internal: Remake borders as window decorations (#4104)

src/render/decorations/CHyprBorderDecoration.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "IHyprWindowDecoration.hpp"
+
+class CHyprBorderDecoration : public IHyprWindowDecoration {
+  public:
+    CHyprBorderDecoration(CWindow*);
+    virtual ~CHyprBorderDecoration();
+
+    virtual SDecorationPositioningInfo getPositioningInfo();
+
+    virtual void                       onPositioningReply(const SDecorationPositioningReply& reply);
+
+    virtual void                       draw(CMonitor*, float a, const Vector2D& offset);
+
+    virtual eDecorationType            getDecorationType();
+
+    virtual void                       updateWindow(CWindow*);
+
+    virtual void                       damageEntire();
+
+    virtual eDecorationLayer           getDecorationLayer();
+
+    virtual uint64_t                   getDecorationFlags();
+
+  private:
+    SWindowDecorationExtents m_seExtents;
+    SWindowDecorationExtents m_seReportedExtents;
+
+    CWindow*                 m_pWindow = nullptr;
+
+    Vector2D                 m_vLastWindowPos;
+    Vector2D                 m_vLastWindowSize;
+
+    CBox                     m_bAssignedGeometry = {0};
+
+    CBox                     assignedBoxGlobal();
+    bool                     doesntWantBorders();
+};