Refactor: use 'BLI_task_parallel_range' in Draw Cache

One drawback to trying to predict the number of threads that will be
used in the `task_graph` is that we are only sure of the number when the
threads are running.

Using `BLI_task_parallel_range` allows the driver to
choose the best thread distribution through `parallel_reduce`.

The benefit is most evident on hardware with fewer cores.

This is the result on an 4-core laptop:
||before:|after:
|---|---|---|
|large_mesh_editing:|Average: 5.203638 FPS|Average: 5.398925 FPS
||rdata 15ms iter 43ms (frame 193ms)|rdata 14ms iter 36ms (frame 187ms)

Differential Revision: https://developer.blender.org/D11558

1 files changed, 1 insertions, 2 deletions

diff --git a/source/blender/gpu/intern/gpu_index_buffer.cc b/source/blender/gpu/intern/gpu_index_buffer.cc
index 993bcdf743b..be7470e79c1 100644
--- a/source/blender/gpu/intern/gpu_index_buffer.cc
+++ b/source/blender/gpu/intern/gpu_index_buffer.cc
@@ -79,8 +79,7 @@ GPUIndexBuf *GPU_indexbuf_build_on_device(uint index_len)
   return elem_;
 }
 
-void GPU_indexbuf_join_copies(GPUIndexBufBuilder *builder_to,
-                              const GPUIndexBufBuilder *builder_from)
+void GPU_indexbuf_join(GPUIndexBufBuilder *builder_to, const GPUIndexBufBuilder *builder_from)
 {
   BLI_assert(builder_to->data == builder_from->data);
   builder_to->index_len = max_uu(builder_to->index_len, builder_from->index_len);