[Bf-blender-cvs] [ef45399f3be] master: Nodes: initial support for socket tooltips

[Johnny Matthews]

Commit: ef45399f3be0955ba8a8c678a5f5ed18ed8c7759
Author: Johnny Matthews
Date:   Fri Sep 24 17:02:51 2021 +0200
Branches: master
https://developer.blender.org/rBef45399f3be0955ba8a8c678a5f5ed18ed8c7759

Nodes: initial support for socket tooltips

This adds initial limited support for socket tooltips. It's limited
in a couple of ways for now:
* Only works when hovering over the socket shape, not when hovering
  over the value in the socket.
* Only works for built-in nodes that already use the new node
  declaration system. This can later be extended to support pynodes.

Those limitations are well worth it for now, given that the
implementation is quite simple and the impact on usability is quite
large. More complex updates to the layout system, that would allow
showing socket tooltips in the nodes, can be done later. With the
current implementation we can at least start writing tooltips for
geometry nodes now.

This commit already adds tooltips for the Cylinder node as an example.

Differential Revision: https://developer.blender.org/D12607

===================================================================

M	source/blender/editors/space_node/node_draw.cc
M	source/blender/nodes/NOD_node_declaration.hh
M	source/blender/nodes/geometry/nodes/node_geo_mesh_primitive_cylinder.cc

===================================================================

diff --git a/source/blender/editors/space_node/node_draw.cc b/source/blender/editors/space_node/node_draw.cc
index b57696cb676..499ccb8a889 100644
--- a/source/blender/editors/space_node/node_draw.cc
+++ b/source/blender/editors/space_node/node_draw.cc
@@ -79,6 +79,7 @@
 #include "RNA_access.h"
 
 #include "NOD_geometry_nodes_eval_log.hh"
+#include "NOD_node_declaration.hh"
 
 #include "FN_field_cpp_type.hh"
 
@@ -1085,12 +1086,37 @@ static void node_socket_draw_nested(const bContext *C,
       but,
       [](bContext *C, void *argN, const char *UNUSED(tip)) {
         SocketTooltipData *data = (SocketTooltipData *)argN;
-        std::optional<std::string> str = create_socket_inspection_string(
+        std::optional<std::string> socket_inspection_str = create_socket_inspection_string(
             C, *data->ntree, *data->node, *data->socket);
-        if (str.has_value()) {
-          return BLI_strdup(str->c_str());
+
+        std::stringstream output;
+        if (data->node->declaration != nullptr) {
+          ListBase *list;
+          Span<blender::nodes::SocketDeclarationPtr> decl_list;
+
+          if (data->socket->in_out == SOCK_IN) {
+            list = &data->node->inputs;
+            decl_list = data->node->declaration->inputs();
+          }
+          else {
+            list = &data->node->outputs;
+            decl_list = data->node->declaration->outputs();
+          }
+
+          const int socket_index = BLI_findindex(list, data->socket);
+          const blender::nodes::SocketDeclaration &socket_decl = *decl_list[socket_index];
+          blender::StringRef description = socket_decl.description();
+          if (!description.is_empty()) {
+            output << TIP_(description.data()) << ".\n\n";
+          }
+
+          if (socket_inspection_str.has_value()) {
+            output << *socket_inspection_str;
+            return BLI_strdup(output.str().c_str());
+          }
         }
-        return BLI_strdup(TIP_("The socket value has not been computed yet"));
+        output << TIP_("The socket value has not been computed yet");
+        return BLI_strdup(output.str().c_str());
       },
       data,
       MEM_freeN);
diff --git a/source/blender/nodes/NOD_node_declaration.hh b/source/blender/nodes/NOD_node_declaration.hh
index 6780dfcad59..8c7d343c001 100644
--- a/source/blender/nodes/NOD_node_declaration.hh
+++ b/source/blender/nodes/NOD_node_declaration.hh
@@ -119,6 +119,7 @@ class SocketDeclaration {
  protected:
   std::string name_;
   std::string identifier_;
+  std::string description_;
   bool hide_label_ = false;
   bool hide_value_ = false;
   bool is_multi_input_ = false;
@@ -138,6 +139,7 @@ class SocketDeclaration {
   virtual bNodeSocket &update_or_build(bNodeTree &ntree, bNode &node, bNodeSocket &socket) const;
 
   StringRefNull name() const;
+  StringRefNull description() const;
   StringRefNull identifier() const;
 
   InputSocketFieldType input_field_type() const;
@@ -186,6 +188,11 @@ class SocketDeclarationBuilder : public BaseSocketDeclarationBuilder {
     return *(Self *)this;
   }
 
+  Self &description(std::string value = "")
+  {
+    decl_->description_ = std::move(value);
+    return *(Self *)this;
+  }
   Self &no_muted_links(bool value = true)
   {
     decl_->no_mute_links_ = value;
@@ -297,6 +304,10 @@ inline StringRefNull SocketDeclaration::identifier() const
   return identifier_;
 }
 
+inline StringRefNull SocketDeclaration::description() const
+{
+  return description_;
+}
 inline InputSocketFieldType SocketDeclaration::input_field_type() const
 {
   return input_field_type_;
diff --git a/source/blender/nodes/geometry/nodes/node_geo_mesh_primitive_cylinder.cc b/source/blender/nodes/geometry/nodes/node_geo_mesh_primitive_cylinder.cc
index ed701c921ca..8c4defc3ca3 100644
--- a/source/blender/nodes/geometry/nodes/node_geo_mesh_primitive_cylinder.cc
+++ b/source/blender/nodes/geometry/nodes/node_geo_mesh_primitive_cylinder.cc
@@ -29,9 +29,21 @@ namespace blender::nodes {
 
 static void geo_node_mesh_primitive_cylinder_declare(NodeDeclarationBuilder &b)
 {
-  b.add_input<decl::Int>("Vertices").default_value(32).min(3).max(4096);
-  b.add_input<decl::Float>("Radius").default_value(1.0f).min(0.0f).subtype(PROP_DISTANCE);
-  b.add_input<decl::Float>("Depth").default_value(2.0f).min(0.0f).subtype(PROP_DISTANCE);
+  b.add_input<decl::Int>("Vertices")
+      .default_value(32)
+      .min(3)
+      .max(4096)
+      .description("The number of vertices around the circumference");
+  b.add_input<decl::Float>("Radius")
+      .default_value(1.0f)
+      .min(0.0f)
+      .subtype(PROP_DISTANCE)
+      .description("The radius of the cylinder");
+  b.add_input<decl::Float>("Depth")
+      .default_value(2.0f)
+      .min(0.0f)
+      .subtype(PROP_DISTANCE)
+      .description("The height of the cylinder on the Z axis");
   b.add_output<decl::Geometry>("Geometry");
 }