From d62dda3b030e31f322aaa47b4aeaa0a12fa3201b Mon Sep 17 00:00:00 2001
From: Patrick Bader <mail@patrickbader.eu>
Date: Thu, 5 Jan 2017 16:48:04 +0100
Subject: [PATCH] forces CMake use zlib version which is installed by vcpkg.

---
 ports/libpng/portfile.cmake      |  6 +++++-
 ports/libpng/set_zlib_root.patch | 12 ++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)
 create mode 100644 ports/libpng/set_zlib_root.patch

diff --git a/ports/libpng/portfile.cmake b/ports/libpng/portfile.cmake
index f7be6cca1..55cbb4bda 100644
--- a/ports/libpng/portfile.cmake
+++ b/ports/libpng/portfile.cmake
@@ -9,7 +9,9 @@ vcpkg_download_distfile(ARCHIVE
 vcpkg_extract_source_archive(${ARCHIVE})
 vcpkg_apply_patches(
     SOURCE_PATH ${SOURCE_PATH}
-    PATCHES "${CMAKE_CURRENT_LIST_DIR}/use-abort-on-all-platforms.patch"
+    PATCHES 
+		"${CMAKE_CURRENT_LIST_DIR}/use-abort-on-all-platforms.patch"
+		"${CMAKE_CURRENT_LIST_DIR}/set_zlib_root.patch"
 )
 
 if(VCPKG_LIBRARY_LINKAGE STREQUAL dynamic)
@@ -19,6 +21,7 @@ else()
     set(PNG_STATIC_LIBS ON)
     set(PNG_SHARED_LIBS OFF)
 endif()
+#message(STATUS ${CURRENT_INSTALL_DIR})
 
 vcpkg_configure_cmake(
     SOURCE_PATH ${SOURCE_PATH}
@@ -29,6 +32,7 @@ vcpkg_configure_cmake(
         -DSKIP_INSTALL_PROGRAMS=ON
         -DSKIP_INSTALL_EXECUTABLES=ON
         -DSKIP_INSTALL_FILES=ON
+		-DINSTALLED_DIR:PATH=${CURRENT_INSTALLED_DIR}
     OPTIONS_DEBUG
         -DSKIP_INSTALL_HEADERS=ON
 )
diff --git a/ports/libpng/set_zlib_root.patch b/ports/libpng/set_zlib_root.patch
new file mode 100644
index 000000000..8fb029635
--- /dev/null
+++ b/ports/libpng/set_zlib_root.patch
@@ -0,0 +1,12 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 186b65a..e485fd9 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -40,6 +40,7 @@ set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
+ set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
+ 
+ # needed packages
++set(ZLIB_ROOT ${INSTALLED_DIR})
+ find_package(ZLIB REQUIRED)
+ include_directories(${ZLIB_INCLUDE_DIR})
+