Databases
StackOverflow2013
Postsdbo
PO-webkit-transform scale: how to get the coordinates of a visible area
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO-webkit-transform scale: how to get the coordinates of a visible area
    primarykey
    data
    text
    <p>I have an image which is displayed in a fixed div.</p> <pre><code>&lt;div&gt; &lt;img src="path/to/image" id="map" /&gt; &lt;/div&gt; </code></pre> <p>I'm using the -webkit-transform property to scale and navigate to the scaled image (not other browsers required. just webkit). All the stuff is being done with javascript/jquery. The navigation works in any directions. The maximum scale zoom is 10.</p> <p>E.g.:</p> <pre><code>&lt;button id="up"&gt;zoom in and move up&lt;/button&gt; $('#up').on('click',function() { $('#map').css({'webkitTransform':'translateX('+SOME_VALUE+'px) translateY('+SOME_VALUE+'px) scale('+ SCALE +')'}); }); </code></pre> <p>Everything works fine.</p> <p>The difficulty is in a different place: </p> <p>The image has a circle point on it. I know the coordinates of this point and its radius (e.g. X-100px,Y-100px,R-10px); These coordinates are related to the image.</p> <h2>Question:</h2> <p>How can I determine whether this circle point is visible or not if the image is scaled? How can I determine what area of the image is visible? How can I determine its <em>actual</em> coordinates in the resized state. Please do not hesitate to take a look at the example image that shows the desired:</p> <p><img src="https://i.stack.imgur.com/ukZgW.jpg" alt="Image"></p> <p>UPDATE:</p> <p>Unfortunately, the solutions given below are not quite correct. By multiplying jquery value of the height() and the scale rate you won't get the accurate results. I found the solution myself. There is the following javascript (not jquery) property:</p> <p><a href="https://developer.mozilla.org/en-US/docs/Web/API/element.getBoundingClientRect?redirectlocale=en-US&amp;redirectslug=DOM/element.getBoundingClientRect" rel="nofollow noreferrer">element.getBoundingClientRect</a></p> <p>This property reflects the real dimensions of the resized image and returns the real coordinates of an actual position. The usage with jquery is the following:</p> <pre><code>$('#some_element')[0].getBoundingClientRect(); </code></pre> <p>I hope it will be useful for those guys who meet the problem in the future:)</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USSsey
    1. USSsey
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. PO-webkit-transform scale: how to get the coordinates of a visible area
      1. This table or related slice is empty.
      1. VTUpMod
    1. COIf it answers your question, you should post it as an answer and link to where you found the solution (blog, documentation, etc).
      singulars
      1. PO-webkit-transform scale: how to get the coordinates of a visible area
      1. USalex
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload