run moc automatically has needed.
set(CMAKE_AUTOMOC ON)
# Set CMake to handle *.ui generation to avoid using QT5_WRAP_UI() macro.
set(CMAKE_AUTOUIC ON)
# Add the build dir to include paths to find UI's headers.
set(CMAKE_INCLUDE_CURRENT_DIR ON)

# Find Qt5 libraries.
foreach(module Core Gui Widgets)
    find_package(Qt5 REQUIRED COMPONENTS ${module})
    list(APPEND QT_INCLUDE_DIRS "${Qt5${module}_INCLUDE_DIRS}")
    list(APPEND QT_LIBRARIES    "${Qt5${module}_LIBRARIES}")
    list(APPEND QT_FLAGS        "${Qt5${module}_EXECUTABLE_COMPILE_FLAGS}")
    list(APPEND QT_DEFINITIONS  "${Qt5${module}_DEFINITIONS}")
endforeach()
# Correct QT_FLAGS having semicolons, which break the compile step on POSIX
list(REMOVE_DUPLICATES QT_FLAGS)

## OpenVR API path
find_library(OPENVR_LIBRARIES
  NAMES
    openvr_api
  PATHS
    ${CMAKE_CURRENT_SOURCE_DIR}/../bin
    ${CMAKE_CURRENT_SOURCE_DIR}/../lib
  PATH_SUFFIXES
    osx32
    linux64
    ${WINDOWS_PATH_SUFFIXES}
  NO_DEFAULT_PATH
  NO_CMAKE_FIND_ROOT_PATH
)
set(OPENVR_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../headers)


# -----------------------------------------------------------------------------
## SHARED SOURCES ##

file(GLOB SHARED_SRC_FILES
  ${SHARED_SRC_DIR}/*.cpp
  ${SHARED_SRC_DIR}/*.h
)

include_directories(
  .
  ${OPENGL_INCLUDE_DIR}
  ${GLEW_INCLUDE_DIR}
  ${SDL2_INCLUDE_DIR}
  ${QT_INCLUDE_DIRS}
  ${OPENVR_INCLUDE_DIR}
)

if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin"))
  include_directories(${VULKAN_INCLUDE_DIR})
endif()

# -----------------------------------------------------------------------------
## SUBDIRECTORIES ##

add_subdirectory(hellovr_opengl)
if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin"))
  add_subdirectory(hellovr_vulkan)
endif()
add_subdirectory(helloworldoverlay)
add_subdirectory(tracked_camera_openvr_sample)

# -----------------------------------------------------------------------------