Merge pull request #63 from psychocrypt/fix-selectWrongOpenCL

prefere AMD OpenCL over NVIDIA, Intel

CMakeLists.txt

@@ -180,6 +180,38 @@ list(APPEND CMAKE_PREFIX_PATH "$ENV{CMAKE_PREFIX_PATH}")
 
 option(OpenCL_ENABLE "Enable or disable OpenCL spport (AMD GPU support)" ON)
 if(OpenCL_ENABLE)
+    # try to find AMD OpenCL before NVIDIA OpenCL
+    find_path(OpenCL_INCLUDE_DIR
+        NAMES
+            CL/cl.h
+            OpenCL/cl.h
+        NO_DEFAULT_PATH
+        PATHS
+            ENV "OpenCL_ROOT"
+            ENV AMDAPPSDKROOT
+            ENV ATISTREAMSDKROOT
+            ENV "PROGRAMFILES(X86)"
+        PATH_SUFFIXES
+            include
+            OpenCL/common/inc
+            "AMD APP/include")
+
+    find_library(OpenCL_LIBRARY
+        NAMES 
+            OpenCL
+            OpenCL.lib
+        NO_DEFAULT_PATH
+        PATHS
+            ENV "OpenCL_ROOT"
+            ENV AMDAPPSDKROOT
+            ENV ATISTREAMSDKROOT
+            ENV "PROGRAMFILES(X86)"
+        PATH_SUFFIXES
+            "AMD APP/lib/x86_64"
+            lib/x86_64
+            lib/x64
+            OpenCL/common/lib/x64)
+    # find package will use the previews searched path variables
     find_package(OpenCL)
     if(OpenCL_FOUND)
         include_directories(SYSTEM ${OpenCL_INCLUDE_DIRS})