file_toScreenRect.html

Enable keyboard shortcuts

<!DOCTYPE HTML>

<meta charset="utf-8">

<meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1">

<link rel="stylesheet" href="/tests/SimpleTest/test.css" />

<style>

html,body {

  margin: 0;

  padding: 0;

#target {

  position: absolute;

  top: 150px;

  left: 150px;

  width: 100px;

  height: 100px;

  background-color: blue;

</style>

<div id="target"></div>

<script>

const isfuzzy = opener.isfuzzy.bind(opener);

const add_task = opener.add_task.bind(opener);

const original_finish = opener.SimpleTest.finish;

const SimpleTest = opener.SimpleTest;

SimpleTest.finish = function finish() {

  self.close();

  original_finish();

};

add_task(async () => {

  await SpecialPowers.pushPrefEnv({'set': [['layout.css.devPixelsPerPx', 1.5]]});

  SpecialPowers.setFullZoom(window, 2.0);

  const rect = target.getBoundingClientRect();

  const screenPixelsPerCSSPixel = window.devicePixelRatio;

  let rectOnScreen =

    SpecialPowers.DOMWindowUtils.toScreenRect(rect.x, rect.y, rect.width, rect.height);

  isfuzzy(rectOnScreen.x,

     rect.x * screenPixelsPerCSSPixel +

     window.mozInnerScreenX * screenPixelsPerCSSPixel, 0.01, "x");

  isfuzzy(rectOnScreen.y,

     rect.y * screenPixelsPerCSSPixel +

     window.mozInnerScreenY * screenPixelsPerCSSPixel, 0.01, "y");

  isfuzzy(rectOnScreen.width, rect.width * screenPixelsPerCSSPixel, 0.01, "width");

  isfuzzy(rectOnScreen.height, rect.height * screenPixelsPerCSSPixel, 0.01, "height");

});

</script>