Deps: Add potrace as a new library dependency

For work the GP team plans to land soon (T79877) potrace was taken
on as an additional optional dependency.

This diff adds building the library to the deps builder and takes
care of the integration into the build-system with the `WITH_POTRACE`
cmake switch.

Differential Revision: https://developer.blender.org/D8662

Reviewed by: brecht, sergey

1 files changed, 38 insertions, 0 deletions

diff --git a/build_files/build_environment/cmake/potrace.cmake b/build_files/build_environment/cmake/potrace.cmake
new file mode 100644
index 00000000000..28e57c8c54a
--- /dev/null
+++ b/build_files/build_environment/cmake/potrace.cmake
@@ -0,0 +1,38 @@
+# ***** 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.
+#
+# ***** END GPL LICENSE BLOCK *****
+
+set(POTRACE_EXTRA_ARGS
+)
+
+if((WIN32 AND BUILD_MODE STREQUAL Release) OR UNIX)
+  ExternalProject_Add(external_potrace
+    URL ${POTRACE_URI}
+    DOWNLOAD_DIR ${DOWNLOAD_DIR}
+    URL_HASH MD5=${POTRACE_HASH}
+    PREFIX ${BUILD_DIR}/potrace
+    PATCH_COMMAND ${CMAKE_COMMAND} -E copy ${PATCH_DIR}/cmakelists_potrace.txt ${BUILD_DIR}/potrace/src/external_potrace/CMakeLists.txt
+    CMAKE_ARGS -DCMAKE_INSTALL_PREFIX=${LIBDIR}/potrace ${DEFAULT_CMAKE_FLAGS} ${POTRACE_EXTRA_ARGS}
+    INSTALL_DIR ${LIBDIR}/potrace
+  )
+  if(WIN32)
+    ExternalProject_Add_Step(external_potrace after_install
+        COMMAND ${CMAKE_COMMAND} -E copy_directory ${LIBDIR}/potrace ${HARVEST_TARGET}/potrace
+        DEPENDEES install
+    )
+  endif()
+endif()