diff --git a/index.html b/index.html
index b3a9920..9bd6d43 100644
--- a/index.html
+++ b/index.html
@@ -950,7 +950,8 @@ function lucky(p, kind) {
 /* ---------------- collisions & scoring ---------------- */
 function pipeHit(box) {
   for (const p of S.pipes) {
-    const top = { x: p.x, y: 0, w: p.theme.w, h: p.gapY };
+    /* the upper column reaches up past the top of the screen */
+    const top = { x: p.x, y: -1e5, w: p.theme.w, h: p.gapY + 1e5 };
     const bot = { x: p.x, y: p.gapY + p.gap, w: p.theme.w, h: GROUND_Y - (p.gapY + p.gap) };
     if (aabb(box, top) || aabb(box, bot)) return p;
   }
@@ -1362,9 +1363,12 @@ function drawPipe(p) {
   const topH = p.gapY;
   const botY = p.gapY + p.gap;
   const botH = GROUND_Y - botY;
+  /* the column starts above the top of the screen so the barrier always
+     reaches the top edge, whatever shape the device is */
+  const startY = Math.floor((-VIEW.oy / VIEW.scale) / BLOCK) * BLOCK;
   for (let col = 0; col < cols; col++) {
     const bx = Math.round(p.x + col * BLOCK);
-    for (let y = 0; y < topH; y += BLOCK) {
+    for (let y = startY; y < topH; y += BLOCK) {
       block(ctx, bx, y, (y + BLOCK > topH - BLOCK) ? th.top : th.body, p.seed + col);
     }
     for (let y = botY; y < botY + botH; y += BLOCK) {