DrawManager: Cycles+GPencil

Fix for GPencil and Cycles Render draw type. GPencil objects were only
shown when overlays were turned on. The cause of this is an
optimization we did to not populate any draw engine when an
external renderer was used with overlays turned off.

This will check if there is any visible GPencil object in the scene. if
so it will still perform the loop.

`DEG_id_type_any_exists` can check if any object of a certain type_id is in the
result. This check is also being used to check if there are any
visible grease pencil objects as a precheck in `DRW_render_check_grease_pencil`.

Reviewed By: brecht, fclem, antoniov

Maniphest Tasks: T65191

Differential Revision: https://developer.blender.org/D4962

4 files changed, 16 insertions, 0 deletions

diff --git a/source/blender/depsgraph/DEG_depsgraph_query.h b/source/blender/depsgraph/DEG_depsgraph_query.h
index b9cbd75ce1e..48a62a69f30 100644
--- a/source/blender/depsgraph/DEG_depsgraph_query.h
+++ b/source/blender/depsgraph/DEG_depsgraph_query.h
@@ -67,6 +67,9 @@ float DEG_get_ctime(const Depsgraph *graph);
 bool DEG_id_type_updated(const struct Depsgraph *depsgraph, short id_type);
 bool DEG_id_type_any_updated(const struct Depsgraph *depsgraph);
 
+/* Check if given ID type is present in the depsgraph */
+bool DEG_id_type_any_exists(const struct Depsgraph *depsgraph, short id_type);
+
 /* Get additional evaluation flags for the given ID. */
 uint32_t DEG_get_eval_flags_for_id(const struct Depsgraph *graph, struct ID *id);
 
diff --git a/source/blender/depsgraph/intern/depsgraph.cc b/source/blender/depsgraph/intern/depsgraph.cc
index 5d96bfad95e..d8a9b41206b 100644
--- a/source/blender/depsgraph/intern/depsgraph.cc
+++ b/source/blender/depsgraph/intern/depsgraph.cc
@@ -38,6 +38,7 @@
 extern "C" {
 #include "BKE_scene.h"
 #include "BKE_global.h"
+#include "BKE_idcode.h"
 }
 
 #include "DEG_depsgraph.h"
@@ -81,6 +82,7 @@ Depsgraph::Depsgraph(Scene *scene, ViewLayer *view_layer, eEvaluationMode mode)
   entry_tags = BLI_gset_ptr_new("Depsgraph entry_tags");
   debug_flags = G.debug;
   memset(id_type_updated, 0, sizeof(id_type_updated));
+  memset(id_type_exist, 0, sizeof(id_type_exist));
   memset(physics_relations, 0, sizeof(physics_relations));
 }
 
@@ -130,6 +132,8 @@ IDNode *Depsgraph::add_id_node(ID *id, ID *id_cow_hint)
      * referencing to. */
     BLI_ghash_insert(id_hash, id, id_node);
     id_nodes.push_back(id_node);
+
+    id_type_exist[BKE_idcode_to_index(GS(id->name))] = 1;
   }
   return id_node;
 }
diff --git a/source/blender/depsgraph/intern/depsgraph.h b/source/blender/depsgraph/intern/depsgraph.h
index 073ec99b3aa..f194a44346b 100644
--- a/source/blender/depsgraph/intern/depsgraph.h
+++ b/source/blender/depsgraph/intern/depsgraph.h
@@ -152,6 +152,9 @@ struct Depsgraph {
   /* Indicates which ID types were updated. */
   char id_type_updated[MAX_LIBARRAY];
 
+  /* Indicates type of IDs present in the depsgraph. */
+  char id_type_exist[MAX_LIBARRAY];
+
   /* Quick-Access Temp Data ............. */
 
   /* Nodes which have been tagged as "directly modified". */
diff --git a/source/blender/depsgraph/intern/depsgraph_query.cc b/source/blender/depsgraph/intern/depsgraph_query.cc
index 326d852b1e1..0345f294860 100644
--- a/source/blender/depsgraph/intern/depsgraph_query.cc
+++ b/source/blender/depsgraph/intern/depsgraph_query.cc
@@ -95,6 +95,12 @@ bool DEG_id_type_any_updated(const Depsgraph *graph)
   return false;
 }
 
+bool DEG_id_type_any_exists(const Depsgraph *depsgraph, short id_type)
+{
+  const DEG::Depsgraph *deg_graph = reinterpret_cast<const DEG::Depsgraph *>(depsgraph);
+  return deg_graph->id_type_exist[BKE_idcode_to_index(id_type)] != 0;
+}
+
 uint32_t DEG_get_eval_flags_for_id(const Depsgraph *graph, ID *id)
 {
   if (graph == NULL) {