[Bf-blender-cvs] [4090f06b2db] tmp-eevee-material-refactor: DRW: Add pass chaining and instances

[Clément Foucault]

Commit: 4090f06b2dbfe91119697ea0ede3d7cd625c4cb4
Author: Clément Foucault
Date:   Fri May 8 15:27:55 2020 +0200
Branches: tmp-eevee-material-refactor
https://developer.blender.org/rB4090f06b2dbfe91119697ea0ede3d7cd625c4cb4

DRW: Add pass chaining and instances

Instancing will draw the same shgroups but with the instancer pass' state.

Chaining (linking) will render multiple passes by just calling DRW_draw_pass
on the first one.

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

M	source/blender/draw/intern/DRW_render.h
M	source/blender/draw/intern/draw_manager.h
M	source/blender/draw/intern/draw_manager_data.c
M	source/blender/draw/intern/draw_manager_exec.c

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

diff --git a/source/blender/draw/intern/DRW_render.h b/source/blender/draw/intern/DRW_render.h
index bccecc8059a..76666e167a1 100644
--- a/source/blender/draw/intern/DRW_render.h
+++ b/source/blender/draw/intern/DRW_render.h
@@ -535,6 +535,8 @@ bool DRW_shgroup_is_empty(DRWShadingGroup *shgroup);
 
 /* Passes */
 DRWPass *DRW_pass_create(const char *name, DRWState state);
+DRWPass *DRW_pass_create_instance(const char *name, DRWPass *original, DRWState state);
+void DRW_pass_link(DRWPass *first, DRWPass *second);
 /* TODO Replace with passes inheritance. */
 void DRW_pass_state_set(DRWPass *pass, DRWState state);
 void DRW_pass_state_add(DRWPass *pass, DRWState state);
@@ -548,6 +550,8 @@ void DRW_pass_sort_shgroup_reverse(DRWPass *pass);
 bool DRW_pass_is_empty(DRWPass *pass);
 
 #define DRW_PASS_CREATE(pass, state) (pass = DRW_pass_create(#pass, state))
+#define DRW_PASS_INSTANCE_CREATE(pass, original, state) \
+  (pass = DRW_pass_create_instance(#pass, (original), state))
 
 /* Views */
 DRWView *DRW_view_create(const float viewmat[4][4],
diff --git a/source/blender/draw/intern/draw_manager.h b/source/blender/draw/intern/draw_manager.h
index e213ba64497..09ffb8f01dd 100644
--- a/source/blender/draw/intern/draw_manager.h
+++ b/source/blender/draw/intern/draw_manager.h
@@ -345,6 +345,13 @@ struct DRWPass {
     DRWShadingGroup *last;
   } shgroups;
 
+  /* Draw the shgroups of this pass instead.
+   * This avoid duplicating drawcalls/shgroups
+   * for similar passes. */
+  DRWPass *original;
+  /* Link list of additional passes to render. */
+  DRWPass *next;
+
   DRWResourceHandle handle;
   DRWState state;
   char name[MAX_PASS_NAME];
diff --git a/source/blender/draw/intern/draw_manager_data.c b/source/blender/draw/intern/draw_manager_data.c
index 225a15236d9..0145e62e68b 100644
--- a/source/blender/draw/intern/draw_manager_data.c
+++ b/source/blender/draw/intern/draw_manager_data.c
@@ -1937,9 +1937,28 @@ DRWPass *DRW_pass_create(const char *name, DRWState state)
   pass->handle = DST.pass_handle;
   DRW_handle_increment(&DST.pass_handle);
 
+  pass->original = NULL;
+  pass->next = NULL;
+
   return pass;
 }
 
+DRWPass *DRW_pass_create_instance(const char *name, DRWPass *original, DRWState state)
+{
+  DRWPass *pass = DRW_pass_create(name, state);
+  pass->original = original;
+
+  return pass;
+}
+
+/* Link two passes so that they are both rendered if the first one is being drawn. */
+void DRW_pass_link(DRWPass *first, DRWPass *second)
+{
+  BLI_assert(first != second);
+  BLI_assert(first->next == NULL);
+  first->next = second;
+}
+
 bool DRW_pass_is_empty(DRWPass *pass)
 {
   LISTBASE_FOREACH (DRWShadingGroup *, shgroup, &pass->shgroups) {
diff --git a/source/blender/draw/intern/draw_manager_exec.c b/source/blender/draw/intern/draw_manager_exec.c
index b6aa456e240..4aaa9b8847e 100644
--- a/source/blender/draw/intern/draw_manager_exec.c
+++ b/source/blender/draw/intern/draw_manager_exec.c
@@ -1442,6 +1442,11 @@ static void drw_draw_pass_ex(DRWPass *pass,
                              DRWShadingGroup *start_group,
                              DRWShadingGroup *end_group)
 {
+  if (pass->original) {
+    start_group = pass->original->shgroups.first;
+    end_group = pass->original->shgroups.last;
+  }
+
   if (start_group == NULL) {
     return;
   }
@@ -1528,6 +1533,9 @@ static void drw_draw_pass_ex(DRWPass *pass,
 void DRW_draw_pass(DRWPass *pass)
 {
   drw_draw_pass_ex(pass, pass->shgroups.first, pass->shgroups.last);
+  while ((pass = pass->next)) {
+    DRW_draw_pass(pass);
+  }
 }
 
 /* Draw only a subset of shgroups. Used in special situations as grease pencil strokes */