Implement CPPAN support for easy Windows building.

.gitignore

@@ -73,4 +73,5 @@ kernel*.bin
 
 # build dirs
 /build*
+/cppan
 /win*

CMakeLists.txt

@@ -46,11 +46,15 @@ set(VERSION_PLAIN ${VERSION_MAJOR}.${VERSION_MINOR})
 
 set(MINIMUM_LEPTONICA_VERSION 1.71)
 
-if (NOT Leptonica_DIR AND NOT MSVC)
-find_package(PkgConfig REQUIRED)
-pkg_check_modules(Leptonica REQUIRED lept)
+if(NOT EXISTS ${PROJECT_SOURCE_DIR}/cppan)
+    if (NOT Leptonica_DIR AND NOT MSVC)
+        find_package(PkgConfig REQUIRED)
+        pkg_check_modules(Leptonica REQUIRED lept)
+    else()
+        find_package(Leptonica ${MINIMUM_LEPTONICA_VERSION} REQUIRED CONFIG)
+    endif()
 else()
-find_package(Leptonica ${MINIMUM_LEPTONICA_VERSION} REQUIRED CONFIG)
+    add_subdirectory(cppan)
 endif()
 
 find_package(OpenCL QUIET)
@@ -201,15 +205,22 @@ add_library                     (tesseract ${LIBRARY_TYPE} ${tesseract_src} ${te
 if (NOT STATIC)
 target_compile_definitions      (tesseract PUBLIC -DTESS_EXPORTS)
 endif()
-target_link_libraries           (tesseract ${Leptonica_LIBRARIES} ${LIB_Ws2_32} ${LIB_pthread})
+target_link_libraries           (tesseract ${LIB_Ws2_32} ${LIB_pthread})
 set_target_properties           (tesseract PROPERTIES VERSION ${VERSION_MAJOR}.${VERSION_MINOR_0}.${VERSION_MINOR_1})
 set_target_properties           (tesseract PROPERTIES SOVERSION ${VERSION_MAJOR}.${VERSION_MINOR_0}.${VERSION_MINOR_1})
 if (WIN32)
 set_target_properties           (tesseract PROPERTIES OUTPUT_NAME tesseract${VERSION_MAJOR}${VERSION_MINOR})
 set_target_properties           (tesseract PROPERTIES DEBUG_OUTPUT_NAME tesseract${VERSION_MAJOR}${VERSION_MINOR}d)
 endif()
-export(TARGETS tesseract FILE ${CMAKE_BINARY_DIR}/TesseractTargets.cmake)
 
+if (NOT USES_CPPAN)
+    target_link_libraries       (tesseract ${Leptonica_LIBRARIES})
+    export(TARGETS tesseract FILE ${CMAKE_BINARY_DIR}/TesseractTargets.cmake)
+else()
+    target_link_libraries       (tesseract cppan)
+    file(WRITE ${CMAKE_BINARY_DIR}/TesseractTargets.cmake "include(${CMAKE_BINARY_DIR}/cppan.cmake)\n")
+    export(TARGETS tesseract APPEND FILE ${CMAKE_BINARY_DIR}/TesseractTargets.cmake)
+endif()
 
 ########################################
 # EXECUTABLE tesseractmain

cppan.yml

@@ -0,0 +1,2 @@
+dependencies:
+  pvt.cppan.demo.leptonica: master