[Bf-blender-cvs] [d71543bf60f] functions: new utility to process a range with multiple threads

[Jacques Lucke]

Commit: d71543bf60f907d07d737ca519f358d4a6df5e77
Author: Jacques Lucke
Date:   Mon Jul 8 12:42:35 2019 +0200
Branches: functions
https://developer.blender.org/rBd71543bf60f907d07d737ca519f358d4a6df5e77

new utility to process a range with multiple threads

===================================================================

M	source/blender/blenlib/BLI_task.hpp

===================================================================

diff --git a/source/blender/blenlib/BLI_task.hpp b/source/blender/blenlib/BLI_task.hpp
index e872c237b7d..9854dbb1592 100644
--- a/source/blender/blenlib/BLI_task.hpp
+++ b/source/blender/blenlib/BLI_task.hpp
@@ -5,6 +5,7 @@
 #include "BLI_task.h"
 #include "BLI_array_ref.hpp"
 #include "BLI_small_map.hpp"
+#include "BLI_range.hpp"
 
 namespace BLI {
 namespace Task {
@@ -18,7 +19,7 @@ namespace Task {
 template<typename T, typename ProcessElement>
 static void parallel_array_elements(ArrayRef<T> array,
                                     ProcessElement process_element,
-                                    bool use_threading = false)
+                                    bool use_threading = true)
 {
   if (!use_threading) {
     for (T &element : array) {
@@ -54,7 +55,7 @@ static void parallel_array_elements(ArrayRef<T> array,
                                     ProcessElement process_element,
                                     CreateThreadLocal create_thread_local,
                                     FreeThreadLocal free_thread_local,
-                                    bool use_threading = false)
+                                    bool use_threading = true)
 {
   using LocalData = decltype(create_thread_local());
 
@@ -106,5 +107,37 @@ static void parallel_array_elements(ArrayRef<T> array,
   }
 }
 
+template<typename ProcessRange>
+static void parallel_range(Range<uint> total_range,
+                           uint chunk_size,
+                           ProcessRange process_range,
+                           bool use_threading = true)
+{
+  if (!use_threading) {
+    process_range(total_range);
+    return;
+  }
+
+  ParallelRangeSettings settings = {0};
+  BLI_parallel_range_settings_defaults(&settings);
+
+  struct ParallelData {
+    ChunkedRange<uint> chunks;
+    ProcessRange &process_range;
+  } data = {ChunkedRange<uint>(total_range, chunk_size), process_range};
+
+  BLI_task_parallel_range(0,
+                          data.chunks.chunks(),
+                          (void *)&data,
+                          [](void *__restrict userdata,
+                             const int index,
+                             const ParallelRangeTLS *__restrict UNUSED(tls)) {
+                            ParallelData &data = *(ParallelData *)userdata;
+                            Range<uint> range = data.chunks.chunk_range(index);
+                            data.process_range(range);
+                          },
+                          &settings);
+}
+
 }  // namespace Task
 }  // namespace BLI