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How can i draw a part of an image on top of a html page depending on my mouse movement? (with or without canvas)

I want to draw an image on top of my html page depending on my mouse movement.
How can i do that? Is it a better approach to put the image below the rest of the html and scratch the html somehow away, or tu put the image above it and add it partially on top.
I found solutions on the internet with 2 images on top of each other where the top one is erased with canvas, but since i have multiple elements i want to overwrite, i have no idea how to solve it.

Assuming I've interpreted the question correctly, that the requirement is to allow the user to 'scratch away' at the page gradually revealing an image, you could do it either way.
There are libraries that will create a canvas of a page (or part thereof) such as htm2canvas. Using one of these you turn your page into an image, place it over the given image and remove (make transparent) pixels on the top canvas as the mouse moves. The drawback with this approach is that it's possible the conversion of the HTML to canvas isn't totally complete. There may be some aspects for example of CSS that aren't correctly rendered.
To be sure therefore it's probably better to do it the other way round. Lay a blank canvas over the page and copy the image to another canvas with the same dimensions but which is outside the viewport. As the mouse moves over the blank canvas copy the relevant pixels from the offscreen canvas to it.
If you could confirm that I've understood your question correctly I could go into more detail.

Chrome reloading embedded SVG object when hiding and showing parent DIV container

I am using Adobe Edge Animate to do some CSS3 animations, and using a plugin that converts the SVG images to tags so that the SVG elements are accessible via Javascript. The problem is, when one of the parent DIV containers is hidden and later re-shown, the embedded SVG image is reloaded losing any changes that have been made to it, such as fill colors of shapes, etc.
This also causes some stuttering in the animation when a new image is loaded, as it takes a small amount of time to reload the image.
This problem is not present in Firefox or IE. Is there any way to tell chrome to not re-load embedded images when hidden and shown?
Here is a link to the page in question: Link
If you press the enter key, it triggers part of the animation. You can see after the rotation where it switches out the image and flashes. If you use the built in function via browser console called changeBladeColor() you can see how it resets any changed attributes. This function changes the fill colors of the shapes in the SVG.
Here is an example usage for testing:
changeBladeColor(1, '#ff0000');

It seems the only solution is to position the elements off the page. I had to re-do a lot of my animation, so keep this in mind when doing any projects where you need to display and hide objects (especially ones that may not appear to be doing so).

HTML: Image map areas' responsiveness

I need to use image map in my website, to add different links to each part of image.
But I have problems with its responsiveness. I couldn't change map area's size while resizing window.
Can anyone help me with this? The method is not important, I can use either Js or Css.
Update:
I used http://mattstow.com/experiment/responsive-image-maps/rwd-image-maps.html for responsiveness, but it affects on map area coords. When I reload the page, map coords are all 0, those are being updated only after resizing the window.
Do anyone have this problem too?

Imagemap is a very Old way to create websites I preffer using photoshop image sílice and save as html maybe you should try it ir you will use non dynamic images that way you can fix width and height and a lot more

If you have the image saved as a vector image, you could save it as an SVG and use RaphaelJS. I've only recently picked it up but it is quite easy to use once you get the hang of it.
You can assign links, style and hover events to each node attribute, and Raphael allows you to set the viewBox so that it scales on resize (can't link as rank not high enough - help can easily be found on SO though)
Here are some examples of using RaphaelJS: LINK1 LINK2
And check out jsfiddle.net/AUNwC/294/ for example of each node having a responsive clickable area (resize window to check)

Animated pop-up like on wunderlist.com

I've came across wunderlist.com site and just fell in love with the zoom-like pop-up they have on the image just beneath the header "Learn more about Wunderlist".
I'd love to implement something like this on my site.
Can somebody tell me how this is done? I tried to reverse-engineer, but with no luck :)
I'm not hoping for the whole ready code, but maybe some guidelines on how to achieve this with CSS/jQuery.
Or maybe you know some jQuery plugin that I could use?

They are using all CSS. Pretty simple really.. I would code a full js fiddle example for you but I don't have the time, so instead I will list out the different elements you need and how they interact.
First the large image is just a div with a background image with set
dimensions.
The circular images themselves are generated from one large image containing all of the circles in one spot, this is called a sprite. The circles are just div's with background images and background positioning to position the correct circle inside the box from the sprite image.
The text boxes themselves are also div's with a standard H2 and P tags for the text.
Everything is absolute positioned in order to achieve the proper layout.
The small circles are div's with :hover states that are absolute positioned over their respective targeted areas.
The animation on :hover is achieved by the use of css3 transition and css3 transforms.
This should get you started.
Comment if you have questions.
Had some time to have some fun: http://khill.mhostiuckproductions.com/siteLSSBoilerPlate/fun-experiment-mh/

Try looking at two main aspects:
Open up your inspector tool of choice and look at what happens to body.login .feature
...more specifically, look at what happens to its transform: scale and opacity values upon :hover.
Hint: the transition is mainly on them.
Still in your inspector, change the scale to (1) and the opacity to 1. How it smoothly gets from one state to the other is dictated by the transition property.
This isn't meant to tell you exactly how to achieve it, but to get you on your way :)

It's not that hard actually. The Wunderlist team has even made it easier. They have a large sprite image with the zoomed images cropped and ready with rounded corners, borders and shadows. You can see it here: https://wunderlist2.s3.amazonaws.com/179510ff7c929bfcc6e9819f3c2539baca5d3325/images/welcome-screen.png
What you do is on mouseover you show a half transparent black background (can be position: fixed with full width and height). Then you create a element with the sprite as the background image (even better, have a class ready in your css and append it to your newly created element). Set position to the position of the hovered element.
When added to the dom animate the transform scale of the element (starting with something like scale(.24) as they do).

Well since you tried reverse engineering. I'll try and guide you along that path.
There is only one div with id overlay which is changes it's place & content, on hover of any div with class feature. Work your way further from their app js, it's not minified.
The content of the popup in this case is an image moved to different positions.

Performance Issue on an HTML5 Website

I am building an Webpage that uses SVG, Canvas and, of course, HTML. The idea of this page is to animate the redrawing of some of svg-paths on the canvas. The paths I like to redraw are annotated with an namespace Attribute, all other paths are just displayed as they are. That is all working fine! The performance leak appeared the last two hours while I was adding some content to the page.
But at first a little illustration of the page setup:
The SVG and the Canvas are both 4000 * 4000 px wide and lie directly over each other in one container div. Going from one "page" to another means to tween the upper left edge of this container. This was also working fine since the discussion of inserting text turned in the direction of using html div container, instead of the svg itself.
So i inserted a third container div in which all the texts are stored and after svg is loaded they are positioned absolutly.
With every div I added the "pan-tween" and even the drawing performance decreased to a Point that is just too low.
I am searching for way to bring the performance back to a level that is acceptable for the user. One of my ideas is to set text divs to display : none, or visibility : hidden, as long as they are not displayed actually. Another option is to tween only svg and canvas, after this is finished placing the text-div-container in one step. But I am currently not sure which solution is better, or if there isn't something much better. So if anybody has an Idea, please let me know.
Thanks for reading!
Greetings Philipp

Try to pan the outer "text div" in intervals(say 10ms or 50ms). I this with a lot with rendering, in HTML usually I use greater values like 100ms or 150ms(I use to do this with canvas).
Didn't understand if you pan the outer div or all the "text divs".