DrawManager: Graph Task Scheduling

This patch uses a graph flow scheduler for creating all mesh batches.
On a Ryzen 1700 the framerate of Spring/020_02A.anim.blend went from 10 fps to 11.5 fps.

For each mesh where batches needs to be updated a sub-graph will be added to the task_graph.
This sub-graph starts with an extract_render_data_node. This fills/converts the required data
from Mesh.

Small extractions and extractions that can't be multi-threaded are grouped in a single
`extract_single_threaded_task_node`.

Other extractions will create a node for each loop exceeding 4096 items. these nodes are
linked to the `user_data_init_task_node`. the `user_data_init_task_node` prepares the userdata
needed for the extraction based on the data extracted from the mesh.

Note: If the `lines` and `lines_loose` are requested, the `lines_loose` sub-buffer is created
as part of the lines extraction. When the lines_loose is only requested the sub-buffer is
created from the existing `lines` buffer. It is assumed that the lines buffer is always
requested before or together with the lines_loose what is always the case (see
`DRW_batch_requested(cache->batch.loose_edges, GPU_PRIM_LINES)` in `draw_cache_impl_mesh.c`).

Reviewed By: Clément Foucault

Differential Revision: https://developer.blender.org/D7618

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/draw/intern/draw_manager.h b/source/blender/draw/intern/draw_manager.h
index f6d8179b193..a27af84fa02 100644
--- a/source/blender/draw/intern/draw_manager.h
+++ b/source/blender/draw/intern/draw_manager.h
@@ -31,6 +31,7 @@
 #include "BLI_assert.h"
 #include "BLI_linklist.h"
 #include "BLI_memblock.h"
+#include "BLI_task.h"
 #include "BLI_threads.h"
 
 #include "GPU_batch.h"
@@ -525,6 +526,8 @@ typedef struct DRWManager {
   uint select_id;
 #endif
 
+  struct TaskGraph *task_graph;
+
   /* ---------- Nothing after this point is cleared after use ----------- */
 
   /* gl_context serves as the offset for clearing only