From 2c6c19d656a0f2f01debfc9f95a9e8edfa0ca5c5 Mon Sep 17 00:00:00 2001
From: Chris Russ <christoph.russ@roames.com.au>
Date: Wed, 22 Jun 2016 17:38:10 +1000
Subject: [PATCH] allowing to enable building of zlib manually

---
 CMakeLists.txt | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6e9406689..d04abe3bb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 # Open Asset Import Library (assimp)
 # ----------------------------------------------------------------------
-# 
+#
 # Copyright (c) 2006-2016, assimp team
 # All rights reserved.
 #
@@ -175,7 +175,15 @@ ENDIF( CMAKE_COMPILER_IS_GNUCXX )
 
 # Search for external dependencies, and build them from source if not found
 # Search for zlib
-find_package(ZLIB)
+OPTION(ASSIMP_BUILD_ZLIB
+    "Build your own zlib"
+    OFF
+)
+
+IF ( NOT ASSIMP_BUILD_ZLIB )
+    find_package(ZLIB)
+ENDIF(ASSIMP_BUILD_ZLIB)
+
 IF( NOT ZLIB_FOUND )
   message(STATUS "compiling zlib from souces")
   include(CheckIncludeFile)
@@ -278,7 +286,7 @@ IF ( ASSIMP_BUILD_ASSIMP_TOOLS )
       ADD_SUBDIRECTORY( tools/assimp_view/ )
     ENDIF ( ASSIMP_BUILD_ASSIMP_VIEW )
   ENDIF ( WIN32 )
-  
+
   ADD_SUBDIRECTORY( tools/assimp_cmd/ )
 ENDIF ( ASSIMP_BUILD_ASSIMP_TOOLS )