diff --git a/src/drawing.c b/src/drawing.c
index f6a4c27..b1d92b5 100644
--- a/src/drawing.c
+++ b/src/drawing.c
@@ -675,8 +675,10 @@ static void strokeAddCorner(
 		if (cl >  3) cl =  3;
 		strokeAddPoint(stroke, x0, y0, nx*cl, ny*cl);
 	} else {
-		// flat
+		// half circle
 		strokeAddPoint(stroke, x0, y0, ny0, -nx0);
+		strokeAddCornerSub(stroke, nx0, ny0, precisionSqr, 8);
+		strokeAddCornerSub(stroke, ny1, -nx1, precisionSqr, 8);
 	}
 }
 
@@ -687,7 +689,7 @@ static void strokeDraw(HeliStroke *stroke, double w, double *color, int antialia
 		double c1[4] = { color[0], color[1], color[2], color[3] };
 		double w0 = w + 0.5*aaBorder;
 		double w1 = w - 0.5*aaBorder;
-		if (w1 < HELI_PRECISION) {
+		if (!(w1 > HELI_PRECISION)) {
 			c1[3] *= w0/aaBorder;
 			w1 = 0;
 		}
@@ -732,8 +734,8 @@ static void strokeDraw(HeliStroke *stroke, double w, double *color, int antialia
 
 static void drawStroke(int close) {
 	HeliDrawingState *s = heliDrawingGetState();
-	if (s->strokeColor[3] <= HELI_PRECISION) return;
-	if (s->strokeWidth < HELI_PRECISION) return;
+	if (!(s->strokeColor[3] > HELI_PRECISION)) return;
+	if (!(s->strokeWidth > HELI_PRECISION)) return;
 	if (pathSize < 4) return;
 	
 	HeliStroke stroke = {};