Deduplicate CUDA and OpenCL wranglers

For now it was mainly about OpenCL wrangler being duplicated
between Cycles and Compositor, but with OpenSubdiv work those
wranglers were gonna to be duplicated just once again.

This commit makes it so Cycles and Compositor uses wranglers
from this repositories:

  - https://github.com/CudaWrangler/cuew
  - https://github.com/OpenCLWrangler/clew

This repositories are based on the wranglers we used before
and they'll be likely continued maintaining by us plus some
more players in the market.

Pretty much straightforward change with some tricks in the
CMake/SCons to make this libs being passed to the linker
after all other libraries in order to make OpenSubdiv linked
against those wranglers in the future.

For those who're worrying about Cycles being less standalone,
it's not truth, it's rather more flexible now and in the future
different wranglers might be used in Cycles. For now it'll
just mean those libs would need to be put into Cycles repository
together with some other libs from Blender such as mikkspace.

This is mainly platform maintenance commit, should not be any
changes to the user space.

Reviewers: juicyfruit, dingto, campbellbarton

Reviewed By: juicyfruit, dingto, campbellbarton

Differential Revision: https://developer.blender.org/D707

1 files changed, 42 insertions, 0 deletions

diff --git a/extern/clew/CMakeLists.txt b/extern/clew/CMakeLists.txt
new file mode 100644
index 00000000000..f75e933034f
--- /dev/null
+++ b/extern/clew/CMakeLists.txt
@@ -0,0 +1,42 @@
+# ***** BEGIN GPL LICENSE BLOCK *****
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# The Original Code is Copyright (C) 2006, Blender Foundation
+# All rights reserved.
+#
+# The Original Code is: all of this file.
+#
+# Contributor(s): Jacques Beaurain.
+#
+# ***** END GPL LICENSE BLOCK *****
+
+set(INC
+	.
+	include
+)
+
+set(INC_SYS
+
+)
+
+set(SRC
+	include/clew.h
+	src/clew.c
+)
+
+add_definitions(-DCL_USE_DEPRECATED_OPENCL_1_1_APIS)
+
+blender_add_lib(extern_clew "${SRC}" "${INC}" "${INC_SYS}")