First opengl/x11/window integration.

src/mesh/TriFace.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <memory>
+#include <vector>
 
 class Edge;
 
@@ -11,6 +12,8 @@ public:
     ~TriFace();
 
     static std::unique_ptr<TriFace> Create(Edge* edge0, Edge* edge1, Edge* edge2, unsigned id=0);
+
+    std::vector<unsigned> getNodeIds() const;
 private:
     unsigned mId{0};
     Edge* mEdge0{nullptr};