Function zoomAtPoint

app.js:1198–1222

(clientX, clientY, newZoom)

}

function zoomAtPoint(clientX, clientY, newZoom) {
  const wrapper = document.querySelector(".preview-wrapper");
  if (!wrapper || !previewViewport) {
    setZoom(newZoom);
    return;
  }
  // OLED: zoom is pixel-perfect via updatePreviewSize, so skip cursor-anchored transform math.
  if (driverMode === "u8g2") {
    setZoom(newZoom);
    return;
  }
  const rect = wrapper.getBoundingClientRect();
  const px = clientX - rect.left;
  const py = clientY - rect.top;
  const oldZ = clamp(zoomFactor || 1, 0.5, 3);
  const targetZ = clamp(newZoom, 0.5, 3);
  const wx = (px - viewportPanX) / oldZ;
  const wy = (py - viewportPanY) / oldZ;
  viewportPanX = px - wx * targetZ;
  viewportPanY = py - wy * targetZ;
  zoomFactor = targetZ;
  if (zoomSlider) zoomSlider.value = String(Math.round(zoomFactor * 100));
  if (zoomInput) zoomInput.value = String(Math.round(zoomFactor * 100));
  applyViewportTransform();
}

document.addEventListener("keydown", (e) => {
  const tag = e.target && e.target.tagName ? e.target.tagName.toLowerCase() : "";