From da569352cc264e1ef70b8e7e223a73a1b49cb91e Mon Sep 17 00:00:00 2001
From: "jakob.schratter" <jakob.schratter@edu.uni-graz.at>
Date: Tue, 27 Jan 2026 16:37:38 +0100
Subject: [PATCH] wet coords

---
 mgrid_2/geom.cpp        | 16 ++++++++++++++++
 mgrid_2/geom.h          |  2 +-
 solid-cpp/ownSolver.cpp | 18 ++++++++++++------
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/mgrid_2/geom.cpp b/mgrid_2/geom.cpp
index 7ed1ef0..3b3f1d9 100644
--- a/mgrid_2/geom.cpp
+++ b/mgrid_2/geom.cpp
@@ -847,6 +847,22 @@ const std::vector<int> Mesh::EdgeSubdomains() const
     return _edgeSubdomains;
 }
 
+const std::vector<int> Mesh::TopNodes() const
+{
+    vector<int> topNodes;
+
+    for (size_t i = 0; i < _outerEdgesNodes.size(); ++i)
+    {
+        int nodeIndex = _outerEdgesNodes[i];
+        if (abs(_xc[2*nodeIndex + 1] - 105.0) < 0.01 )      // if y-coordinate of node is 105, i.e. node is on top
+        {
+            topNodes.push_back(nodeIndex);
+        }
+    }
+
+    return topNodes;
+}
+
 
 // Only the outer edges for Robin BC
 void Mesh::InitializeOuterEdges()
diff --git a/mgrid_2/geom.h b/mgrid_2/geom.h
index 70698b3..d5d0108 100644
--- a/mgrid_2/geom.h
+++ b/mgrid_2/geom.h
@@ -352,7 +352,7 @@ public:
     const std::vector<int> OuterEdgesNodes() const;
     const std::vector<int> ElementSubdomains() const;
     const std::vector<int> EdgeSubdomains() const;
-
+    const std::vector<int> TopNodes() const;
 
 
 
diff --git a/solid-cpp/ownSolver.cpp b/solid-cpp/ownSolver.cpp
index 36d0ba9..2741caf 100644
--- a/solid-cpp/ownSolver.cpp
+++ b/solid-cpp/ownSolver.cpp
@@ -106,14 +106,20 @@ int main(int argc, char **argv )
     precice::Participant participantSolid(solverName, configFileName, commRank, commSize);
 
     int meshDim  = participantSolid.getMeshDimensions(meshName); // gets mesh dimensions (=2) from config file
-    int numberOfVertices; // number of vertices at "wet" surface
+
+    // Determine number of "wet" vertices
+    vector<int> wetNodes = mesh_c.TopNodes();
+    int numberOfVertices = wetNodes.size();
+
+    // Determine coordinates of "wet" vertices
+    std::vector<double> allCoords = mesh_c.GetCoords();
+    std::vector<double> coords(numberOfVertices*meshDim);
+    for (size_t i = 0; i < numberOfVertices*meshDim; ++i)
     {
-        // TODO: DETERMINE NUMBER OF VERTICES AT TOP
-    }
-    std::vector<double> coords(numberOfVertices*meshDim); // coords of vertices at "wet" surface
-    {
-        // TODO: DETERMINE COORDINATES OF VERTICES AT TOP
+        coords.push_back(allCoords[2*wetNodes[i]]);     // x-coord of node
+        coords.push_back(allCoords[2*wetNodes[i + 1]]); // y-coord of node
     }
+
     std::vector<int> vertexIDs(numberOfVertices);
     
     participantSolid.setMeshVertices(meshName, coords, vertexIDs);