diff --git a/src/libslic3r/SLA/Rotfinder.cpp b/src/libslic3r/SLA/Rotfinder.cpp
index f410eb0e1..79be5e1ec 100644
--- a/src/libslic3r/SLA/Rotfinder.cpp
+++ b/src/libslic3r/SLA/Rotfinder.cpp
@@ -92,10 +92,9 @@ Transform3f to_transform3f(const XYRotation &rot)
 
 } // namespace
 
-Vec2d find_best_rotation(const SLAPrintObject &        po,
-                         float                         accuracy,
-                         std::function<void(unsigned)> statuscb,
-                         std::function<bool()>         stopcond)
+Vec2d find_best_rotation(const SLAPrintObject &   po,
+                         float                    accuracy,
+                         std::function<bool(int)> statuscb)
 {
     static const unsigned MAX_TRIES = 1000;
 
@@ -108,7 +107,7 @@ Vec2d find_best_rotation(const SLAPrintObject &        po,
     mesh.require_shared_vertices();
 
     // To keep track of the number of iterations
-    unsigned status = 0;
+    int status = 0;
 
     // The maximum number of iterations
     auto max_tries = unsigned(accuracy * MAX_TRIES);
@@ -118,7 +117,11 @@ Vec2d find_best_rotation(const SLAPrintObject &        po,
 
     auto statusfn = [&statuscb, &status, &max_tries] {
         // report status
-        statuscb(unsigned(++status * 100.0/max_tries) );
+        statuscb(++status * 100.0/max_tries);
+    };
+
+    auto stopcond = [&statuscb] {
+        return ! statuscb(-1);
     };
 
     // Preparing the optimizer.
diff --git a/src/libslic3r/SLA/Rotfinder.hpp b/src/libslic3r/SLA/Rotfinder.hpp
index a6fde2c9d..2b92c52b8 100644
--- a/src/libslic3r/SLA/Rotfinder.hpp
+++ b/src/libslic3r/SLA/Rotfinder.hpp
@@ -19,19 +19,19 @@ namespace sla {
   * @param accuracy The optimization accuracy from 0.0f to 1.0f. Currently,
   * the nlopt genetic optimizer is used and the number of iterations is
   * accuracy * 100000. This can change in the future.
-  * @param statuscb A status indicator callback called with the unsigned
+  * @param statuscb A status indicator callback called with the int
   * argument spanning from 0 to 100. May not reach 100 if the optimization finds
-  * an optimum before max iterations are reached.
-  * @param stopcond A function that if returns true, the search process will be
-  * terminated and the best solution found will be returned.
+  * an optimum before max iterations are reached. It should return a boolean
+  * signaling if the operation may continue (true) or not (false). A status
+  * value lower than 0 shall not update the status but still return a valid
+  * continuation indicator.
   *
   * @return Returns the rotations around each axis (x, y, z)
   */
 Vec2d find_best_rotation(
         const SLAPrintObject& modelobj,
         float accuracy = 1.0f,
-        std::function<void(unsigned)> statuscb = [] (unsigned) {},
-        std::function<bool()> stopcond = [] () { return false; }
+        std::function<bool(int)> statuscb = [] (int) { return true; }
         );
 
 double get_model_supportedness(const SLAPrintObject &mesh,
diff --git a/src/slic3r/GUI/Jobs/RotoptimizeJob.cpp b/src/slic3r/GUI/Jobs/RotoptimizeJob.cpp
index ac737cafb..7e1bfaeeb 100644
--- a/src/slic3r/GUI/Jobs/RotoptimizeJob.cpp
+++ b/src/slic3r/GUI/Jobs/RotoptimizeJob.cpp
@@ -21,13 +21,12 @@ void RotoptimizeJob::process()
 
     if (!o || !po) return;
 
-    Vec2d r = sla::find_best_rotation(*po, 0.75f,
-        [this](unsigned s) {
-            if (s < 100)
-                update_status(int(s), _(L("Searching for optimal orientation")));
-        },
-        [this] () { return was_canceled(); });
+    Vec2d r = sla::find_best_rotation(*po, 0.75f, [this](int s) {
+        if (s > 0 && s < 100)
+            update_status(s, _(L("Searching for optimal orientation")));
 
+        return !was_canceled();
+    });
 
     double mindist = 6.0; // FIXME