#5746: Implement face vertex manipulation for two selected vertices

radiantcore/selection/textool/FaceNode.h

@@ -74,7 +74,7 @@ class FaceNode :
         auto selectionCount = selectedIndices.size();
 
         Vector3 vertices[3];
-        Vector2 texcoords[2];
+        Vector2 texcoords[3];
         const auto& winding = _face.getWinding();
 
         if (selectionCount >= 3)
@@ -87,6 +87,23 @@ class FaceNode :
                 texcoords[i] = _vertices[selectedIndices[i]].getTexcoord();
             }
 
+            _face.setTexDefFromPoints(vertices, texcoords);
+        }
+        else if (selectionCount == 2)
+        {
+            // Calculate the center point of the selection and pick the vertex that is farthest from it
+            auto selectionBounds = getSelectedComponentBounds();
+            auto farthestIndex = findIndexFarthestFrom({ selectionBounds.origin.x(), selectionBounds.origin.y() });
+
+            for (std::size_t i = 0; i < 2; ++i)
+            {
+                vertices[i] = _vertices[selectedIndices[i]].getVertex();
+                texcoords[i] = _vertices[selectedIndices[i]].getTexcoord();
+            }
+
+            vertices[2] = _vertices[farthestIndex].getVertex();
+            texcoords[2] = _vertices[farthestIndex].getTexcoord();
+
             _face.setTexDefFromPoints(vertices, texcoords);
         }
     }
@@ -164,6 +181,31 @@ class FaceNode :
             renderComponents();
         }
     }
+
+private:
+    // Locates the index of the unselected vertex that is farthest away from the given texcoord
+    std::size_t findIndexFarthestFrom(const Vector2& texcoord)
+    {
+        assert(!_vertices.empty());
+
+        std::size_t farthestIndex = 0;
+        double largestDistanceSquared = 0;
+
+        for (std::size_t i = 0; i < _vertices.size(); ++i)
+        {
+            if (_vertices[i].isSelected()) continue;
+
+            auto candidateDistanceSquared = (_vertices[i].getTexcoord() - texcoord).getLengthSquared();
+
+            if (candidateDistanceSquared > largestDistanceSquared)
+            {
+                farthestIndex = i;
+                largestDistanceSquared = candidateDistanceSquared;
+            }
+        }
+
+        return farthestIndex;
+    }
 };
 
 }

test/TextureTool.cpp

@@ -1036,24 +1036,27 @@ TEST_F(TextureToolTest, DragManipulateSingleFaceVertex)
 // Dragging two selected vertices chooses the one vertex as anchor point which is farthest away from the clicked vertex
 TEST_F(TextureToolTest, DragManipulateTwoFaceVertices)
 {
-    // Vertices 0 and 2 are opposite of each other, but 0 takes the lead
+    // Vertices 0 and 2 are opposite of each other
     std::size_t firstVertex = 0;
     std::size_t secondVertex = 2;
     performFaceVertexManipulationTest(false, { firstVertex, secondVertex }, [&](IFace& face,
         const std::vector<Vector2>& oldTexcoords, const std::vector<Vector2>& changedTexcoords)
     {
-        // Find out which face vertex was the farthest away from the first one
-        int farthestIndex = 1;
-        double largestDistance = 0;
-        for (int i = 0; i < oldTexcoords.size(); ++i)
+        auto center = (changedTexcoords[firstVertex] + changedTexcoords[secondVertex]) * 0.5;
+        // Find out which face vertex was the farthest away from the bounds center of the selection
+        std::size_t farthestIndex = 0;
+        double largestDistanceSquared = 0;
+
+        for (std::size_t i = 0; i < changedTexcoords.size(); ++i)
         {
             if (i == firstVertex || i == secondVertex) continue;
 
-            auto candidateDistance = (oldTexcoords[i] - oldTexcoords[firstVertex]).getLengthSquared();
-            if (candidateDistance > largestDistance)
+            auto candidateDistanceSquared = (changedTexcoords[i] - center).getLengthSquared();
+
+            if (candidateDistanceSquared > largestDistanceSquared)
             {
                 farthestIndex = i;
-                largestDistance = candidateDistance;
+                largestDistanceSquared = candidateDistanceSquared;
             }
         }