✨ [Nodes] Show description of inputs next to the pin

Allows to show the description of Input Functions somewhere, and adds a second place to see description of Input Values

src/Cool/ImGui/ImGuiExtras.cpp

@@ -17,16 +17,26 @@ namespace Cool::ImGuiExtras {
 void help_marker(const char* text)
 {
     ImGui::SameLine();
-    ImGui::TextDisabled(" " ICOMOON_INFO);
+    help_marker_icon();
     if (ImGui::BeginItemTooltip())
     {
-        ImGui::PushTextWrapPos(ImGui::GetFontSize() * 35.f);
-        ImGui::TextUnformatted(text);
-        ImGui::PopTextWrapPos();
+        help_marker_tooltip_content(text);
         ImGui::EndTooltip();
     }
 }
 
+void help_marker_icon()
+{
+    ImGui::TextDisabled(" " ICOMOON_INFO);
+}
+
+void help_marker_tooltip_content(const char* text)
+{
+    ImGui::PushTextWrapPos(ImGui::GetFontSize() * 35.f);
+    ImGui::TextUnformatted(text);
+    ImGui::PopTextWrapPos();
+}
+
 bool angle_wheel(const char* label, float* value_p, int number_of_snaps, float snaps_offset, bool always_snap)
 {
     static constexpr float thickness = 2.0f;

src/Cool/ImGui/ImGuiExtras.h

@@ -6,9 +6,14 @@
 
 namespace Cool::ImGuiExtras {
 
-/// A small "?" that displays some text when hovered.
+/// A small info icon that displays some text when hovered.
 void help_marker(const char* text);
 
+/// A building block for help_marker(). In most cases you should just use help_marker(). This is only needed when you need to customize how help_marker() is rendered.
+void help_marker_icon();
+/// A building block for help_marker(). In most cases you should just use help_marker(). This is only needed when you need to customize how help_marker() is rendered.
+void help_marker_tooltip_content(const char* text);
+
 /// A widget to pick an angle (in radians), displayed as a direction on a wheel
 /// When SHIFT is pressed (or `always_snap` is set to true) the angle will snap to some precise angles. `number_of_snaps` controls the number of such angles, and `snaps_offset` will offset these.
 /// `number_of_snaps` must be >= 1. `snaps_offset` is expressed in radians.

src/Cool/Nodes/EditorImpl.cpp

@@ -5,6 +5,7 @@
 #include "Cool/DebugOptions/DebugOptions.h"
 #include "Cool/ImGui/Fonts.h"
 #include "Cool/ImGui/IcoMoonCodepoints.h"
+#include "Cool/ImGui/ImGuiExtras.h"
 #include "Cool/ImGui/ImGuiExtrasStyle.h"
 #include "Cool/ImGui/icon_fmt.h"
 #include "Cool/Nodes/EditorImpl.h"
@@ -324,6 +325,13 @@ static auto output_pin_icon(size_t pin_index)
                : ax::Drawing::IconType::Circle;
 }
 
+void NodesEditorImpl::help_marker_for_pin(std::string text)
+{
+    ImGuiExtras::help_marker_icon();
+    if (ImGui::IsItemHovered(ImGuiHoveredFlags_ForTooltip))
+        _deferred_tooltip_text = std::move(text); // HACK don't create the tooltip here, because imgui-node-editor doesn't support it (even when calling Suspend() and Resume()) because of a bug (https://github.com/thedmd/imgui-node-editor/issues/282)
+}
+
 void NodesEditorImpl::render_node(Node& node, NodeId const& id, NodesConfig& nodes_cfg, NodesLibrary const& library, ax::NodeEditor::Utilities::BlueprintNodeBuilder& builder)
 {
     auto const  color       = nodes_cfg.node_color(node, id);
@@ -375,6 +383,11 @@ void NodesEditorImpl::render_node(Node& node, NodeId const& id, NodesConfig& nod
             ImGui::TextUnformatted(input_pin.name().c_str());
             ImGui::Spring(0);
         }
+        if (!input_pin.description().empty())
+        {
+            help_marker_for_pin(input_pin.description());
+            ImGui::Spring(0);
+        }
         ImGui::PopStyleVar();
         builder.EndInput();
     }
@@ -392,6 +405,11 @@ void NodesEditorImpl::render_node(Node& node, NodeId const& id, NodesConfig& nod
             ImGui::Spring(0);
             ImGui::TextUnformatted(output_pin.name().c_str());
         }
+        if (!output_pin.description().empty())
+        {
+            ImGui::Spring(0);
+            help_marker_for_pin(output_pin.description());
+        }
         ImGui::Spring(0);
         render_pin_icon(output_pin_icon(idx), alpha, nodes_cfg.pin_color(output_pin, idx, node, id));
         ImGui::PopStyleVar();
@@ -711,11 +729,9 @@ auto NodesEditorImpl::imgui_workspace(NodesConfig& nodes_cfg, NodesLibrary const
     }
 
     bool graph_has_changed = false;
+    _deferred_tooltip_text.reset(); // Might be filled by one of the nodes, and will be rendered later
 
     ed::SetCurrentEditor(_context);
-    // GImGui->CurrentWindow->DrawList->AddRectFilled(ImVec2{0.f, 0.f}, ImVec2{0.f, 0.f},  ImGui::GetColorU32(ImGuiCol_SeparatorHovered), 0.0f); // TODO(JF) Remove this. (But atm when removing it the view gets clipped when zooming in) EDIT this is caused by the suspend / resume
-    GImGui->CurrentWindow->DrawList->AddLine(ImVec2{0.f, 0.f}, ImVec2{0.f, 0.f}, ImGui::GetColorU32(ImGuiCol_SeparatorHovered)); // TODO(JF) Remove this. (But atm when removing it the view gets clipped when zooming in) EDIT this is caused by the suspend / resume
-
     ed::Begin("Node editor");
 
     render_editor(nodes_cfg, library);
@@ -740,6 +756,11 @@ auto NodesEditorImpl::imgui_workspace(NodesConfig& nodes_cfg, NodesLibrary const
     }
 
     ed::Suspend();
+    if (_deferred_tooltip_text.has_value() && ImGui::BeginTooltip())
+    {
+        ImGuiExtras::help_marker_tooltip_content(_deferred_tooltip_text->c_str());
+        ImGui::EndTooltip();
+    }
     if (ImGui::BeginPopup("Nodes Library Menu"))
     {
         auto const new_node_def_id = imgui_nodes_menu(library, nodes_cfg.maybe_disable_node_definition(), _menu_just_opened);

src/Cool/Nodes/EditorImpl.h

@@ -74,6 +74,7 @@ class NodesEditorImpl : public INodesEditor {
     auto wants_to_open_nodes_menu() const -> bool;
     void open_nodes_menu();
     void remove_all_links_connected_to_input_pin(PinId const& input_pin_id, NodesConfig& nodes_cfg);
+    void help_marker_for_pin(std::string text);
 
 private:
     internal::UniqueEdContext        _context{};
@@ -88,7 +89,8 @@ class NodesEditorImpl : public INodesEditor {
     Pin const*                       _new_link_pin            = nullptr;
     bool                             _link_has_just_been_released{false}; // HACK because we can't open the nodes menu just after a link has been released (otherwise _next_node_position is wrong). So we have to delay the opening.
 
-    int _frames_count{0};
+    int                        _frames_count{0};
+    std::optional<std::string> _deferred_tooltip_text{};
 
 private:
     // ImColor GetIconColor(PinType type);

src/Cool/Nodes/Pin.cpp

@@ -2,8 +2,9 @@
 
 namespace Cool {
 
-Pin::Pin(std::string_view name)
-    : _name{name}
+Pin::Pin(std::string name, std::string description)
+    : _name{std::move(name)}
+    , _description{std::move(description)}
     , _id{reg::internal::generate_uuid()}
 {
 }

src/Cool/Nodes/Pin.h

@@ -17,14 +17,15 @@ enum class PinKind {
 class Pin {
 public:
     Pin() = default;
-    explicit Pin(std::string_view name);
+    Pin(std::string name, std::string description);
     Pin(Pin const&)                    = default;
     Pin(Pin&&)                         = default;
     auto operator=(Pin const&) -> Pin& = default;
     auto operator=(Pin&&) -> Pin&      = default;
     virtual ~Pin()                     = default;
 
     [[nodiscard]] auto name() const -> std::string const& { return _name; }
+    [[nodiscard]] auto description() const -> std::string const& { return _description; }
     [[nodiscard]] auto id() const -> PinId const& { return _id; }
 
     void set_id(PinId const& id) { _id = id; }
@@ -36,6 +37,7 @@ class Pin {
 
 private:
     std::string _name{};
+    std::string _description{};
     PinId       _id{};
 
 private:
@@ -46,6 +48,7 @@ class Pin {
     {
         archive(
             cereal::make_nvp("Name", _name),
+            cereal::make_nvp("Description", _description),
             cereal::make_nvp("ID", _id)
         );
     }