Fix rendering of wire curves when used as custom bone objects

In the current code we do not render any curves if they have not been
converted to meshes. This change makes the custom bone drawing try to
render mesh objects first and then falls back to curve objects if there
is no mesh data available.

Reviewed By: Clement

Differential Revision: http://developer.blender.org/D14804

4 files changed, 100 insertions, 28 deletions

diff --git a/source/blender/draw/engines/overlay/overlay_armature.c b/source/blender/draw/engines/overlay/overlay_armature.c
index 741259a95b2..ea0c2f287a6 100644
--- a/source/blender/draw/engines/overlay/overlay_armature.c
+++ b/source/blender/draw/engines/overlay/overlay_armature.c
@@ -628,22 +628,14 @@ BLI_INLINE DRWCallBuffer *custom_bone_instance_shgroup(ArmatureDrawContext *ctx,
   return buf;
 }
 
-static void drw_shgroup_bone_custom_solid(ArmatureDrawContext *ctx,
-                                          const float (*bone_mat)[4],
-                                          const float bone_color[4],
-                                          const float hint_color[4],
-                                          const float outline_color[4],
-                                          Object *custom)
+static void drw_shgroup_bone_custom_solid_mesh(ArmatureDrawContext *ctx,
+                                               Mesh *mesh,
+                                               const float (*bone_mat)[4],
+                                               const float bone_color[4],
+                                               const float hint_color[4],
+                                               const float outline_color[4],
+                                               Object *custom)
 {
-  /* The custom object is not an evaluated object, so its object->data field hasn't been replaced
-   * by #data_eval. This is bad since it gives preference to an object's evaluated mesh over any
-   * other data type, but supporting all evaluated geometry components would require a much larger
-   * refactor of this area. */
-  Mesh *mesh = BKE_object_get_evaluated_mesh_no_subsurf(custom);
-  if (mesh == NULL) {
-    return;
-  }
-
   /* TODO(fclem): arg... less than ideal but we never iter on this object
    * to assure batch cache is valid. */
   DRW_mesh_batch_cache_validate(custom, mesh);
@@ -682,16 +674,12 @@ static void drw_shgroup_bone_custom_solid(ArmatureDrawContext *ctx,
   drw_batch_cache_generate_requested_delayed(custom);
 }
 
-static void drw_shgroup_bone_custom_wire(ArmatureDrawContext *ctx,
-                                         const float (*bone_mat)[4],
-                                         const float color[4],
-                                         Object *custom)
+static void drw_shgroup_bone_custom_mesh_wire(ArmatureDrawContext *ctx,
+                                              Mesh *mesh,
+                                              const float (*bone_mat)[4],
+                                              const float color[4],
+                                              Object *custom)
 {
-  /* See comments in #drw_shgroup_bone_custom_solid. */
-  Mesh *mesh = BKE_object_get_evaluated_mesh_no_subsurf(custom);
-  if (mesh == NULL) {
-    return;
-  }
   /* TODO(fclem): arg... less than ideal but we never iter on this object
    * to assure batch cache is valid. */
   DRW_mesh_batch_cache_validate(custom, mesh);
@@ -710,6 +698,80 @@ static void drw_shgroup_bone_custom_wire(ArmatureDrawContext *ctx,
   drw_batch_cache_generate_requested_delayed(custom);
 }
 
+static void drw_shgroup_custom_bone_curve(ArmatureDrawContext *ctx,
+                                          Curve *curve,
+                                          const float (*bone_mat)[4],
+                                          const float outline_color[4],
+                                          Object *custom)
+{
+  /* TODO(fclem): arg... less than ideal but we never iter on this object
+   * to assure batch cache is valid. */
+  DRW_curve_batch_cache_validate(curve);
+
+  /* This only handles curves without any surface. The other curve types should have been converted
+   * to meshes and rendered in the mesh drawing function. */
+  struct GPUBatch *ledges = NULL;
+  if (custom->type == OB_FONT) {
+    ledges = DRW_cache_text_edge_wire_get(custom);
+  }
+  else {
+    ledges = DRW_cache_curve_edge_wire_get(custom);
+  }
+
+  if (ledges) {
+    BoneInstanceData inst_data;
+    mul_m4_m4m4(inst_data.mat, ctx->ob->obmat, bone_mat);
+
+    DRWCallBuffer *buf = custom_bone_instance_shgroup(ctx, ctx->custom_wire, ledges);
+    OVERLAY_bone_instance_data_set_color_hint(&inst_data, outline_color);
+    OVERLAY_bone_instance_data_set_color(&inst_data, outline_color);
+    DRW_buffer_add_entry_struct(buf, inst_data.mat);
+  }
+
+  /* TODO(fclem): needs to be moved elsewhere. */
+  drw_batch_cache_generate_requested_delayed(custom);
+}
+
+static void drw_shgroup_bone_custom_solid(ArmatureDrawContext *ctx,
+                                          const float (*bone_mat)[4],
+                                          const float bone_color[4],
+                                          const float hint_color[4],
+                                          const float outline_color[4],
+                                          Object *custom)
+{
+  /* The custom object is not an evaluated object, so its object->data field hasn't been replaced
+   * by #data_eval. This is bad since it gives preference to an object's evaluated mesh over any
+   * other data type, but supporting all evaluated geometry components would require a much
+   * larger refactor of this area. */
+  Mesh *mesh = BKE_object_get_evaluated_mesh_no_subsurf(custom);
+  if (mesh != NULL) {
+    drw_shgroup_bone_custom_solid_mesh(
+        ctx, mesh, bone_mat, bone_color, hint_color, outline_color, custom);
+    return;
+  }
+
+  if (ELEM(custom->type, OB_CURVES_LEGACY, OB_FONT, OB_SURF)) {
+    drw_shgroup_custom_bone_curve(ctx, custom->data, bone_mat, outline_color, custom);
+  }
+}
+
+static void drw_shgroup_bone_custom_wire(ArmatureDrawContext *ctx,
+                                         const float (*bone_mat)[4],
+                                         const float color[4],
+                                         Object *custom)
+{
+  /* See comments in #drw_shgroup_bone_custom_solid. */
+  Mesh *mesh = BKE_object_get_evaluated_mesh_no_subsurf(custom);
+  if (mesh != NULL) {
+    drw_shgroup_bone_custom_mesh_wire(ctx, mesh, bone_mat, color, custom);
+    return;
+  }
+
+  if (ELEM(custom->type, OB_CURVES_LEGACY, OB_FONT, OB_SURF)) {
+    drw_shgroup_custom_bone_curve(ctx, custom->data, bone_mat, color, custom);
+  }
+}
+
 static void drw_shgroup_bone_custom_empty(ArmatureDrawContext *ctx,
                                           const float (*bone_mat)[4],
                                           const float color[4],
diff --git a/source/blender/draw/intern/draw_cache.c b/source/blender/draw/intern/draw_cache.c
index e606d67df25..19d6557c34a 100644
--- a/source/blender/draw/intern/draw_cache.c
+++ b/source/blender/draw/intern/draw_cache.c
@@ -3357,7 +3357,7 @@ void drw_batch_cache_generate_requested(Object *ob)
   }
 }
 
-void drw_batch_cache_generate_requested_evaluated_mesh(Object *ob)
+void drw_batch_cache_generate_requested_evaluated_mesh_or_curve(Object *ob)
 {
   /* NOTE: Logic here is duplicated from #drw_batch_cache_generate_requested. */
 
@@ -3374,7 +3374,17 @@ void drw_batch_cache_generate_requested_evaluated_mesh(Object *ob)
                           ((mode == CTX_MODE_EDIT_MESH) && DRW_object_is_in_edit_mode(ob))));
 
   Mesh *mesh = BKE_object_get_evaluated_mesh_no_subsurf(ob);
-  DRW_mesh_batch_cache_create_requested(DST.task_graph, ob, mesh, scene, is_paint_mode, use_hide);
+  /* Try getting the mesh first and if that fails, try getting the curve data.
+   * If the curves are surfaces or have certain modifiers applied to them, the will have mesh data
+   * of the final result.
+   */
+  if (mesh != NULL) {
+    DRW_mesh_batch_cache_create_requested(
+        DST.task_graph, ob, mesh, scene, is_paint_mode, use_hide);
+  }
+  else if (ELEM(ob->type, OB_CURVES_LEGACY, OB_FONT, OB_SURF)) {
+    DRW_curve_batch_cache_create_requested(ob, scene);
+  }
 }
 
 void drw_batch_cache_generate_requested_delayed(Object *ob)
diff --git a/source/blender/draw/intern/draw_manager.c b/source/blender/draw/intern/draw_manager.c
index adf9d4a13df..6ab8d30109e 100644
--- a/source/blender/draw/intern/draw_manager.c
+++ b/source/blender/draw/intern/draw_manager.c
@@ -164,7 +164,7 @@ static void drw_task_graph_deinit(void)
   BLI_task_graph_work_and_wait(DST.task_graph);
 
   BLI_gset_free(DST.delayed_extraction,
-                (void (*)(void *key))drw_batch_cache_generate_requested_evaluated_mesh);
+                (void (*)(void *key))drw_batch_cache_generate_requested_evaluated_mesh_or_curve);
   DST.delayed_extraction = NULL;
   BLI_task_graph_work_and_wait(DST.task_graph);
 
diff --git a/source/blender/draw/intern/draw_manager.h b/source/blender/draw/intern/draw_manager.h
index 8812f112014..7a9585262ff 100644
--- a/source/blender/draw/intern/draw_manager.h
+++ b/source/blender/draw/intern/draw_manager.h
@@ -671,7 +671,7 @@ void drw_batch_cache_generate_requested(struct Object *ob);
  * \warning Only evaluated mesh data is handled by this delayed generation.
  */
 void drw_batch_cache_generate_requested_delayed(Object *ob);
-void drw_batch_cache_generate_requested_evaluated_mesh(Object *ob);
+void drw_batch_cache_generate_requested_evaluated_mesh_or_curve(Object *ob);
 
 void drw_resource_buffer_finish(DRWData *vmempool);