DockTree.h

浏览该文件的文档.

#pragma once
 
#include <cstdint>
#include <memory>
#include <string>
#include <vector>
 
namespace z8::ui {
class BaseNode;
 
using DockNodeID = std::uint64_t;
 
struct DockRect {
  float Left = 0.0f;
  float Top = 0.0f;
  float Width = 0.0f;
  float Height = 0.0f;
 
  bool Contains(float x, float y) const;
};
 
enum class DockNodeType { Leaf, Split };
enum class SplitAxis { Horizontal, Vertical };
enum class FixedSplitChild { None, A, B };
enum class DockSide { Left, Right, Top, Bottom, Center };
enum class PanelPlacement { Docked, Floating };
 
struct DockNode {
  DockNodeID ID = 0;
  DockNodeType Type = DockNodeType::Leaf;
  DockNode *Parent = nullptr;
  DockRect Rect;
  SplitAxis Axis = SplitAxis::Vertical;
  float SplitRatio = 0.5f;
  float FixedExtent = 0.0f;
  FixedSplitChild FixedChild = FixedSplitChild::None;
  bool SplitterResizable = true;
  std::unique_ptr<DockNode> ChildA;
  std::unique_ptr<DockNode> ChildB;
  std::vector<BaseNode *> Panels;
};
 
struct DockTransaction {
  BaseNode *Panel = nullptr;
  DockNodeID SourceNode = 0;
  DockNodeID TargetNode = 0;
  DockSide TargetSide = DockSide::Center;
  bool TargetFloating = false;
  DockRect FloatingRect;
  float SplitRatio = 0.5f;
  float FixedExtent = 0.0f;
  bool SplitterResizable = true;
};
 
class DockTree final {
public:
  std::unique_ptr<DockNode> Root;
 
  DockNode *AddPanel(BaseNode *panel);
  bool Commit(const DockTransaction &transaction);
  DockNode *Find(DockNodeID id) const;
  DockNode *FindLeafAt(float x, float y) const;
  DockNode *FindPanelLeaf(const BaseNode *panel) const;
  DockNode *FindSplitterAt(float x, float y, float tolerance = 4.0f) const;
  DockRect GetPreviewRect(const DockNode &target, DockSide side) const;
  void Layout(const DockRect &workspace);
  bool RemovePanel(BaseNode *panel);
  bool ResizeSplitter(DockNodeID split, float clientX, float clientY,
                      float minimumExtent = 80.0f);
  bool Validate(std::string *error = nullptr) const;
  std::string Dump() const;
  void Clear();
 
private:
  DockNodeID NextID = 1;
 
  std::unique_ptr<DockNode> CreateLeaf(BaseNode *panel = nullptr);
  void CollapseEmptyLeaf(DockNodeID leaf);
  static void LayoutNode(DockNode &node, const DockRect &rect);
  std::unique_ptr<DockNode> *OwnerSlot(DockNode *node);
};
 
} // namespace z8::ui