CMake: Fix CPack dependencies for libpng 1.6

CHANGES

@@ -48,6 +48,7 @@ Misc:
  - Python: Integrate tests from cinema test suite
  - Util: Don't build crc32 if the function already exists
  - GBA: Detect hardware for Pokémon FireRed ROM hacks
+ - CMake: Fix CPack dependencies for libpng 1.6
 
 0.6.0: (2017-07-16)
 Features:

CMakeLists.txt

@@ -124,6 +124,7 @@ function(find_feature FEATURE_NAME FEATURE_REQUIRES)
 		set(${UREQUIRE}_CFLAGS_OTHER ${${REQUIRE}_CFLAGS_OTHER} PARENT_SCOPE)
 		set(${UREQUIRE}_FOUND ${${REQUIRE}_FOUND} PARENT_SCOPE)
 		set(${UREQUIRE}_INCLUDE_DIRS ${${REQUIRE}_INCLUDE_DIRS} PARENT_SCOPE)
+		set(${UREQUIRE}_VERSION_STRING ${${REQUIRE}_VERSION_STRING} PARENT_SCOPE)
 		if (APPLE)
 			set(IS_FRAMEWORK OFF)
 			set(LIBS)
@@ -526,7 +527,15 @@ if(USE_PNG)
 	list(APPEND FEATURES PNG)
 	include_directories(AFTER ${PNG_INCLUDE_DIRS})
 	list(APPEND DEPENDENCY_LIB ${PNG_LIBRARIES} ${ZLIB_LIBRARIES})
-	set(CPACK_DEBIAN_PACKAGE_DEPENDS "${CPACK_DEBIAN_PACKAGE_DEPENDS},libpng12-0")
+	if(PNG_VERSION_STRING)
+		string(REGEX MATCH "^[0-9]+\\.[0-9]+" PNG_VERSION_PARTIAL ${PNG_VERSION_STRING})
+		if(${PNG_VERSION_PARTIAL} STREQUAL "1.6")
+			set(PNG_DEB_VERSION "16-16")
+		else()
+			set(PNG_DEB_VERSION "12-0")
+		endif()
+		set(CPACK_DEBIAN_PACKAGE_DEPENDS "${CPACK_DEBIAN_PACKAGE_DEPENDS},libpng${PNG_DEB_VERSION}")
+	endif()
 endif()
 
 if(WANT_SQLITE3 AND NOT USE_SQLITE3)