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Detect initial device orientation values

I'm trying to manually create a parallax effect of sorts, and so far here's my JavaScript:
var bottom = document.getElementById("bottom");
var top = document.getElementById("top");
window.addEventListener("deviceorientation", function(e) {
var gamma = e.gamma;
var beta = e.beta;
$(bottom).css('left',(gamma/2)+'px').css('top',(beta/2)+'px');
$(top).css('left',(gamma)+'px').css('top',(beta)+'px');
});
So far its working great and I have the effect I want, but the starting position of the device is not quite what I want. Currently the alpha, beta, and gamma values are only at 0,0,0 if the device is flat on the table. What I want to do is that when you load the page, that position is taken as 0,0,0.
For example, if I am reading my phone in my hand, then of course my phone is going to be at an angle already, and I want to take this starting position as 0,0,0 when the page is loaded.
So to put that into some sort of pseudo code, here's what I'm trying to achieve:
gammaOnLoad and betaOnLoad = initial device orientation
gammaCurrent and betaCurrent = e.gamma and e.beta (from event listener)
gammaDifference and betaDifference = Math.abs(gammaOnLoad - gammaCurrent)
$(elem).css('left', gammaDifference + 'px').css('top', betaDifference + 'px');
So essentially you take in the values when loading the page and use those as 0, your point of origin. This means that whatever angle your phone is at, when you load the page the image will always look normal and from there it will begin the parallax effect.

I wanted to do the same thing as you. This is very basic, but it seems to work:
$(document).ready(function() {
var origLR, origFB;
function setOrigin(eventData) {
origLR = eventData.gamma;
origFB = eventData.beta;
}
if (window.DeviceOrientationEvent) {
window.addEventListener('deviceorientation', setOrigin, false);
setTimeout(function() {
window.removeEventListener('deviceorientation', setOrigin, false);
window.addEventListener('deviceorientation', function(eventData) {
var tiltLR = eventData.gamma,
tiltFB = eventData.beta;
tiltLR = (origLR - tiltLR);
tiltFB = (origFB - tiltFB);
deviceOrientationHandler(tiltLR, tiltFB);
}, false);
}, 100);
};
function deviceOrientationHandler(tiltLR, tiltFB) {
$('.bottom').css('transform','translateX(' + (tiltLR/5) + 'px) translateY(' + (tiltFB/5) + 'px)');
$('.top').css('transform','translateX(' + (tiltLR/2.5) + 'px) translateY(' + (tiltFB/2.5) + 'px)');
}
});
I added an event listener for 100ms that sets the initial device orientation values, then removed it and replaced it with one that calculates the difference between initial and current.
This can probably be more efficient, I'm not a particularly experienced programmer.

jQuery Variable Height

I'm trying to have an image gallery where a caption is vertically centered inside of a slideshow, here's the code I'm working with
$(window).load(function() {
var imageHeight = $('.flexslider .slides li img').height();
var captionTop = imageHeight - $('.title-cap').height();
var captionTop = captionTop/2;
$('.title-cap').css('top',captionTop + 'px');
var captionTopOne = imageHeight - $('.sub-cap-one').height();
var captionTopOne = captionTopOne/2;
$('.sub-cap-one').css('top',captionTopOne + 'px');
var captionTopTwo = imageHeight - $('.sub-cap-two').height();
var captionTopTwo = captionTopTwo/2;
$('.sub-cap-two').css('top',captionTopTwo + 'px');
var captionTopThr = imageHeight - $('.sub-cap-three').height();
var captionTopThr = captionTopThr/2;
$('.sub-cap-three').css('top',captionTopThr + 'px');
});
The caption is positioned absolutely, and I'm using top to do the centering...
So my thought process is, get the height of the base slideshow image to keep it responsive, minus the height of the current caption, and divide that by two ending with the top value.
The first instance is working, with "title-cap", but the next three are not. They all return the same wrong value. All caption classes have the same attributes, just different for assignment.
Also, what would I need to add in order for the values to dynamically change with the browser window size in real time.
Edit: Alright, did a little research and figured out the load/resize part.
This is what I have now
function setContent(){
[Added all of the above minus the onload part in here]
}
$(window).load(function() {
setContent();
});
$(window).resize(function() {
setContent();
});
Now just not sure why the sub-cap's aren't loading properly. Any ideas?

I've had similar problem when trying to get the size of hidden elements. I found this nice jQuery actual plugin. It might be what you need.

Javascript dialog is programmed to move when the page scrolls, but it flickers. Can this be fixed?

I've written some jQuery code to display a box with data in the corner of the users' web browser. I'm using the .scroll event to make the box stay in the corner as the user scrolls up and down the page. Let me emphasize that I am not using jquery-ui dialog.
The only problem is that the box flickers as the page scrolls. I'm afraid that there will be no cross-browser solution to this problem as the different browsers seem to behave differently with scrolling. Barring a cross-browser solution, an IE solution would be nice (My web application is designed to be used by a specific group of about 100 users in my organization.)
Here are snippets of the relative code:
ExternalScroll: function () {
LittleBlackBook.setPosition();
}
setPosition: function () {
var scrollPosition = $(self).scrollTop();
var cssTop = LittleBlackBookStatic.determineCssTop(this.height, this.isTop, this.vOffset, scrollPosition);
var cssHeight = LittleBlackBookStatic.determineCssHeight(this.height);
var cssLeft = LittleBlackBookStatic.determineCssLeft(this.width, this.isLeft, this.hOffset);
var cssWidth = LittleBlackBookStatic.determineCssWidth(this.width);
this.jQueryObj.css('top', cssTop);
this.jQueryObj.css('height', cssHeight);
this.jQueryObj.css('left', cssLeft);
this.jQueryObj.css('width', cssWidth);
}
var LittleBlackBookStatic = {
determineCssTop: function (height, isTop, vOffset, vScroll) {
var windowHeight = $(self).height();
var scrollPosition = $(self).scrollTop();
var newModalTop = isTop ? vOffset + vScroll : windowHeight - height + vScroll - vOffset;
return newModalTop + 'px';
},
determineCssHeight: function (height) {
return height + 'px';
},
determineCssLeft: function (width, isLeft, hOffset) {
var windowWidth = $(self).width();
var newModalLeft = isLeft ? hOffset : windowWidth - width - hOffset;
return newModalLeft + 'px';
},
determineCssWidth: function (width) {
return width + 'px';
}
} // end LittleBlackBookStatic
I'm using jQuery to look up the scroll position as the page scrolls and change the CSS.
Is there a better way; a way that will make it scroll without flickering? If no, then why not?

You should use fixed positioning for that box instead instead of animating it to keep it in the corner.
You'll use less javascript and avoid flickering that comes with animation.

How do i make "facebook zoom"

Im making a website, and i love the functionality of this google chrome extension call Facebook Photo Zoom # https://chrome.google.com/extensions/detail/elioihkkcdgakfbahdoddophfngopipi
I think the essential idea behind the extension is when you hover over the thumbnail, it grabs the original image file and displays it in full view. If the image is too big, then it will be position on the corners or the top and bottom bars of the window. If it is not too big, it will float next to the mouse position.
The logic behind it i understand, but the actually coding seems to be a bit daunting. I guess the only parts of it i dont understand is how do you code the positions of the expanded images and make them contract/expand when you move your mouse to the left/right. Thanks

13 zoom jquery plugins in here. Choose the best for your needs:)

on mouseover you create big image with
css({position: 'absolute', left: e.pageX, top: e.pageY})
on mousemove you update the left and top in the same way.
check also:
http://api.jquery.com/event.pageY/
http://api.jquery.com/css/
http://api.jquery.com/event.pageX/

Check out this preview image tooltip which is similar to what that Chrome extension does, but you have to provide it the url to the thumbnail and full sized image. Here is the original blog post.
I modified the script to adjust the image size to fit the distance between the cursor and right browser edge. It's not perfect, but it works. Here is a demo.
/*
* Image preview script
* powered by jQuery (http://www.jquery.com)
*
* written by Alen Grakalic (http://cssglobe.com)
*
* for more info visit http://cssglobe.com/post/1695/easiest-tooltip-and-image-preview-using-jquery
*
*/
this.imagePreview = function(){
/* CONFIG */
xOffset = 10;
yOffset = 20;
// these 2 variable determine popup's distance from the cursor
// you might want to adjust to get the right result
/* END CONFIG */
$('a.preview').hover(function(e){
this.t = this.title;
this.title = '';
var p, c = (this.t != '') ? '<br/>' + this.t : '';
$('body').append('<p id="preview"><img src="' + this.href + '" alt="Image preview" />' + c + '</p>');
// load image and get size
p = $('#preview');
p
.fadeIn('fast')
.find('img').load(function(){
// get image dimensions after it has been loaded
p.data('widths', [ $(window).width(), p.find('img').width() ]);
// set image to 100% to fit in preview window
$(this).width('100%');
position(e);
});
},
function(){
this.title = this.t;
$('#preview').remove();
});
$('a.preview').mousemove(function(e){
position(e);
});
var position = function(e){
var w, prevw = $('#preview'),
w = $.data( prevw[0], 'widths' );
if ( w ) {
prevw
.css('top', e.pageY + yOffset)
.css('left', e.pageX + xOffset)
.css('max-width', (e.pageX + prevw.outerWidth() > w[0]) ? w[0] - e.pageX - xOffset : w[1] || 'auto' );
}
};
};
// starting the script on page load
$(document).ready(function(){
imagePreview();
});

See the Kabbar Image Zoomer at http://www.ideabonus.com/Kabbar/index.html

How do I get slimbox 2 to auto-resize to fit the screen?

According to the Slimbox2 documentation this function isn't supported. But I was wondering if anyone had encountered any tricks to make this work.
The main concern I have is that some of my images are fairly lengthy, and at low resolution LightBox2 would create an annoying experience for the user.

I recently started to use slimbox2 on my website (http://www.trips.elusien.co.uk) and found that it could benefit from a few modifications:
"slide resize": this makes the size of the slideshow constant, rather than depending on the size of the image (by specifying a pixel size), or you can use a percentage to make the slides larger or smaller in the slideshow. You specify this using 2 new options:
slideWidth: 0, // Initial width of the slide (in pixels or in percent as a string e.g. "50%")
slideHeight: 0, // Initial height of the slide (in pixels or in percent as a string e.g. "50%")
enable the slides to be flipped automatically, rather than manually. You specify this using a new option:
slideInterval: 0, // Interval between flipping slides (in seconds), 0 means no automation.
download the slides from the slideshow.
The first and last features cannot be done with the origal version of slimbox2 since in that version the image is displayed as a BACKGROUND image, rather than using the "IMG" tag.
I have put the Javascript and CSS files on my website. If you want to try them go to my website and click on the "slimbox examples" link, you can download them from here. To see a neat way of using slimbox2 click in the "photoSLide Show" link on the home-page.
Regards Neil

its easy to fix check my code.
find and replace the three lines in slimbox2.js file:
$(image).css({backgroundImage: "url(" + activeURL + ")", visibility: "hidden", display: ""});
$(sizer).width(preload.width);
$([sizer, prevLink, nextLink]).height(preload.height);
with:
/* make sure the image won't be bigger than the window */
window.innerWidth = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth; //ie fix
window.innerHeight = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight; //ie fix
var winWidth = window.innerWidth-200; //browser width
var winHeight = window.innerHeight-100; //browser height
var my_w = preload.width; //original width
var my_h = preload.height; //original height
// scale width
var scaleW1 = winWidth;
var scaleH1 = (my_h * winWidth) / my_w;
// scale height
var scaleW2 = (my_w * winHeight) / my_h;
var scaleH2 = winHeight;
var scale = (scaleW2 > winWidth);
if (scale) {
reswidth = Math.floor(scaleW1);
resheight = Math.floor(scaleH1);
}
else {
reswidth = Math.floor(scaleW2);
resheight = Math.floor(scaleH2);
}
if ($("p").hasClass("slimboxie")){
$(image).css({filter:"progid:DXImageTransform.Microsoft.AlphaImageLoader( src='"+ activeURL + "', sizingMethod='scale')", visibility: "hidden", display: ""});
$(sizer).width(reswidth);
$([sizer, prevLink, nextLink]).height(resheight); }
else {
$(image).css({backgroundImage: "url(" + activeURL + ")", backgroundSize: reswidth + "px " + resheight + "px", visibility: "hidden", display: ""});
$(sizer).width(reswidth);
$([sizer, prevLink, nextLink]).height(resheight);
}
im amateur at javascript but i think its working great. I made it work with IE8 also. You only need to insert:
<!--[if IE 8]>
<p class="slimboxie"></p>
<![endif]-->

after loading the image, do this:
$('#lbImage').css('background-size', 'contain');