#.rst:

# FindOpenGL

# ----------

#

# FindModule for OpenGL and GLU.

#

# Result Variables

# ^^^^^^^^^^^^^^^^

#

# This module sets the following variables:

#

# ``OPENGL_FOUND``

#  True, if the system has OpenGL.

# ``OPENGL_XMESA_FOUND``

#  True, if the system has XMESA.

# ``OPENGL_GLU_FOUND``

#  True, if the system has GLU.

# ``OPENGL_INCLUDE_DIR``

#  Path to the OpenGL include directory.

# ``OPENGL_LIBRARIES``

#  Paths to the OpenGL and GLU libraries.

#

# If you want to use just GL you can use these values:

#

# ``OPENGL_gl_LIBRARY``

#  Path to the OpenGL library.

# ``OPENGL_glu_LIBRARY``

#  Path to the GLU library.

#

# OSX Specific

# ^^^^^^^^^^^^

#

# On OSX default to using the framework version of OpenGL. People will

# have to change the cache values of OPENGL_glu_LIBRARY and

# OPENGL_gl_LIBRARY to use OpenGL with X11 on OSX.

#=============================================================================

# Copyright 2001-2009 Kitware, Inc.

#

# Distributed under the OSI-approved BSD License (the "License");

# see accompanying file Copyright.txt for details.

#

# This software is distributed WITHOUT ANY WARRANTY; without even the

# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

# See the License for more information.

#=============================================================================

# (To distribute this file outside of CMake, substitute the full

#  License text for the above reference.)

set(_OpenGL_REQUIRED_VARS OPENGL_gl_LIBRARY)

if (CYGWIN)

  find_path(OPENGL_INCLUDE_DIR GL/gl.h )

  list(APPEND _OpenGL_REQUIRED_VARS OPENGL_INCLUDE_DIR)

  find_library(OPENGL_gl_LIBRARY opengl32 )

  find_library(OPENGL_glu_LIBRARY glu32 )

elseif (WIN32)

  if(BORLAND)

    set (OPENGL_gl_LIBRARY import32 CACHE STRING "OpenGL library for win32")

    set (OPENGL_glu_LIBRARY import32 CACHE STRING "GLU library for win32")

  else()

    set (OPENGL_gl_LIBRARY opengl32 CACHE STRING "OpenGL library for win32")

    set (OPENGL_glu_LIBRARY glu32 CACHE STRING "GLU library for win32")

  endif()

elseif (APPLE)

  # The OpenGL.framework provides both gl and glu

  find_library(OPENGL_gl_LIBRARY OpenGL DOC "OpenGL library for OS X")

  find_library(OPENGL_glu_LIBRARY OpenGL DOC

    "GLU library for OS X (usually same as OpenGL library)")

  find_path(OPENGL_INCLUDE_DIR OpenGL/gl.h DOC "Include for OpenGL on OS X")

  list(APPEND _OpenGL_REQUIRED_VARS OPENGL_INCLUDE_DIR)

else()

  if (CMAKE_SYSTEM_NAME MATCHES "HP-UX")

    # Handle HP-UX cases where we only want to find OpenGL in either hpux64

    # or hpux32 depending on if we're doing a 64 bit build.

    if(CMAKE_SIZEOF_VOID_P EQUAL 4)

      set(_OPENGL_LIB_PATH

        /opt/graphics/OpenGL/lib/hpux32/)

    else()

      set(_OPENGL_LIB_PATH

        /opt/graphics/OpenGL/lib/hpux64/

        /opt/graphics/OpenGL/lib/pa20_64)

    endif()

  elseif(CMAKE_SYSTEM_NAME STREQUAL Haiku)

    set(_OPENGL_LIB_PATH

      /boot/develop/lib/x86)

    set(_OPENGL_INCLUDE_PATH

      /boot/develop/headers/os/opengl)

  endif()

  # The first line below is to make sure that the proper headers

  # are used on a Linux machine with the NVidia drivers installed.

  # They replace Mesa with NVidia's own library but normally do not

  # install headers and that causes the linking to

  # fail since the compiler finds the Mesa headers but NVidia's library.

  # Make sure the NVIDIA directory comes BEFORE the others.

  #  - Atanas Georgiev <atanas@cs.columbia.edu>

  find_path(OPENGL_INCLUDE_DIR GL/gl.h

    /usr/share/doc/NVIDIA_GLX-1.0/include

    /usr/openwin/share/include

    /opt/graphics/OpenGL/include /usr/X11R6/include

    ${_OPENGL_INCLUDE_PATH}

  )

  list(APPEND _OpenGL_REQUIRED_VARS OPENGL_INCLUDE_DIR)

  find_path(OPENGL_xmesa_INCLUDE_DIR GL/xmesa.h

    /usr/share/doc/NVIDIA_GLX-1.0/include

    /usr/openwin/share/include

    /opt/graphics/OpenGL/include /usr/X11R6/include

  )

  find_library(OPENGL_gl_LIBRARY

    NAMES GL MesaGL

    PATHS /opt/graphics/OpenGL/lib

          /usr/openwin/lib

          /usr/shlib /usr/X11R6/lib

          ${_OPENGL_LIB_PATH}

  )

  unset(_OPENGL_INCLUDE_PATH)

  unset(_OPENGL_LIB_PATH)

  find_library(OPENGL_glu_LIBRARY

    NAMES GLU MesaGLU

    PATHS ${OPENGL_gl_LIBRARY}

          /opt/graphics/OpenGL/lib

          /usr/openwin/lib

          /usr/shlib /usr/X11R6/lib

  )

endif ()

if(OPENGL_gl_LIBRARY)

    if(OPENGL_xmesa_INCLUDE_DIR)

      set( OPENGL_XMESA_FOUND "YES" )

    else()

      set( OPENGL_XMESA_FOUND "NO" )

    endif()

    set( OPENGL_LIBRARIES  ${OPENGL_gl_LIBRARY} ${OPENGL_LIBRARIES})

    if(OPENGL_glu_LIBRARY)

      set( OPENGL_GLU_FOUND "YES" )

      if(NOT "${OPENGL_glu_LIBRARY}" STREQUAL "${OPENGL_gl_LIBRARY}")

        set( OPENGL_LIBRARIES ${OPENGL_glu_LIBRARY} ${OPENGL_LIBRARIES} )

      endif()

    else()

      set( OPENGL_GLU_FOUND "NO" )

    endif()

    # This deprecated setting is for backward compatibility with CMake1.4

    set (OPENGL_LIBRARY ${OPENGL_LIBRARIES})

endif()

# This deprecated setting is for backward compatibility with CMake1.4

set(OPENGL_INCLUDE_PATH ${OPENGL_INCLUDE_DIR})

if(BUILD_ENGINE_JS)

    # The implementation is based on the standard FindOpenGL.cmake provided

    # with CMake, but customized for targeting Emscripten only.

    # These libraries are provided with Emscripten

    SET(OPENGL_FOUND TRUE)

    SET(OPENGL_GLU_FOUND TRUE)

    # Doesn't look like this one is part of Emscripten

    SET(OPENGL_XMESA_FOUND FALSE)

    # This is the path where <GL/gl.h> is found

    SET(OPENGL_INCLUDE_DIR "${EMSCRIPTEN_ROOT_PATH}/system/include")

    # No library to link against for OpenGL, since Emscripten picks it up

    # automatically from library_gl.js, but need to report something, or

    # CMake thinks we failed in the search.

    SET(OPENGL_LIBRARIES "opengl_emscripten_internal")

    SET(OPENGL_gl_LIBRARY "gl_emscripten_internal")

    SET(OPENGL_glu_LIBRARY "glu_emscripten_internal")

    mark_as_advanced(

      OPENGL_INCLUDE_DIR

      OPENGL_glu_LIBRARY

      OPENGL_gl_LIBRARY

    )

endif()

# handle the QUIETLY and REQUIRED arguments and set OPENGL_FOUND to TRUE if

# all listed variables are TRUE

INCLUDE(FindPackageHandleStandardArgs)

FIND_PACKAGE_HANDLE_STANDARD_ARGS(OpenGL REQUIRED_VARS ${_OpenGL_REQUIRED_VARS})

unset(_OpenGL_REQUIRED_VARS)

mark_as_advanced(

  OPENGL_INCLUDE_DIR

  OPENGL_xmesa_INCLUDE_DIR

  OPENGL_glu_LIBRARY

  OPENGL_gl_LIBRARY

)