cmake: update FindSDL2_ttf.cmake

Pull it from https://github.com/aminosbh/sdl2-cmake-modules, which
seems to be a slightly newer version and with an explicit license
statement.

Also switch to one of the better variables for SDL2_ttf:
- SDL2_TTF_INCLUDE_DIR -> SDL2_TTF_INCLUDE_DIRS

cmake/FindSDL2_ttf.cmake

@@ -1,98 +1,222 @@
-# Locate SDL_ttf library
-#
-# This module defines:
-#
-# ::
-#
-#   SDL2_TTF_LIBRARIES, the name of the library to link against
-#   SDL2_TTF_INCLUDE_DIRS, where to find the headers
-#   SDL2_TTF_FOUND, if false, do not try to link against
-#   SDL2_TTF_VERSION_STRING - human-readable string containing the version of SDL_ttf
-#
-#
-#
-# For backward compatibility the following variables are also set:
-#
-# ::
-#
-#   SDLTTF_LIBRARY (same value as SDL2_TTF_LIBRARIES)
-#   SDLTTF_INCLUDE_DIR (same value as SDL2_TTF_INCLUDE_DIRS)
-#   SDLTTF_FOUND (same value as SDL2_TTF_FOUND)
-#
-#
-#
-# $SDLDIR is an environment variable that would correspond to the
-# ./configure --prefix=$SDLDIR used in building SDL.
-#
-# Created by Eric Wing.  This was influenced by the FindSDL.cmake
-# module, but with modifications to recognize OS X frameworks and
-# additional Unix paths (FreeBSD, etc).
-
-#=============================================================================
-# Copyright 2005-2009 Kitware, Inc.
-# Copyright 2012 Benjamin Eikel
-#
-# 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.)
+# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
 
+#  Copyright 2019 Amine Ben Hassouna <[email protected]>
+#  Copyright 2000-2019 Kitware, Inc. and Contributors
+#  All rights reserved.
+
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions
+#  are met:
+
+#  * Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+
+#  * Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+
+#  * Neither the name of Kitware, Inc. nor the names of Contributors
+#    may be used to endorse or promote products derived from this
+#    software without specific prior written permission.
+
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#  HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#[=======================================================================[.rst:
+FindSDL2_ttf
+------------
+
+Locate SDL2_ttf library
+
+This module defines the following 'IMPORTED' target:
+
+::
+
+  SDL2::TTF
+    The SDL2_ttf library, if found.
+    Have SDL2::Core as a link dependency.
+
+
+
+This module will set the following variables in your project:
+
+::
+
+  SDL2_TTF_LIBRARIES, the name of the library to link against
+  SDL2_TTF_INCLUDE_DIRS, where to find the headers
+  SDL2_TTF_FOUND, if false, do not try to link against
+  SDL2_TTF_VERSION_STRING - human-readable string containing the
+                            version of SDL2_ttf
+
+
+
+This module responds to the following cache variables:
+
+::
+
+  SDL2_TTF_PATH
+    Set a custom SDL2_ttf Library path (default: empty)
+
+  SDL2_TTF_NO_DEFAULT_PATH
+    Disable search SDL2_ttf Library in default path.
+      If SDL2_TTF_PATH (default: ON)
+      Else (default: OFF)
+
+  SDL2_TTF_INCLUDE_DIR
+    SDL2_ttf headers path.
+
+  SDL2_TTF_LIBRARY
+    SDL2_ttf Library (.dll, .so, .a, etc) path.
+
+
+Additional Note: If you see an empty SDL2_TTF_LIBRARY in your project
+configuration, it means CMake did not find your SDL2_ttf library
+(SDL2_ttf.dll, libsdl2_ttf.so, etc). Set SDL2_TTF_LIBRARY to point
+to your SDL2_ttf library, and  configure again. This value is used to
+generate the final SDL2_TTF_LIBRARIES variable and the SDL2::TTF target,
+but when this value is unset, SDL2_TTF_LIBRARIES and SDL2::TTF does not
+get created.
+
+
+$SDL2TTFDIR is an environment variable that would correspond to the
+./configure --prefix=$SDL2TTFDIR used in building SDL2_ttf.
+
+$SDL2DIR is an environment variable that would correspond to the
+./configure --prefix=$SDL2DIR used in building SDL2.
+
+
+
+Created by Amine Ben Hassouna:
+  Adapt FindSDL_ttf.cmake to SDL2_ttf (FindSDL2_ttf.cmake).
+  Add cache variables for more flexibility:
+    SDL2_TTF_PATH, SDL2_TTF_NO_DEFAULT_PATH (for details, see doc above).
+  Add SDL2 as a required dependency.
+  Modernize the FindSDL2_ttf.cmake module by creating a specific target:
+    SDL2::TTF (for details, see doc above).
+
+Original FindSDL_ttf.cmake module:
+  Created by Eric Wing.  This was influenced by the FindSDL.cmake
+  module, but with modifications to recognize OS X frameworks and
+  additional Unix paths (FreeBSD, etc).
+#]=======================================================================]
+
+# SDL2 Library required
+find_package(SDL2 QUIET)
+if(NOT SDL2_FOUND)
+  set(SDL2_TTF_SDL2_NOT_FOUND "Could NOT find SDL2 (SDL2 is required by SDL2_ttf).")
+  if(SDL2_ttf_FIND_REQUIRED)
+    message(FATAL_ERROR ${SDL2_TTF_SDL2_NOT_FOUND})
+  else()
+      if(NOT SDL2_ttf_FIND_QUIETLY)
+        message(STATUS ${SDL2_TTF_SDL2_NOT_FOUND})
+      endif()
+    return()
+  endif()
+  unset(SDL2_TTF_SDL2_NOT_FOUND)
+endif()
+
+
+# Define options for searching SDL2_ttf Library in a custom path
+
+set(SDL2_TTF_PATH "" CACHE STRING "Custom SDL2_ttf Library path")
+
+set(_SDL2_TTF_NO_DEFAULT_PATH OFF)
+if(SDL2_TTF_PATH)
+  set(_SDL2_TTF_NO_DEFAULT_PATH ON)
+endif()
+
+set(SDL2_TTF_NO_DEFAULT_PATH ${_SDL2_TTF_NO_DEFAULT_PATH}
+    CACHE BOOL "Disable search SDL2_ttf Library in default path")
+unset(_SDL2_TTF_NO_DEFAULT_PATH)
+
+set(SDL2_TTF_NO_DEFAULT_PATH_CMD)
+if(SDL2_TTF_NO_DEFAULT_PATH)
+  set(SDL2_TTF_NO_DEFAULT_PATH_CMD NO_DEFAULT_PATH)
+endif()
+
+# Search for the SDL2_ttf include directory
 find_path(SDL2_TTF_INCLUDE_DIR SDL_ttf.h
-        HINTS
-        ENV SDL2TTFDIR
-        ENV SDL2DIR
-        PATH_SUFFIXES SDL2
-        # path suffixes to search inside ENV{SDLDIR}
-        include/SDL2 include
-        PATHS ${SDL2_TTF_PATH}
-        )
-
-if (CMAKE_SIZEOF_VOID_P EQUAL 8)
-    set(VC_LIB_PATH_SUFFIX lib/x64)
-else ()
-    set(VC_LIB_PATH_SUFFIX lib/x86)
-endif ()
+  HINTS
+    ENV SDL2TTFDIR
+    ENV SDL2DIR
+    ${SDL2_TTF_NO_DEFAULT_PATH_CMD}
+  PATH_SUFFIXES SDL2
+                # path suffixes to search inside ENV{SDL2DIR}
+                # and ENV{SDL2TTFDIR}
+                include/SDL2 include
+  PATHS ${SDL2_TTF_PATH}
+  DOC "Where the SDL2_ttf headers can be found"
+)
+
+if(CMAKE_SIZEOF_VOID_P EQUAL 8)
+  set(VC_LIB_PATH_SUFFIX lib/x64)
+else()
+  set(VC_LIB_PATH_SUFFIX lib/x86)
+endif()
 
+# Search for the SDL2_ttf library
 find_library(SDL2_TTF_LIBRARY
-        NAMES SDL2_ttf
-        HINTS
-        ENV SDL2TTFDIR
-        ENV SDL2DIR
-        PATH_SUFFIXES lib ${VC_LIB_PATH_SUFFIX}
-        PATHS ${SDL2_TTF_PATH}
-        )
-
-if (SDL2_TTF_INCLUDE_DIR AND EXISTS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h")
-    file(STRINGS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h" SDL2_TTF_VERSION_MAJOR_LINE REGEX "^#define[ \t]+SDL_TTF_MAJOR_VERSION[ \t]+[0-9]+$")
-    file(STRINGS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h" SDL2_TTF_VERSION_MINOR_LINE REGEX "^#define[ \t]+SDL_TTF_MINOR_VERSION[ \t]+[0-9]+$")
-    file(STRINGS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h" SDL2_TTF_VERSION_PATCH_LINE REGEX "^#define[ \t]+SDL_TTF_PATCHLEVEL[ \t]+[0-9]+$")
-    string(REGEX REPLACE "^#define[ \t]+SDL_TTF_MAJOR_VERSION[ \t]+([0-9]+)$" "\\1" SDL2_TTF_VERSION_MAJOR "${SDL2_TTF_VERSION_MAJOR_LINE}")
-    string(REGEX REPLACE "^#define[ \t]+SDL_TTF_MINOR_VERSION[ \t]+([0-9]+)$" "\\1" SDL2_TTF_VERSION_MINOR "${SDL2_TTF_VERSION_MINOR_LINE}")
-    string(REGEX REPLACE "^#define[ \t]+SDL_TTF_PATCHLEVEL[ \t]+([0-9]+)$" "\\1" SDL2_TTF_VERSION_PATCH "${SDL2_TTF_VERSION_PATCH_LINE}")
-    set(SDL2_TTF_VERSION_STRING ${SDL2_TTF_VERSION_MAJOR}.${SDL2_TTF_VERSION_MINOR}.${SDL2_TTF_VERSION_PATCH})
-    unset(SDL2_TTF_VERSION_MAJOR_LINE)
-    unset(SDL2_TTF_VERSION_MINOR_LINE)
-    unset(SDL2_TTF_VERSION_PATCH_LINE)
-    unset(SDL2_TTF_VERSION_MAJOR)
-    unset(SDL2_TTF_VERSION_MINOR)
-    unset(SDL2_TTF_VERSION_PATCH)
-endif ()
+  NAMES SDL2_ttf
+  HINTS
+    ENV SDL2TTFDIR
+    ENV SDL2DIR
+    ${SDL2_TTF_NO_DEFAULT_PATH_CMD}
+  PATH_SUFFIXES lib ${VC_LIB_PATH_SUFFIX}
+  PATHS ${SDL2_TTF_PATH}
+  DOC "Where the SDL2_ttf Library can be found"
+)
+
+# Read SDL2_ttf version
+if(SDL2_TTF_INCLUDE_DIR AND EXISTS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h")
+  file(STRINGS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h" SDL2_TTF_VERSION_MAJOR_LINE REGEX "^#define[ \t]+SDL_TTF_MAJOR_VERSION[ \t]+[0-9]+$")
+  file(STRINGS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h" SDL2_TTF_VERSION_MINOR_LINE REGEX "^#define[ \t]+SDL_TTF_MINOR_VERSION[ \t]+[0-9]+$")
+  file(STRINGS "${SDL2_TTF_INCLUDE_DIR}/SDL_ttf.h" SDL2_TTF_VERSION_PATCH_LINE REGEX "^#define[ \t]+SDL_TTF_PATCHLEVEL[ \t]+[0-9]+$")
+  string(REGEX REPLACE "^#define[ \t]+SDL_TTF_MAJOR_VERSION[ \t]+([0-9]+)$" "\\1" SDL2_TTF_VERSION_MAJOR "${SDL2_TTF_VERSION_MAJOR_LINE}")
+  string(REGEX REPLACE "^#define[ \t]+SDL_TTF_MINOR_VERSION[ \t]+([0-9]+)$" "\\1" SDL2_TTF_VERSION_MINOR "${SDL2_TTF_VERSION_MINOR_LINE}")
+  string(REGEX REPLACE "^#define[ \t]+SDL_TTF_PATCHLEVEL[ \t]+([0-9]+)$" "\\1" SDL2_TTF_VERSION_PATCH "${SDL2_TTF_VERSION_PATCH_LINE}")
+  set(SDL2_TTF_VERSION_STRING ${SDL2_TTF_VERSION_MAJOR}.${SDL2_TTF_VERSION_MINOR}.${SDL2_TTF_VERSION_PATCH})
+  unset(SDL2_TTF_VERSION_MAJOR_LINE)
+  unset(SDL2_TTF_VERSION_MINOR_LINE)
+  unset(SDL2_TTF_VERSION_PATCH_LINE)
+  unset(SDL2_TTF_VERSION_MAJOR)
+  unset(SDL2_TTF_VERSION_MINOR)
+  unset(SDL2_TTF_VERSION_PATCH)
+endif()
 
 set(SDL2_TTF_LIBRARIES ${SDL2_TTF_LIBRARY})
 set(SDL2_TTF_INCLUDE_DIRS ${SDL2_TTF_INCLUDE_DIR})
 
 include(FindPackageHandleStandardArgs)
 
 FIND_PACKAGE_HANDLE_STANDARD_ARGS(SDL2_ttf
-        REQUIRED_VARS SDL2_TTF_LIBRARIES SDL2_TTF_INCLUDE_DIRS
-        VERSION_VAR SDL2_TTF_VERSION_STRING)
+                                  REQUIRED_VARS SDL2_TTF_LIBRARIES SDL2_TTF_INCLUDE_DIRS
+                                  VERSION_VAR SDL2_TTF_VERSION_STRING)
+
+
+mark_as_advanced(SDL2_TTF_PATH
+                 SDL2_TTF_NO_DEFAULT_PATH
+                 SDL2_TTF_LIBRARY
+                 SDL2_TTF_INCLUDE_DIR)
+
+
+if(SDL2_TTF_FOUND)
 
-# for backward compatibility
-set(SDLTTF_LIBRARY ${SDL2_TTF_LIBRARIES})
-set(SDLTTF_INCLUDE_DIR ${SDL2_TTF_INCLUDE_DIRS})
-set(SDLTTF_FOUND ${SDL2_TTF_FOUND})
+  # SDL2::TTF target
+  if(SDL2_TTF_LIBRARY AND NOT TARGET SDL2::TTF)
+    add_library(SDL2::TTF UNKNOWN IMPORTED)
+    set_target_properties(SDL2::TTF PROPERTIES
+                          IMPORTED_LOCATION "${SDL2_TTF_LIBRARY}"
+                          INTERFACE_INCLUDE_DIRECTORIES "${SDL2_TTF_INCLUDE_DIR}"
+                          INTERFACE_LINK_LIBRARIES SDL2::Core)
+  endif()
+endif()

example/CMakeLists.txt

@@ -64,7 +64,7 @@ if (SDL2_FOUND AND SDL2_ttf_FOUND)
       counter/sdl2/main.cpp)
     target_include_directories(counter-sdl2 SYSTEM PUBLIC
       ${SDL2_INCLUDE_DIRS}
-      ${SDL2_TTF_INCLUDE_DIR})
+      ${SDL2_TTF_INCLUDE_DIRS})
     target_link_libraries(counter-sdl2
       lager-debugger-example
       ${SDL2_LIBRARIES}
@@ -76,7 +76,7 @@ if (SDL2_FOUND AND SDL2_ttf_FOUND)
       autopong/sdl2/main.cpp)
     target_include_directories(autopong SYSTEM PUBLIC
       ${SDL2_INCLUDE_DIRS}
-      ${SDL2_TTF_INCLUDE_DIR})
+      ${SDL2_TTF_INCLUDE_DIRS})
     target_link_libraries(autopong
       lager-debugger-example
       ${SDL2_LIBRARIES}
@@ -89,7 +89,7 @@ if (SDL2_FOUND AND SDL2_ttf_FOUND)
     target_compile_definitions(autopong-debug PUBLIC DEBUGGER)
     target_include_directories(autopong-debug SYSTEM PUBLIC
       ${SDL2_INCLUDE_DIRS}
-      ${SDL2_TTF_INCLUDE_DIR})
+      ${SDL2_TTF_INCLUDE_DIRS})
     target_link_libraries(autopong-debug
       lager-debugger-example
       ${SDL2_LIBRARIES}