Functions: Multi Function

This adds the `MultiFunction` type and some smallish utility types that it uses.
A `MultiFunction` encapsulates a function that is optimized for throughput by
always processing many elements at once.

This is an important part of the new particle system, because it allows us to
execute user generated node trees for many particles efficiently.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D8030

1 files changed, 49 insertions, 0 deletions

diff --git a/source/blender/functions/FN_multi_function_context.hh b/source/blender/functions/FN_multi_function_context.hh
new file mode 100644
index 00000000000..d1283639467
--- /dev/null
+++ b/source/blender/functions/FN_multi_function_context.hh
@@ -0,0 +1,49 @@
+/*
+ * 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.
+ */
+
+#ifndef __FN_MULTI_FUNCTION_CONTEXT_HH__
+#define __FN_MULTI_FUNCTION_CONTEXT_HH__
+
+/** \file
+ * \ingroup fn
+ *
+ * An MFContext is passed along with every call to a multi-function. Right now it does nothing, but
+ * it can be used for the following purposes:
+ * - Pass debug information up and down the function call stack.
+ * - Pass reusable memory buffers to subfunctions to increase performance.
+ * - Pass cached data to called functions.
+ */
+
+namespace blender {
+namespace fn {
+
+class MFContextBuilder {
+};
+
+class MFContext {
+ private:
+  MFContextBuilder *m_builder;
+
+ public:
+  MFContext(MFContextBuilder &builder) : m_builder(&builder)
+  {
+  }
+};
+
+}  // namespace fn
+}  // namespace blender
+
+#endif /* __FN_MULTI_FUNCTION_CONTEXT_HH__ */