Fluid: More stable flow emission

Reverting some changes that were made in 33317b464777

3 files changed, 15 insertions, 45 deletions

diff --git a/intern/mantaflow/intern/strings/liquid_script.h b/intern/mantaflow/intern/strings/liquid_script.h
index bb42b781c19..442b09b5a8a 100644
--- a/intern/mantaflow/intern/strings/liquid_script.h
+++ b/intern/mantaflow/intern/strings/liquid_script.h
@@ -139,7 +139,7 @@ waveCrest_sp$ID$     = sp$ID$.create(RealGrid)\n\
 kineticEnergy_sp$ID$ = sp$ID$.create(RealGrid)\n\
 \n\
 # Keep track of important objects in dict to load them later on\n\
-liquid_particles_dict_final_s$ID$   = dict(ppSnd=ppSnd_sp$ID$, pVelSnd=pVelSnd_pp$ID$, pLifeSnd=pLifeSnd_pp$ID$)\n\
+liquid_particles_dict_final_s$ID$  = dict(ppSnd=ppSnd_sp$ID$, pVelSnd=pVelSnd_pp$ID$, pLifeSnd=pLifeSnd_pp$ID$)\n\
 liquid_particles_dict_resume_s$ID$ = dict(trappedAir=trappedAir_sp$ID$, waveCrest=waveCrest_sp$ID$, kineticEnergy=kineticEnergy_sp$ID$)\n";
 
 const std::string liquid_init_phi =
@@ -166,15 +166,18 @@ def liquid_adaptive_step_$ID$(framenr):\n\
         mantaMsg('Initializing obstacle levelset')\n\
         phiObsIn_s$ID$.fillHoles(maxDepth=int(res_s$ID$), boundaryWidth=2)\n\
         extrapolateLsSimple(phi=phiObsIn_s$ID$, distance=int(res_s$ID$/2), inside=True)\n\
-        extrapolateLsSimple(phi=phiObsIn_s$ID$, distance=int(res_s$ID$/2), inside=False)\n\
+        extrapolateLsSimple(phi=phiObsIn_s$ID$, distance=3, inside=False)\n\
         phiObs_s$ID$.join(phiObsIn_s$ID$)\n\
         \n\
         # Using boundaryWidth=2 to not search beginning from walls (just a performance optimization)\n\
         # Additional sanity check: fill holes in phiObs which can result after joining with phiObsIn\n\
         phiObs_s$ID$.fillHoles(maxDepth=int(res_s$ID$), boundaryWidth=2)\n\
         extrapolateLsSimple(phi=phiObs_s$ID$, distance=int(res_s$ID$/2), inside=True)\n\
-        extrapolateLsSimple(phi=phiObs_s$ID$, distance=int(res_s$ID$/2), inside=False)\n\
+        extrapolateLsSimple(phi=phiObs_s$ID$, distance=3, inside=False)\n\
     \n\
+    mantaMsg('Initializing fluid levelset')\n\
+    extrapolateLsSimple(phi=phiIn_s$ID$, distance=int(res_s$ID$/2), inside=True)\n\
+    extrapolateLsSimple(phi=phiIn_s$ID$, distance=int(res_s$ID$/2), inside=False)\n\
     phi_s$ID$.join(phiIn_s$ID$)\n\
     \n\
     if using_obstacle_s$ID$:\n\
diff --git a/intern/mantaflow/intern/strings/smoke_script.h b/intern/mantaflow/intern/strings/smoke_script.h
index ad966503fd1..b4f7a39adeb 100644
--- a/intern/mantaflow/intern/strings/smoke_script.h
+++ b/intern/mantaflow/intern/strings/smoke_script.h
@@ -279,14 +279,18 @@ def smoke_adaptive_step_$ID$(framenr):\n\
         mantaMsg('Initializing obstacle levelset')\n\
         phiObsIn_s$ID$.fillHoles(maxDepth=int(res_s$ID$), boundaryWidth=2)\n\
         extrapolateLsSimple(phi=phiObsIn_s$ID$, distance=int(res_s$ID$/2), inside=True)\n\
-        extrapolateLsSimple(phi=phiObsIn_s$ID$, distance=int(res_s$ID$/2), inside=False)\n\
+        extrapolateLsSimple(phi=phiObsIn_s$ID$, distance=3, inside=False)\n\
         phiObs_s$ID$.join(phiObsIn_s$ID$)\n\
         \n\
         # Using boundaryWidth=2 to not search beginning from walls (just a performance optimization)\n\
         # Additional sanity check: fill holes in phiObs which can result after joining with phiObsIn\n\
         phiObs_s$ID$.fillHoles(maxDepth=int(res_s$ID$), boundaryWidth=2)\n\
         extrapolateLsSimple(phi=phiObs_s$ID$, distance=int(res_s$ID$/2), inside=True)\n\
-        extrapolateLsSimple(phi=phiObs_s$ID$, distance=int(res_s$ID$/2), inside=False)\n\
+        extrapolateLsSimple(phi=phiObs_s$ID$, distance=3, inside=False)\n\
+    \n\
+    mantaMsg('Initializing fluid levelset')\n\
+    extrapolateLsSimple(phi=phiIn_s$ID$, distance=int(res_s$ID$/2), inside=True)\n\
+    extrapolateLsSimple(phi=phiIn_s$ID$, distance=3, inside=False)\n\
     \n\
     if using_outflow_s$ID$:\n\
         phiOut_s$ID$.join(phiOutIn_s$ID$)\n\
diff --git a/source/blender/blenkernel/intern/fluid.c b/source/blender/blenkernel/intern/fluid.c
index b8d7429fa94..f19137bf796 100644
--- a/source/blender/blenkernel/intern/fluid.c
+++ b/source/blender/blenkernel/intern/fluid.c
@@ -1452,7 +1452,7 @@ static void update_mesh_distances(int index,
     return;
   }
 
-  /* b) Volumetric initialization: 1) Ray-casts around mesh object. */
+  /* b) Volumetric initialization: Ray-casts around mesh object. */
 
   /* Ray-casts in 26 directions.
    * (6 main axis + 12 quadrant diagonals (2D) + 8 octant diagonals (3D)). */
@@ -1508,45 +1508,8 @@ static void update_mesh_distances(int index,
     min_dist = (-1.0f) * fabsf(min_dist);
   }
 
-  /* Update global distance array with distance value. */
-  mesh_distances[index] = min_dist;
-
-  /* b) Volumetric initialization: 2) Use nearest neighbor search on mesh surface. */
-
-  /* Distance between two opposing vertices in a unit cube.
-   * I.e. the unit cube diagonal or sqrt(3).
-   * This value is our nearest neighbour search distance. */
-  const float surface_distance = 1.732;
-  BVHTreeNearest nearest = {0};
-  nearest.index = -1;
-  nearest.dist_sq = surface_distance * surface_distance; /* find_nearest uses squared distance. */
-
-  if (BLI_bvhtree_find_nearest(
-          tree_data->tree, ray_start, &nearest, tree_data->nearest_callback, tree_data) != -1) {
-    float ray[3] = {0};
-    sub_v3_v3v3(ray, nearest.co, ray_start);
-    min_dist = len_v3(ray);
-
-    BVHTreeRayHit hit_tree = {0};
-    hit_tree.index = -1;
-    hit_tree.dist = PHI_MAX;
-
-    normalize_v3(ray);
-    BLI_bvhtree_ray_cast(
-        tree_data->tree, ray_start, ray, 0.0f, &hit_tree, tree_data->raycast_callback, tree_data);
-
-    /* Only proceed if casted ray hit the mesh surface. */
-    if (hit_tree.index != -1) {
-
-      /* Ray and normal are pointing in the same direction: Point must lie inside mesh. */
-      if (dot_v3v3(ray, hit_tree.no) > 0) {
-        min_dist = (-1.0f) * fabsf(min_dist);
-      }
-
-      /* Update distance map with more accurate distance from this nearest neighbor search. */
-      mesh_distances[index] = min_dist;
-    }
-  }
+  /* Update global distance array but ensure that older entries are not overridden. */
+  mesh_distances[index] = MIN2(mesh_distances[index], min_dist);
 
   /* Subtract optional surface thickness value and virtually increase the object size. */
   if (surface_thickness) {