From 2b0abbe05a15767d4952f2a36b3e9df3bde15c3e Mon Sep 17 00:00:00 2001
From: nds <natalia.donis@opencascade.com>
Date: Mon, 29 Dec 2014 13:06:50 +0300
Subject: [PATCH] An arc moving correction for dragging it by the center point.

---
 src/SketchPlugin/SketchPlugin_Arc.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/SketchPlugin/SketchPlugin_Arc.cpp b/src/SketchPlugin/SketchPlugin_Arc.cpp
index d6a6facfa..3acdb0e31 100644
--- a/src/SketchPlugin/SketchPlugin_Arc.cpp
+++ b/src/SketchPlugin/SketchPlugin_Arc.cpp
@@ -237,5 +237,14 @@ void SketchPlugin_Arc::attributeChanged(const std::string& theID)
     if (aProjection && aStartAttr->pnt()->distance(aProjection) > tolerance)
       aStartAttr->setValue(aProjection);
     myStartUpdate = false;
+  } else if (theID == CENTER_ID() && !myEndUpdate) {
+    myEndUpdate = true;
+    // compute and change the arc end point
+    std::shared_ptr<GeomAPI_Circ2d> aCircleForArc(
+        new GeomAPI_Circ2d(aCenterAttr->pnt(), aStartAttr->pnt()));
+    std::shared_ptr<GeomAPI_Pnt2d> aProjection = aCircleForArc->project(anEndAttr->pnt());
+    if (aProjection && anEndAttr->pnt()->distance(aProjection) > tolerance)
+      anEndAttr->setValue(aProjection);
+    myEndUpdate = false;
   }
 }
-- 
2.39.2