aruco: correctly round pixels when computing marker size & fix assertion

modules/aruco/src/aruco.cpp

@@ -1505,7 +1505,7 @@ void _drawPlanarBoardImpl(Board *_board, Size outSize, OutputArray _img, int mar
             pf -= Point2f(minX, minY);
             pf.x = pf.x / sizeX * float(out.cols);
             pf.y = (1.0f - pf.y / sizeY) * float(out.rows);
-            outCorners[j] = Point(pf);
+            outCorners[j] = pf;
         }
 
         // get marker

modules/aruco/src/dictionary.cpp

@@ -163,7 +163,7 @@ int Dictionary::getDistanceToId(InputArray bits, int id, bool allRotations) cons
  */
 void Dictionary::drawMarker(int id, int sidePixels, OutputArray _img, int borderBits) const {
 
-    CV_Assert(sidePixels > markerSize);
+    CV_Assert(sidePixels >= (markerSize + 2*borderBits));
     CV_Assert(id < bytesList.rows);
     CV_Assert(borderBits > 0);