Threaded object update and EvaluationContext

Summary:
Made objects update happening from multiple threads. It is a task-based
scheduling system which uses current dependency graph for spawning new
tasks. This means threading happens on object level, but the system is
flexible enough for higher granularity.

Technical details:

- Uses task scheduler which was recently committed to trunk
  (that one which Brecht ported from Cycles).

- Added two utility functions to dependency graph:
  * DAG_threaded_update_begin, which is called to  initialize threaded
    objects update. It will also schedule root DAG node to the queue,
    hence starting evaluation process.

    Initialization will calculate how much parents are to be evaluation
    before current DAG node can be scheduled. This value is used by task
    threads for faster detecting which nodes might be scheduled.

  * DAG_threaded_update_handle_node_updated which is  called from task
    thread function when node was fully handled.

	This function decreases num_pending_parents of node children and
	schedules children with zero valency.

    As it might have become clear, task thread receives DAG nodes and
    decides which callback to call for it.

    Currently only BKE_object_handle_update is called for object nodes.

    In the future it'll call node->callback() from Ali's new DAG.

- This required adding some workarounds to the render pipeline.
  Mainly to stop using get_object_dm() from modifiers' apply callback.
  Such a call was only a workaround for dependency graph glitch when
  rendering scene with, say, boolean modifiers before displaying
  this scene.

  Such change moves workaround from one place to another, so overall
  hackentropy remains the same.

- Added paradigm of EvaluaitonContext. Currently it's more like just a
  more reliable replacement for G.is_rendering which fails in some
  circumstances.

  Future idea of this context is to also store all the local data needed
  for objects evaluation such as local time, Copy-on-Write data and so.

  There're two types of EvaluationContext:

  * Context used for viewport updated and owned by Main. In the future
    this context might be easily moved to Window or Screen to allo
    per-window/per-screen local time.

  * Context used by render engines to evaluate objects for render purposes.
    Render engine is an owner of this context.

  This context is passed to all object update routines.

Reviewers: brecht, campbellbarton

Reviewed By: brecht

CC: lukastoenne

Differential Revision: https://developer.blender.org/D94

1 files changed, 32 insertions, 28 deletions

diff --git a/source/blender/blenkernel/intern/anim.c b/source/blender/blenkernel/intern/anim.c
index 1624a02e773..779593c2f76 100644
--- a/source/blender/blenkernel/intern/anim.c
+++ b/source/blender/blenkernel/intern/anim.c
@@ -76,7 +76,8 @@
 /* --------------------- */
 /* forward declarations */
 
-static void object_duplilist_recursive(ID *id, Scene *scene, Object *ob, ListBase *duplilist, float par_space_mat[4][4],
+static void object_duplilist_recursive(EvaluationContext *eval_ctx,
+                                       ID *id, Scene *scene, Object *ob, ListBase *duplilist, float par_space_mat[4][4],
                                        int persistent_id[MAX_DUPLI_RECUR], int level, int index, short flag);
 
 /* ******************************************************************** */
@@ -326,11 +327,10 @@ static void motionpaths_calc_optimise_depsgraph(Scene *scene, ListBase *targets)
 static void motionpaths_calc_update_scene(Scene *scene)
 {
 #if 1 // 'production' optimizations always on
-
 	/* rigid body simulation needs complete update to work correctly for now */
 	/* RB_TODO investigate if we could avoid updating everything */
 	if (BKE_scene_check_rigidbody_active(scene)) {
-		BKE_scene_update_for_newframe(G.main, scene, scene->lay);
+		BKE_scene_update_for_newframe(G.main->eval_ctx, G.main, scene, scene->lay);
 	}
 	else { /* otherwise we can optimize by restricting updates */
 		Base *base, *last = NULL;
@@ -352,7 +352,7 @@ static void motionpaths_calc_update_scene(Scene *scene)
 		 * is animated but not attached to/updatable from objects */
 		for (base = scene->base.first; base; base = base->next) {
 			/* update this object */
-			BKE_object_handle_update(scene, base->object);
+			BKE_object_handle_update(G.main->eval_ctx, scene, base->object);
 			
 			/* if this is the last one we need to update, let's stop to save some time */
 			if (base == last)
@@ -365,7 +365,7 @@ static void motionpaths_calc_update_scene(Scene *scene)
 	   *    that doesn't force complete update, but for now, this is the
 	   *    most accurate way!
 	   */
-	BKE_scene_update_for_newframe(G.main, scene, scene->lay); /* XXX this is the best way we can get anything moving */
+	BKE_scene_update_for_newframe(G.main->eval_ctx, G.main, scene, scene->lay); /* XXX this is the best way we can get anything moving */
 #endif
 }
 
@@ -745,7 +745,8 @@ static DupliObject *new_dupli_object(ListBase *lb, Object *ob, float mat[4][4],
 	return dob;
 }
 
-static void group_duplilist(ListBase *lb, Scene *scene, Object *ob, int persistent_id[MAX_DUPLI_RECUR],
+static void group_duplilist(EvaluationContext *eval_ctx,
+                            ListBase *lb, Scene *scene, Object *ob, int persistent_id[MAX_DUPLI_RECUR],
                             int level, short flag)
 {
 	DupliObject *dob;
@@ -775,7 +776,7 @@ static void group_duplilist(ListBase *lb, Scene *scene, Object *ob, int persiste
 	if (flag & DUPLILIST_DO_UPDATE) {
 		/* note: update is optional because we don't always need object
 		 * transformations to be correct. Also fixes bug [#29616]. */
-		BKE_group_handle_recalc_and_update(scene, ob, group);
+		BKE_group_handle_recalc_and_update(eval_ctx, scene, ob, group);
 	}
 
 	if (BKE_group_is_animated(group, ob))
@@ -792,15 +793,15 @@ static void group_duplilist(ListBase *lb, Scene *scene, Object *ob, int persiste
 
 			/* check the group instance and object layers match, also that the object visible flags are ok. */
 			if ((dob->origlay & group->layer) == 0 ||
-			    ((G.is_rendering == FALSE) && dob->ob->restrictflag & OB_RESTRICT_VIEW) ||
-			    ((G.is_rendering == TRUE)  && dob->ob->restrictflag & OB_RESTRICT_RENDER))
+			    ((eval_ctx->for_render == false) && dob->ob->restrictflag & OB_RESTRICT_VIEW) ||
+			    ((eval_ctx->for_render == true)  && dob->ob->restrictflag & OB_RESTRICT_RENDER))
 			{
 				dob->no_draw = TRUE;
 			}
 
 			if (go->ob->transflag & OB_DUPLI) {
 				copy_m4_m4(dob->ob->obmat, dob->mat);
-				object_duplilist_recursive(&group->id, scene, go->ob, lb, ob_obmat_ofs, persistent_id, level + 1, id, flag);
+				object_duplilist_recursive(eval_ctx, &group->id, scene, go->ob, lb, ob_obmat_ofs, persistent_id, level + 1, id, flag);
 				copy_m4_m4(dob->ob->obmat, dob->omat);
 			}
 		}
@@ -877,6 +878,7 @@ static void frames_duplilist(ListBase *lb, Scene *scene, Object *ob, int persist
 }
 
 typedef struct VertexDupliData {
+	EvaluationContext *eval_ctx;
 	ID *id; /* scene or group, for recursive loops */
 	int level;
 	short flag;
@@ -935,7 +937,7 @@ static void vertex_dupli__mapFunc(void *userData, int index, const float co[3],
 		float tmpmat[4][4];
 		copy_m4_m4(tmpmat, vdd->ob->obmat);
 		copy_m4_m4(vdd->ob->obmat, obmat); /* pretend we are really this mat */
-		object_duplilist_recursive((ID *)vdd->id, vdd->scene, vdd->ob, vdd->lb, obmat, vdd->persistent_id, vdd->level + 1, index, vdd->flag);
+		object_duplilist_recursive(vdd->eval_ctx, (ID *)vdd->id, vdd->scene, vdd->ob, vdd->lb, obmat, vdd->persistent_id, vdd->level + 1, index, vdd->flag);
 		copy_m4_m4(vdd->ob->obmat, tmpmat);
 	}
 }
@@ -1071,7 +1073,8 @@ static void vertex_duplilist(ListBase *lb, ID *id, Scene *scene, Object *par, fl
 	dm->release(dm);
 }
 
-static void face_duplilist(ListBase *lb, ID *id, Scene *scene, Object *par, float par_space_mat[4][4], int persistent_id[MAX_DUPLI_RECUR],
+static void face_duplilist(EvaluationContext *eval_ctx,
+                           ListBase *lb, ID *id, Scene *scene, Object *par, float par_space_mat[4][4], int persistent_id[MAX_DUPLI_RECUR],
                            int level, short flag)
 {
 	Object *ob, *ob_iter;
@@ -1237,7 +1240,7 @@ static void face_duplilist(ListBase *lb, ID *id, Scene *scene, Object *par, floa
 							float tmpmat[4][4];
 							copy_m4_m4(tmpmat, ob->obmat);
 							copy_m4_m4(ob->obmat, obmat); /* pretend we are really this mat */
-							object_duplilist_recursive((ID *)id, scene, ob, lb, ob->obmat, persistent_id, level + 1, a, flag);
+							object_duplilist_recursive(eval_ctx, (ID *)id, scene, ob, lb, ob->obmat, persistent_id, level + 1, a, flag);
 							copy_m4_m4(ob->obmat, tmpmat);
 						}
 					}
@@ -1254,7 +1257,8 @@ static void face_duplilist(ListBase *lb, ID *id, Scene *scene, Object *par, floa
 	dm->release(dm);
 }
 
-static void new_particle_duplilist(ListBase *lb, ID *id, Scene *scene, Object *par, float par_space_mat[4][4],
+static void new_particle_duplilist(EvaluationContext *eval_ctx,
+                                   ListBase *lb, ID *id, Scene *scene, Object *par, float par_space_mat[4][4],
                                    int persistent_id[MAX_DUPLI_RECUR], ParticleSystem *psys,
                                    int level, short flag)
 {
@@ -1289,7 +1293,7 @@ static void new_particle_duplilist(ListBase *lb, ID *id, Scene *scene, Object *p
 	if (!psys_check_enabled(par, psys))
 		return;
 
-	if (G.is_rendering == FALSE)
+	if (eval_ctx->for_render == false)
 		no_draw_flag |= PARS_NO_DISP;
 	
 	ctime = BKE_scene_frame_get(scene); /* NOTE: in old animsys, used parent object's timeoffset... */
@@ -1341,7 +1345,7 @@ static void new_particle_duplilist(ListBase *lb, ID *id, Scene *scene, Object *p
 		/* gather list of objects or single object */
 		if (part->ren_as == PART_DRAW_GR) {
 			if (flag & DUPLILIST_DO_UPDATE) {
-				BKE_group_handle_recalc_and_update(scene, par, part->dup_group);
+				BKE_group_handle_recalc_and_update(eval_ctx, scene, par, part->dup_group);
 			}
 
 			if (part->draw & PART_DRAW_COUNT_GR) {
@@ -1650,14 +1654,15 @@ static void font_duplilist(ListBase *lb, Scene *scene, Object *par, int persiste
 
 /* ------------- */
 
-static void object_duplilist_recursive(ID *id, Scene *scene, Object *ob, ListBase *duplilist, float par_space_mat[4][4],
+static void object_duplilist_recursive(EvaluationContext *eval_ctx,
+                                       ID *id, Scene *scene, Object *ob, ListBase *duplilist, float par_space_mat[4][4],
                                        int persistent_id[MAX_DUPLI_RECUR], int level, int index, short flag)
 {	
 	if ((ob->transflag & OB_DUPLI) == 0)
 		return;
 	
 	/* Should the dupli's be generated for this object? - Respect restrict flags */
-	if (G.is_rendering) {
+	if (eval_ctx->for_render) {
 		if (ob->restrictflag & OB_RESTRICT_RENDER) {
 			return;
 		}
@@ -1679,7 +1684,7 @@ static void object_duplilist_recursive(ID *id, Scene *scene, Object *ob, ListBas
 		/* particle system take up one level in id, the particles another */
 		for (; psys; psys = psys->next, psysid++) {
 			persistent_id[level] = psysid;
-			new_particle_duplilist(duplilist, id, scene, ob, par_space_mat, persistent_id, psys, level + 2, flag);
+			new_particle_duplilist(eval_ctx, duplilist, id, scene, ob, par_space_mat, persistent_id, psys, level + 2, flag);
 		}
 
 		persistent_id[level] = 0;
@@ -1696,7 +1701,7 @@ static void object_duplilist_recursive(ID *id, Scene *scene, Object *ob, ListBas
 	}
 	else if (ob->transflag & OB_DUPLIFACES) {
 		if (ob->type == OB_MESH)
-			face_duplilist(duplilist, id, scene, ob, par_space_mat, persistent_id, level + 1, flag);
+			face_duplilist(eval_ctx, duplilist, id, scene, ob, par_space_mat, persistent_id, level + 1, flag);
 	}
 	else if (ob->transflag & OB_DUPLIFRAMES) {
 		if (GS(id->name) == ID_SCE) { /* TODO - support dupligroups */
@@ -1706,7 +1711,7 @@ static void object_duplilist_recursive(ID *id, Scene *scene, Object *ob, ListBas
 	else if (ob->transflag & OB_DUPLIGROUP) {
 		DupliObject *dob;
 		
-		group_duplilist(duplilist, scene, ob, persistent_id, level + 1, flag); /* now recursive */
+		group_duplilist(eval_ctx, duplilist, scene, ob, persistent_id, level + 1, flag); /* now recursive */
 
 		if (level == 0) {
 			for (dob = duplilist->first; dob; dob = dob->next)
@@ -1722,31 +1727,30 @@ static void object_duplilist_recursive(ID *id, Scene *scene, Object *ob, ListBas
 
 /* Returns a list of DupliObject
  * note; group dupli's already set transform matrix. see note in group_duplilist() */
-ListBase *object_duplilist_ex(Scene *sce, Object *ob, bool update, bool for_render)
+ListBase *object_duplilist_ex(EvaluationContext *eval_ctx, Scene *sce, Object *ob, bool update)
 {
 	ListBase *duplilist = MEM_mallocN(sizeof(ListBase), "duplilist");
 	int persistent_id[MAX_DUPLI_RECUR] = {0};
 	int flag = 0;
 
 	/* don't allow BKE_object_handle_update for viewport during render, can crash */
-	if (update && !(G.is_rendering && !for_render))
+	if (update && !(G.is_rendering && !eval_ctx->for_render))
 		flag |= DUPLILIST_DO_UPDATE;
-	if (for_render)
+	if (eval_ctx->for_render)
 		flag |= DUPLILIST_FOR_RENDER;
 
 	duplilist->first = duplilist->last = NULL;
-	object_duplilist_recursive((ID *)sce, sce, ob, duplilist, NULL, persistent_id, 0, 0, flag);
+	object_duplilist_recursive(eval_ctx, (ID *)sce, sce, ob, duplilist, NULL, persistent_id, 0, 0, flag);
 	return duplilist;
 }
 
 /* note: previously updating was always done, this is why it defaults to be on
  * but there are likely places it can be called without updating */
-ListBase *object_duplilist(Scene *sce, Object *ob, bool for_render)
+ListBase *object_duplilist(EvaluationContext *eval_ctx, Scene *sce, Object *ob)
 {
-	return object_duplilist_ex(sce, ob, true, for_render);
+	return object_duplilist_ex(eval_ctx, sce, ob, true);
 }
 
-
 void free_object_duplilist(ListBase *lb)
 {
 	DupliObject *dob;