Node graph editor basic functionality

9 files changed, 158 insertions, 45 deletions

diff --git a/core/src/Model/Workflow/Nodes/DocumentNodes.cpp b/core/src/Model/Workflow/Nodes/DocumentNodes.cpp
index b858b49..3925dec 100644
--- a/core/src/Model/Workflow/Nodes/DocumentNodes.cpp
+++ b/core/src/Model/Workflow/Nodes/DocumentNodes.cpp
@@ -9,7 +9,7 @@ bool DocumentTemplateExpansionNode::IsInstance(const WorkflowNode* node)
 }
 
 DocumentTemplateExpansionNode::DocumentTemplateExpansionNode()
-	: WorkflowNode(KD_DocumentTemplateExpansion)
+	: WorkflowNode(KD_DocumentTemplateExpansion, false)
 {
 }
 
diff --git a/core/src/Model/Workflow/Nodes/NumericNodes.cpp b/core/src/Model/Workflow/Nodes/NumericNodes.cpp
index 083172e..ad51fb4 100644
--- a/core/src/Model/Workflow/Nodes/NumericNodes.cpp
+++ b/core/src/Model/Workflow/Nodes/NumericNodes.cpp
@@ -36,7 +36,7 @@ bool NumericOperationNode::IsInstance(const WorkflowNode* node)
 }
 
 NumericOperationNode::NumericOperationNode(OperationType type)
-	: WorkflowNode(OperationTypeToNodeKind(type))
+	: WorkflowNode(OperationTypeToNodeKind(type), false)
 	, mType{ type }
 {
 	mInputs.resize(2);
@@ -85,7 +85,7 @@ bool NumericExpressionNode::IsInstance(const WorkflowNode* node)
 }
 
 NumericExpressionNode::NumericExpressionNode()
-	: WorkflowNode(KD_NumericExpression)
+	: WorkflowNode(KD_NumericExpression, false)
 {
 }
 
diff --git a/core/src/Model/Workflow/Nodes/TextNodes.cpp b/core/src/Model/Workflow/Nodes/TextNodes.cpp
index b70290d..6c71309 100644
--- a/core/src/Model/Workflow/Nodes/TextNodes.cpp
+++ b/core/src/Model/Workflow/Nodes/TextNodes.cpp
@@ -53,7 +53,7 @@ bool TextFormatterNode::IsInstance(const WorkflowNode* node)
 }
 
 TextFormatterNode::TextFormatterNode()
-	: WorkflowNode(KD_TextFormatting)
+	: WorkflowNode(KD_TextFormatting, false)
 {
 }
 
diff --git a/core/src/Model/Workflow/Nodes/UserInputNodes.cpp b/core/src/Model/Workflow/Nodes/UserInputNodes.cpp
index 3a30631..f8d3e01 100644
--- a/core/src/Model/Workflow/Nodes/UserInputNodes.cpp
+++ b/core/src/Model/Workflow/Nodes/UserInputNodes.cpp
@@ -9,7 +9,7 @@ bool FormInputNode::IsInstance(const WorkflowNode* node)
 }
 
 FormInputNode::FormInputNode()
-	: WorkflowNode(KD_FormInput)
+	: WorkflowNode(KD_FormInput, false)
 {
 }
 
@@ -23,7 +23,7 @@ bool DatabaseRowsInputNode::IsInstance(const WorkflowNode* node)
 }
 
 DatabaseRowsInputNode::DatabaseRowsInputNode()
-	: WorkflowNode(KD_DatabaseRowsInput)
+	: WorkflowNode(KD_DatabaseRowsInput, false)
 {
 }
 
diff --git a/core/src/Model/Workflow/Workflow.hpp b/core/src/Model/Workflow/Workflow.hpp
index 79c2b2f..847aa72 100644
--- a/core/src/Model/Workflow/Workflow.hpp
+++ b/core/src/Model/Workflow/Workflow.hpp
@@ -4,6 +4,7 @@
 #include "Utils/Vector.hpp"
 #include "cplt_fwd.hpp"
 
+#include <imgui_node_editor.h>
 #include <cstddef>
 #include <cstdint>
 #include <iosfwd>
@@ -14,6 +15,8 @@
 #include <variant>
 #include <vector>
 
+namespace ImNodes = ax::NodeEditor;
+
 class WorkflowConnection
 {
 public:
@@ -31,7 +34,7 @@ public:
 	bool IsValid() const;
 
 	/// Used for `LinkId` when interfacing with imgui node editor. Runtime only (not saved to disk and generated when loading).
-	size_t GetLinkId() const;
+	ImNodes::LinkId GetLinkId() const;
 
 	void DrawDebugInfo() const;
 	void ReadFrom(std::istream& stream);
@@ -99,13 +102,14 @@ protected:
 	uint32_t mId;
 	Kind mKind;
 	int mDepth;
+	bool mLocked;
 
 public:
 	static const char* FormatKind(Kind kind);
 	static const char* FormatType(Type type);
 	static std::unique_ptr<WorkflowNode> CreateByKind(Kind kind);
 
-	WorkflowNode(Kind kind);
+	WorkflowNode(Kind kind, bool locked);
 	virtual ~WorkflowNode() = default;
 
 	WorkflowNode(const WorkflowNode&) = delete;
@@ -118,23 +122,28 @@ public:
 
 	uint32_t GetId() const;
 	/// Used for `NodeId` when interfacing with imgui node editor. Runtime only (not saved to disk and generated when loading).
-	size_t GetNodeId() const;
+	ImNodes::NodeId GetNodeId() const;
 	Kind GetKind() const;
 	int GetDepth() const;
+	bool IsLocked() const;
 
 	Type GetType() const;
 	bool IsInputNode() const;
 	bool IsOutputNode() const;
 
-	void ConnectInput(uint32_t pinId, WorkflowNode& output, uint32_t outputNodeId);
+	void ConnectInput(uint32_t pinId, WorkflowNode& srcNode, uint32_t srcPinId);
 	void DisconnectInput(uint32_t pinId);
+
+	void DrawInputPinDebugInfo(uint32_t pinId) const;
 	const InputPin& GetInputPin(uint32_t pinId)const ;
-	size_t GetInputPinUniqueId(uint32_t pinId) const;
+	ImNodes::PinId GetInputPinUniqueId(uint32_t pinId) const;
 
-	void ConnectOutput(uint32_t pinId, WorkflowNode& input, uint32_t inputNodeId);
+	void ConnectOutput(uint32_t pinId, WorkflowNode& dstNode, uint32_t dstPinId);
 	void DisconnectOutput(uint32_t pinId);
+
+	void DrawOutputPinDebugInfo(uint32_t pinId)const;
 	const OutputPin& GetOutputPin(uint32_t pinId)const ;
-	size_t GetOutputPinUniqueId(uint32_t pinId) const;
+	ImNodes::PinId GetOutputPinUniqueId(uint32_t pinId) const;
 
 	virtual void Evaluate(WorkflowEvaluationContext& ctx) = 0;
 
@@ -187,7 +196,9 @@ public:
 	std::vector<std::unique_ptr<BaseValue>>& GetConstants();
 
 	WorkflowConnection* GetConnectionById(uint32_t id);
+	WorkflowConnection* GetConnectionByLinkId(ImNodes::LinkId linkId);
 	WorkflowNode* GetNodeById(uint32_t id);
+	WorkflowNode* GetNodeByNodeId(ImNodes::NodeId nodeId);
 	BaseValue* GetConstantById(uint32_t id);
 
 	struct GlobalPinId
@@ -200,8 +211,8 @@ public:
 	};
 
 	/// `pinId` should be the `UniqueId` of a pin from a node that's within this workflow.
-	GlobalPinId DisassembleGlobalPinId(size_t id);
-	size_t FabricateGlobalPinId(const WorkflowNode& node, uint32_t pinId, bool isOutput) const;
+	GlobalPinId DisassembleGlobalPinId(ImNodes::PinId id);
+	ImNodes::PinId FabricateGlobalPinId(const WorkflowNode& node, uint32_t pinId, bool isOutput) const;
 
 	const std::vector<std::vector<uint32_t>>& GetDepthGroups() const;
 	bool DoesDepthNeedsUpdate() const;
diff --git a/core/src/Model/Workflow/Workflow_Main.cpp b/core/src/Model/Workflow/Workflow_Main.cpp
index 678b4b8..1b50064 100644
--- a/core/src/Model/Workflow/Workflow_Main.cpp
+++ b/core/src/Model/Workflow/Workflow_Main.cpp
@@ -24,7 +24,7 @@ bool WorkflowConnection::IsValid() const
 	return Id != 0;
 }
 
-size_t WorkflowConnection::GetLinkId() const
+ImNodes::LinkId WorkflowConnection::GetLinkId() const
 {
 	// Our id is 0-based (represents an index directly)
 	// but imgui-node-editor uses the value 0 to represent a null id, so we need to offset by 1
@@ -33,12 +33,10 @@ size_t WorkflowConnection::GetLinkId() const
 
 void WorkflowConnection::DrawDebugInfo() const
 {
-	ImGui::BeginTooltip();
 	ImGui::Text("Source (node with output pin):");
 	ImGui::Text("{ Node = %u, Pin = %u }", SourceNode, SourcePin);
 	ImGui::Text("Destination (node with input pin):");
 	ImGui::Text("{ Node = %u, Pin = %u }", DestinationNode, DestinationPin);
-	ImGui::EndTooltip();
 }
 
 void WorkflowConnection::ReadFrom(std::istream& stream)
@@ -78,9 +76,10 @@ BaseValue::Kind WorkflowNode::OutputPin::GetMatchingType() const
 	return MatchingType;
 }
 
-WorkflowNode::WorkflowNode(Kind kind)
+WorkflowNode::WorkflowNode(Kind kind, bool locked)
 	: mKind{ kind }
 	, mDepth{ -1 }
+	, mLocked(locked)
 {
 }
 
@@ -99,7 +98,7 @@ uint32_t WorkflowNode::GetId() const
 	return mId;
 }
 
-size_t WorkflowNode::GetNodeId() const
+ImNodes::NodeId WorkflowNode::GetNodeId() const
 {
 	// See WorkflowConnection::GetLinkId for the rationale
 	return mId + 1;
@@ -115,6 +114,11 @@ int WorkflowNode::GetDepth() const
 	return mDepth;
 }
 
+bool WorkflowNode::IsLocked() const
+{
+	return mLocked;
+}
+
 WorkflowNode::Type WorkflowNode::GetType() const
 {
 	if (IsInputNode()) {
@@ -136,9 +140,9 @@ bool WorkflowNode::IsOutputNode() const
 	return mOutputs.size() == 0;
 }
 
-void WorkflowNode::ConnectInput(uint32_t pinId, WorkflowNode& output, uint32_t outputNodeId)
+void WorkflowNode::ConnectInput(uint32_t pinId, WorkflowNode& srcNode, uint32_t srcPinId)
 {
-	mWorkflow->Connect(*this, pinId, output, outputNodeId);
+	mWorkflow->Connect(*this, pinId, srcNode, srcPinId);
 }
 
 void WorkflowNode::DisconnectInput(uint32_t pinId)
@@ -146,19 +150,25 @@ void WorkflowNode::DisconnectInput(uint32_t pinId)
 	mWorkflow->DisconnectByDestination(*this, pinId);
 }
 
+void WorkflowNode::DrawInputPinDebugInfo(uint32_t pinId) const
+{
+	ImGui::Text("Node ID: %d", mId);
+	ImGui::Text("Pin ID: (input) %d", pinId);
+}
+
 const WorkflowNode::InputPin& WorkflowNode::GetInputPin(uint32_t pinId) const
 {
 	return mInputs[pinId];
 }
 
-size_t WorkflowNode::GetInputPinUniqueId(uint32_t pinId) const
+ImNodes::PinId WorkflowNode::GetInputPinUniqueId(uint32_t pinId) const
 {
 	return mWorkflow->FabricateGlobalPinId(*this, pinId, false);
 }
 
-void WorkflowNode::ConnectOutput(uint32_t pinId, WorkflowNode& input, uint32_t inputNodeId)
+void WorkflowNode::ConnectOutput(uint32_t pinId, WorkflowNode& dstNode, uint32_t dstPinId)
 {
-	mWorkflow->Connect(input, inputNodeId, *this, pinId);
+	mWorkflow->Connect(dstNode, dstPinId, *this, pinId);
 }
 
 void WorkflowNode::DisconnectOutput(uint32_t pinId)
@@ -166,12 +176,18 @@ void WorkflowNode::DisconnectOutput(uint32_t pinId)
 	mWorkflow->DisconnectBySource(*this, pinId);
 }
 
+void WorkflowNode::DrawOutputPinDebugInfo(uint32_t pinId) const
+{
+	ImGui::Text("Node ID: %d", mId);
+	ImGui::Text("Pin ID: (output) %d", pinId);
+}
+
 const WorkflowNode::OutputPin& WorkflowNode::GetOutputPin(uint32_t pinId) const
 {
 	return mOutputs[pinId];
 }
 
-size_t WorkflowNode::GetOutputPinUniqueId(uint32_t pinId) const
+ImNodes::PinId WorkflowNode::GetOutputPinUniqueId(uint32_t pinId) const
 {
 	return mWorkflow->FabricateGlobalPinId(*this, pinId, true);
 }
@@ -180,12 +196,14 @@ void WorkflowNode::Draw()
 {
 	for (uint32_t i = 0; i < mInputs.size(); ++i) {
 		auto& pin = mInputs[i];
+		auto& typeInfo = BaseValue::QueryInfo(pin.MatchingType);
 		ImNodes::BeginPin(GetInputPinUniqueId(i), ImNodes::PinKind::Input);
 		// TODO
 		ImNodes::EndPin();
 	}
 	for (uint32_t i = 0; i < mOutputs.size(); ++i) {
 		auto& pin = mOutputs[i];
+		auto& typeInfo = BaseValue::QueryInfo(pin.MatchingType);
 		ImNodes::BeginPin(GetOutputPinUniqueId(i), ImNodes::PinKind::Output);
 		// TODO
 		ImNodes::EndPin();
@@ -194,13 +212,11 @@ void WorkflowNode::Draw()
 
 void WorkflowNode::DrawDebugInfo() const
 {
-	ImGui::BeginTooltip();
 	ImGui::Text("Node kind: %s", FormatKind(mKind));
 	ImGui::Text("Node type: %s", FormatType(GetType()));
 	ImGui::Text("Node ID: %u", mId);
 	ImGui::Text("Depth: %d", mDepth);
 	DrawExtraDebugInfo();
-	ImGui::EndTooltip();
 }
 
 void WorkflowNode::ReadFrom(std::istream& stream)
@@ -338,17 +354,27 @@ WorkflowConnection* Workflow::GetConnectionById(uint32_t id)
 	return &mConnections[id];
 }
 
+WorkflowConnection* Workflow::GetConnectionByLinkId(ImNodes::LinkId id)
+{
+	return &mConnections[(uint32_t)(size_t)id - 1];
+}
+
 WorkflowNode* Workflow::GetNodeById(uint32_t id)
 {
 	return mNodes[id].get();
 }
 
+WorkflowNode* Workflow::GetNodeByNodeId(ImNodes::NodeId id)
+{
+	return mNodes[(uint32_t)(size_t)id - 1].get();
+}
+
 BaseValue* Workflow::GetConstantById(uint32_t id)
 {
 	return mConstants[id].get();
 }
 
-Workflow::GlobalPinId Workflow::DisassembleGlobalPinId(size_t id)
+Workflow::GlobalPinId Workflow::DisassembleGlobalPinId(ImNodes::PinId pinId)
 {
 	// imgui-node-editor requires all pins to have a global, unique id
 	// but in our model the pin are typed (input vs output) and associated with a node: there is no built-in global id
@@ -362,6 +388,7 @@ Workflow::GlobalPinId Workflow::DisassembleGlobalPinId(size_t id)
 	// 1 is added to pin id to prevent the 0th node's 0th input pin resulting in a 0 global pin id
 	// (this is problematic because imgui-node-editor use 0 to represent null)
 
+	auto id = static_cast<uint64_t>(pinId);
 	GlobalPinId result;
 
 	result.Node = mNodes[id >> 32].get();
@@ -371,7 +398,7 @@ Workflow::GlobalPinId Workflow::DisassembleGlobalPinId(size_t id)
 	return result;
 }
 
-size_t Workflow::FabricateGlobalPinId(const WorkflowNode& node, uint32_t pinId, bool isOutput) const
+ImNodes::PinId Workflow::FabricateGlobalPinId(const WorkflowNode& node, uint32_t pinId, bool isOutput) const
 {
 	// See this->DisassembleGlobalPinId for format details and rationale
 
diff --git a/core/src/UI/Localization.hpp b/core/src/UI/Localization.hpp
index 65fcdfd..b421d24 100644
--- a/core/src/UI/Localization.hpp
+++ b/core/src/UI/Localization.hpp
@@ -19,6 +19,7 @@ public:
 	BasicTranslation Add{ "Generic.Add"sv };
 	BasicTranslation Edit{ "Generic.Edit"sv };
 	BasicTranslation Delete{ "Generic.Delete"sv };
+	BasicTranslation Disconnect{ "Generic.Disconnect"sv };
 	BasicTranslation Close{ "Generic.Close"sv };
 	BasicTranslation DialogConfirm{ "Generic.Dialog.Confirm"sv };
 	BasicTranslation DialogCancel{ "Generic.Dialog.Cancel"sv };
diff --git a/core/src/UI/UI_Workflows.cpp b/core/src/UI/UI_Workflows.cpp
index 7aefeab..1a4294f 100644
--- a/core/src/UI/UI_Workflows.cpp
+++ b/core/src/UI/UI_Workflows.cpp
@@ -138,6 +138,10 @@ private:
 	ImNodes::EditorContext* mContext;
 	WorkflowDatabase mWorkflowDatabase;
 
+	ImNodes::NodeId mContextMenuNodeId = 0;
+	ImNodes::PinId mContextMenuPinId = 0;
+	ImNodes::LinkId mContextMenuLinkId = 0;
+
 public:
 	WorkflowUI()
 	{
@@ -152,9 +156,12 @@ public:
 
 	void Draw()
 	{
+		auto ls = LocaleStrings::Instance.get();
+
 		ImNodes::SetCurrentEditor(mContext);
 		ImNodes::Begin("");
 
+		// Defer creation of tooltip because within the node editor, cursor positioning is going to be off
 		const char* tooltipMessage = nullptr;
 
 		for (auto& node : mWorkflow->GetNodes()) {
@@ -180,8 +187,8 @@ public:
 					goto createError;
 				}
 
-				auto [srcNode, srcPinId, srcIsOutput] = mWorkflow->DisassembleGlobalPinId((size_t)src);
-				auto [dstNode, dstPinId, dstIsOutput] = mWorkflow->DisassembleGlobalPinId((size_t)dst);
+				auto [srcNode, srcPinId, srcIsOutput] = mWorkflow->DisassembleGlobalPinId(src);
+				auto [dstNode, dstPinId, dstIsOutput] = mWorkflow->DisassembleGlobalPinId(dst);
 
 				if (srcNode == dstNode) {
 					ImNodes::RejectNewItem();
@@ -208,7 +215,7 @@ public:
 
 			ImNodes::PinId newNodePin = 0;
 			if (ImNodes::QueryNewNode(&newNodePin)) {
-				auto [node, pinId, isOutput] = mWorkflow->DisassembleGlobalPinId((size_t)newNodePin);
+				auto [node, pinId, isOutput] = mWorkflow->DisassembleGlobalPinId(newNodePin);
 
 				if ((isOutput && node->GetOutputPin(pinId).IsConnected()) ||
 					(!isOutput && node->GetInputPin(pinId).IsConnected()))
@@ -230,10 +237,22 @@ public:
 		if (ImNodes::BeginDelete()) {
 			ImNodes::LinkId deletedLinkId;
 			if (ImNodes::QueryDeletedLink(&deletedLinkId)) {
-				// Link id is the same as our connection id
-				auto& conn = *mWorkflow->GetConnectionById((size_t)deletedLinkId);
+				auto& conn = *mWorkflow->GetConnectionByLinkId(deletedLinkId);
+				mWorkflow->RemoveConnection(conn.Id);
+			}
+
+			ImNodes::NodeId deletedNodeId;
+			if (ImNodes::QueryDeletedNode(&deletedNodeId)) {
+				auto node = mWorkflow->GetNodeByNodeId(deletedNodeId);
+				if (!node) {
+					ImNodes::RejectDeletedItem();
+					goto deleteError;
+				}
 
-				// TODO
+				if (node->IsLocked()) {
+					ImNodes::RejectDeletedItem();
+					goto deleteError;
+				}
 			}
 		}
 	deleteError:
@@ -241,23 +260,77 @@ public:
 
 		// Popups
 		ImNodes::Suspend();
+		if (ImNodes::ShowNodeContextMenu(&mContextMenuNodeId)) {
+			ImGui::OpenPopup("Node Context Menu");
+		} else if (ImNodes::ShowPinContextMenu(&mContextMenuPinId)) {
+			ImGui::OpenPopup("Pin Context Menu");
+		} else if (ImNodes::ShowLinkContextMenu(&mContextMenuLinkId)) {
+			ImGui::OpenPopup("Link Context Menu");
+		}
+
 		if (ImGui::BeginPopup("Node Context Menu")) {
-			// TODO
+			auto& node = *mWorkflow->GetNodeByNodeId(mContextMenuNodeId);
+			node.DrawDebugInfo();
+
+			if (ImGui::MenuItem(ls->Delete.Get())) {
+				ImNodes::DeleteNode(mContextMenuNodeId);
+			}
+
 			ImGui::EndPopup();
 		}
+
+		if (ImGui::BeginPopup("Pin Context Menu")) {
+			auto [node, pinId, isOutput] = mWorkflow->DisassembleGlobalPinId(mContextMenuPinId);
+			if (isOutput) {
+				node->DrawOutputPinDebugInfo(pinId);
+			} else {
+				node->DrawInputPinDebugInfo(pinId);
+			}
+
+			if (ImGui::MenuItem(ls->Disconnect.Get())) {
+				if (isOutput) {
+					auto& pin = node->GetOutputPin(pinId);
+					if (pin.IsConnected()) {
+						auto linkId = mWorkflow->GetConnectionById(pin.Connection)->GetLinkId();
+						ImNodes::DeleteLink(linkId);
+					}
+				} else {
+					auto& pin = node->GetInputPin(pinId);
+					if (pin.IsConstantConnection()) {
+						// TODO
+					} else if (pin.IsConnected()) {
+						auto linkId = mWorkflow->GetConnectionById(pin.Connection)->GetLinkId();
+						ImNodes::DeleteLink(linkId);
+					}
+				}
+			}
+
+			ImGui::EndPopup();
+		}
+
 		if (ImGui::BeginPopup("Link Context Menu")) {
-			// TODO
+			auto& conn = *mWorkflow->GetConnectionByLinkId(mContextMenuLinkId);
+			conn.DrawDebugInfo();
+
+			if (ImGui::MenuItem(ls->Delete.Get())) {
+				ImNodes::DeleteLink(mContextMenuLinkId);
+			}
+
 			ImGui::EndPopup();
 		}
+
 		if (ImGui::BeginPopup("Create Node")) {
 			auto DisplayCandidatesCategory = [&](const char* name, std::span<const WorkflowDatabase::Candidate> candidates) {
-				ImGui::TreeNode(name);
-				for (auto& candidate : candidates) {
-					if (ImGui::MenuItem(candidate.Name.c_str())) {
-						// TODO
+				if (ImGui::BeginMenu(name)) {
+					for (auto& candidate : candidates) {
+						if (ImGui::MenuItem(candidate.Name.c_str())) {
+							// Create node
+							auto uptr = candidate.Constructor();
+							mWorkflow->AddNode(std::move(uptr));
+						}
 					}
+					ImGui::EndMenu();
 				}
-				ImGui::TreePop();
 			};
 
 			DisplayCandidatesCategory("Numeric nodes", mWorkflowDatabase.GetNumericNodes());
@@ -268,6 +341,7 @@ public:
 			DisplayCandidatesCategory("Output nodes", mWorkflowDatabase.GetOutputNodes());
 			ImGui::EndPopup();
 		}
+
 		if (tooltipMessage) {
 			ImGui::BeginTooltip();
 			ImGui::TextUnformatted(tooltipMessage);
diff --git a/core/src/Utils/Color.hpp b/core/src/Utils/Color.hpp
index 26cfdd4..5f4691f 100644
--- a/core/src/Utils/Color.hpp
+++ b/core/src/Utils/Color.hpp
@@ -164,8 +164,8 @@ constexpr HsvColor RgbaColor::ToHsv() const noexcept
 	float fb = GetNormalizedGreen();

 	float fa = GetNormalizedAlpha();

 

-	auto p = fg < fb ? ImVec4(fb, fg, -1, 2.0f / 3.0f) : ImVec4(fg, fb, 0, -1.0f / 3.0f);

-	auto q = fr < p.x ? ImVec4(p.x, p.y, p.w, fr) : ImVec4(fr, p.y, p.z, p.x);

+	auto p = fg < fb ? Vec4f{ fb, fg, -1, 2.0f / 3.0f } : Vec4f{ fg, fb, 0, -1.0f / 3.0f };

+	auto q = fr < p.x ? Vec4f{ p.x, p.y, p.w, fr } : Vec4f{ fr, p.y, p.z, p.x };

 	float c = q.x - std::min(q.w, q.y);

 	float h = std::abs((q.w - q.y) / (6 * c + std::numeric_limits<float>::epsilon()) + q.z);