1 files changed, 84 insertions, 0 deletions
diff --git a/source/blender/editors/curves/intern/curves_add.cc b/source/blender/editors/curves/intern/curves_add.cc
index 552ef1d96c8..79916253207 100644
--- a/source/blender/editors/curves/intern/curves_add.cc
+++ b/source/blender/editors/curves/intern/curves_add.cc
@@ -6,12 +6,96 @@
 
 #include "BLI_rand.hh"
 
+#include "BKE_context.h"
 #include "BKE_curves.hh"
+#include "BKE_node.h"
+#include "BKE_node_runtime.hh"
 
 #include "ED_curves.h"
+#include "ED_node.h"
+#include "ED_object.h"
+
+#include "DNA_modifier_types.h"
+#include "DNA_node_types.h"
+#include "DNA_object_types.h"
 
 namespace blender::ed::curves {
 
+static bool has_surface_deformation_node(const bNodeTree &ntree)
+{
+  LISTBASE_FOREACH (const bNode *, node, &ntree.nodes) {
+    if (node->type == GEO_NODE_DEFORM_CURVES_ON_SURFACE) {
+      return true;
+    }
+    if (node->type == NODE_GROUP) {
+      if (node->id != nullptr) {
+        if (has_surface_deformation_node(*reinterpret_cast<const bNodeTree *>(node->id))) {
+          return true;
+        }
+      }
+    }
+  }
+  return false;
+}
+
+static bool has_surface_deformation_node(const Object &curves_ob)
+{
+  LISTBASE_FOREACH (const ModifierData *, md, &curves_ob.modifiers) {
+    if (md->type != eModifierType_Nodes) {
+      continue;
+    }
+    const NodesModifierData *nmd = reinterpret_cast<const NodesModifierData *>(md);
+    if (nmd->node_group == nullptr) {
+      continue;
+    }
+    if (has_surface_deformation_node(*nmd->node_group)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void ensure_surface_deformation_node_exists(bContext &C, Object &curves_ob)
+{
+  if (has_surface_deformation_node(curves_ob)) {
+    return;
+  }
+
+  Main *bmain = CTX_data_main(&C);
+  Scene *scene = CTX_data_scene(&C);
+
+  ModifierData *md = ED_object_modifier_add(
+      nullptr, bmain, scene, &curves_ob, "Surface Deform", eModifierType_Nodes);
+  NodesModifierData &nmd = *reinterpret_cast<NodesModifierData *>(md);
+  nmd.node_group = ntreeAddTree(bmain, "Surface Deform", "GeometryNodeTree");
+
+  bNodeTree *ntree = nmd.node_group;
+  ntreeAddSocketInterface(ntree, SOCK_IN, "NodeSocketGeometry", "Geometry");
+  ntreeAddSocketInterface(ntree, SOCK_OUT, "NodeSocketGeometry", "Geometry");
+  bNode *group_input = nodeAddStaticNode(&C, ntree, NODE_GROUP_INPUT);
+  bNode *group_output = nodeAddStaticNode(&C, ntree, NODE_GROUP_OUTPUT);
+  bNode *deform_node = nodeAddStaticNode(&C, ntree, GEO_NODE_DEFORM_CURVES_ON_SURFACE);
+
+  ED_node_tree_propagate_change(&C, bmain, nmd.node_group);
+
+  nodeAddLink(ntree,
+              group_input,
+              static_cast<bNodeSocket *>(group_input->outputs.first),
+              deform_node,
+              nodeFindSocket(deform_node, SOCK_IN, "Curves"));
+  nodeAddLink(ntree,
+              deform_node,
+              nodeFindSocket(deform_node, SOCK_OUT, "Curves"),
+              group_output,
+              static_cast<bNodeSocket *>(group_output->inputs.first));
+
+  group_input->locx = -200;
+  group_output->locx = 200;
+  deform_node->locx = 0;
+
+  ED_node_tree_propagate_change(&C, bmain, nmd.node_group);
+}
+
 bke::CurvesGeometry primitive_random_sphere(const int curves_size, const int points_per_curve)
 {
   bke::CurvesGeometry curves(points_per_curve * curves_size, curves_size);