# - Find OpenSubdiv library
# Find the native OpenSubdiv includes and library
# This module defines
#  OPENSUBDIV_INCLUDE_DIRS, where to find OpenSubdiv headers, Set when
#                           OPENSUBDIV_INCLUDE_DIR is found.
#  OPENSUBDIV_LIBRARIES, libraries to link against to use OpenSubdiv.
#  OPENSUBDIV_ROOT_DIR, the base directory to search for OpenSubdiv.
#                        This can also be an environment variable.
#  OPENSUBDIV_FOUND, if false, do not try to use OpenSubdiv.
#
# also defined, but not for general use are
#  OPENSUBDIV_LIBRARY, where to find the OpenSubdiv library.

#=============================================================================
# Copyright 2013 Blender Foundation.
#
# 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.
#=============================================================================

# If OPENSUBDIV_ROOT_DIR was defined in the environment, use it.
IF(NOT OPENSUBDIV_ROOT_DIR AND NOT $ENV{OPENSUBDIV_ROOT_DIR} STREQUAL "")
    SET(OPENSUBDIV_ROOT_DIR $ENV{OPENSUBDIV_ROOT_DIR})
ENDIF()

SET(_opensubdiv_FIND_COMPONENTS
    osdCPU
)
if(OPENSUBDIV_USE_GPU)
    list(APPEND
        _opensubdiv_FIND_COMPONENTS
        osdGPU)
endif()


SET(_opensubdiv_SEARCH_DIRS
    ${OPENSUBDIV_ROOT_DIR}
    /usr/local
    /sw # Fink
    /opt/local # DarwinPorts
    /opt/csw # Blastwave
    /opt/lib/opensubdiv
    /opt/lib/osd # install_deps.sh
)

FIND_PATH(OPENSUBDIV_INCLUDE_DIR
    NAMES
        opensubdiv/osd/mesh.h
    HINTS
        ${_opensubdiv_SEARCH_DIRS}
    PATH_SUFFIXES
        include
)

if(OPENSUBDIV_INCLUDE_DIR AND EXISTS "${OPENSUBDIV_INCLUDE_DIR}/opensubdiv/version.h")
    file(STRINGS
         ${OPENSUBDIV_INCLUDE_DIR}/opensubdiv/version.h
         TMP
         REGEX "#define OPENSUBDIV_VERSION v.*$"
    )
    string(REGEX
        MATCHALL "[0-9]_[0-9]_[0-9]"
        OPENSUBDIV_VERSION
        ${TMP}
    )
    string(REPLACE
        "_"
        "."
        OPENSUBDIV_VERSION
        ${OPENSUBDIV_VERSION}
    )
endif()

SET(_opensubdiv_LIBRARIES)
FOREACH(COMPONENT ${_opensubdiv_FIND_COMPONENTS})
  STRING(TOUPPER ${COMPONENT} UPPERCOMPONENT)
  FIND_LIBRARY(OPENSUBDIV_${UPPERCOMPONENT}_LIBRARY
    NAMES
      ${COMPONENT}
    HINTS
      ${_opensubdiv_SEARCH_DIRS}
    PATH_SUFFIXES
      lib64 lib
    )
  if(DEFINED OPENSUBDIV_${UPPERCOMPONENT}_LIBRARY)
    LIST(APPEND
        _opensubdiv_LIBRARIES
        "${OPENSUBDIV_${UPPERCOMPONENT}_LIBRARY}")
    set(OPENSUBDIV_FOUND TRUE)
  endif()
ENDFOREACH()

MACRO(OPENSUBDIV_CHECK_CONTROLLER
      controller_include_file
      variable_name)
  IF(EXISTS
    "${OPENSUBDIV_INCLUDE_DIR}/opensubdiv/osd/${controller_include_file}"
    )
    SET(${variable_name} TRUE)
  ELSE()
    SET(${variable_name} FALSE)
  ENDIF()
ENDMACRO()


IF(OPENSUBDIV_FOUND)
  SET(OPENSUBDIV_LIBRARIES ${_opensubdiv_LIBRARIES})
  SET(OPENSUBDIV_INCLUDE_DIRS ${OPENSUBDIV_INCLUDE_DIR})

  # Find available compute controllers that USD may want to use.
  OPENSUBDIV_CHECK_CONTROLLER("glXFBEvaluator.h" OPENSUBDIV_HAS_GLSL_TRANSFORM_FEEDBACK)
  OPENSUBDIV_CHECK_CONTROLLER("glComputeEvaluator.h" OPENSUBDIV_HAS_GLSL_COMPUTE)
ENDIF(OPENSUBDIV_FOUND)

MARK_AS_ADVANCED(
  OPENSUBDIV_INCLUDE_DIR
)
FOREACH(COMPONENT ${_opensubdiv_FIND_COMPONENTS})
  STRING(TOUPPER ${COMPONENT} UPPERCOMPONENT)
  MARK_AS_ADVANCED(OPENSUBDIV_${UPPERCOMPONENT}_LIBRARY)
ENDFOREACH()

# handle the QUIETLY and REQUIRED arguments and set OPENSUBDIV_FOUND to TRUE if
# all listed variables are TRUE
INCLUDE(FindPackageHandleStandardArgs)
FIND_PACKAGE_HANDLE_STANDARD_ARGS(OpenSubdiv
    REQUIRED_VARS
        OPENSUBDIV_INCLUDE_DIR
        OPENSUBDIV_LIBRARIES
    VERSION_VAR
        OPENSUBDIV_VERSION
)