diff --git a/libs/graphic/graphic.cpp b/libs/graphic/graphic.cpp
index ffad2b2..8ee8b3d 100644
--- a/libs/graphic/graphic.cpp
+++ b/libs/graphic/graphic.cpp
@@ -2206,43 +2206,47 @@ void Graphic::calcLOD(int index) {
 	if (!m_LODOptimization) return;
 	GraphicType & t(graphics[index]);
 	t._lod.clear();
+	t._lod.reserve(32);
 	int pcnt = t.polyline.size();
 	// qDebug() << "calcLOD" << index;
 	while (pcnt >= 10) {
 		QPolygonF & pl(t._lod.isEmpty() ? t.polyline : t._lod.back());
 		t._lod.append(QPolygonF());
 		QPolygonF & cl(t._lod.back());
-		cl << pl.front();
-		int qcnt    = (pl.size() + 1) / 4;
-		pcnt        = qcnt * 2 + 2;
-		int pc      = 4;
-		qreal mx[2] = {0., 0.}, my[2] = {0., 0.}, my_x[2] = {0., 0.}, px, py;
-		for (int i = 0; i < qcnt; ++i) {
-			int j = i * 4 + 1;
-			if (i == qcnt - 1) pc = pl.size() - j - 1;
-			mx[0] = mx[1] = my_x[0] = my_x[1] = pl[j].x();
-			my[0] = my[1] = pl[j].y();
-			for (int k = 1; k < pc; ++k) {
-				px    = pl[j + k].x();
-				py    = pl[j + k].y();
-				mx[0] = qMin(mx[0], px);
-				mx[1] = qMax(mx[1], px);
-				if (my[0] > py) {
-					my[0]   = py;
-					my_x[0] = px;
-				}
-				if (my[1] < py) {
-					my[1]   = py;
-					my_x[1] = px;
+		if (pl.size() > 4) {
+			cl << pl.front();
+			int qcnt    = (pl.size() + 1) / 4;
+			pcnt        = qcnt * 2 + 2;
+			int pc      = 4;
+			qreal mx[2] = {0., 0.}, my[2] = {0., 0.}, my_x[2] = {0., 0.}, px, py;
+			for (int i = 0; i < qcnt; ++i) {
+				int j = i * 4 + 1;
+				if (i == qcnt - 1) pc = pl.size() - j - 1;
+				mx[0] = mx[1] = my_x[0] = my_x[1] = pl[j].x();
+				my[0] = my[1] = pl[j].y();
+				for (int k = 1; k < pc; ++k) {
+					px    = pl[j + k].x();
+					py    = pl[j + k].y();
+					mx[0] = qMin(mx[0], px);
+					mx[1] = qMax(mx[1], px);
+					if (my[0] > py) {
+						my[0]   = py;
+						my_x[0] = px;
+					}
+					if (my[1] < py) {
+						my[1]   = py;
+						my_x[1] = px;
+					}
 				}
+				qreal dx = (mx[1] - mx[0]) / 4., cx = (mx[1] + mx[0]) / 2.;
+				if (my_x[1] >= my_x[0])
+					cl << QPointF(cx - dx, my[0]) << QPointF(cx + dx, my[1]);
+				else
+					cl << QPointF(cx - dx, my[1]) << QPointF(cx + dx, my[0]);
 			}
-			qreal dx = (mx[1] - mx[0]) / 4., cx = (mx[1] + mx[0]) / 2.;
-			if (my_x[1] >= my_x[0])
-				cl << QPointF(cx - dx, my[0]) << QPointF(cx + dx, my[1]);
-			else
-				cl << QPointF(cx - dx, my[1]) << QPointF(cx + dx, my[0]);
-		}
-		cl << pl.back();
+			cl << pl.back();
+		} else
+			cl = pl;
 		// qDebug() << "lod" << t._lod.size() << "->" << cl.size();
 	}
 }