animating svg pan when manually setting pan.x and pan.y - javascript

I have a dynamically generated svg image that I am using Ariutta's svg-pan-zoom plugin with. When I double click an svg image, I set pan.x = centerOfScreenX, and pan.y = centerOfScreenY to center the image in the middle of the screen. ie:
$('.svg').dblclick(function(){
zoom.pan({'x':centerOfScreenX, 'y':centerOfScreenY });
});
Currently this causes the image to just suddenly move to the center of the screen. Is there a way I can animate this change in pan position so that the image doubleclicked moves along a path to the center of the screen instead?
Bumbu suggested two solution paths (see answers below), and I have taken a stab at the first. My attempt did not work however, and I do not know why.
// centerOfScreenX and centerOfScreenY are the correct values that pan.x and
// pan.y should have to center the svg in the middle of the screen
// xInterval and yInterval break the distance between the current pan
// position and the desired pan position into 10 steps
var xInterval = (centerOfScreenX - pan.x)/10;
var yInterval = (centerOfScreenY - pan.y)/10;
while( pan.x !== centerOfScreenX && pan.y !== centerOfScreenY ){
if(pan.x !== centerOfScreenX){
pan({'x': pan.x + xInterval })
}
if(pan.y !== centerofScreenY){
pan({'y': pan.y + yInterval })
}
}
When I try to run this code, the window freezes and I can no longer interact with my app, unless i close the window and reload it. My guess is that I am somehow triggering an infinite loop.

Currently there is no solution to do animation in an easy way.
There is a similar question (about animating zoom). The answer from there (adjusted to this one) is:
Currently such functionality is not supported. You could do it in 2 ways:
Use a twin library (or write you own function) and just call pan in small iterations multiple times. This may be slow but it is what many libraries do when implementing animation (eg. jQuery).
Use SVG animateTransform element. It seems to be the right way. But it needs some work to get it done.
You can actually try to implement second solution by listening to zoom
events, canceling them and adding animateTransform manually to the SVG.
When your animation is done, call zoom again but this time don't
cancel it (necessary to update library inner state).
There is an ongoing discussion about next version of library that would be more extensible. This would allow to write plugins. Animation is one of the candidates. But it will take some time (few months) to do this.
If you'll be able to find a temporary solution - share it here or on github and we'll be happy to update the library or integrate it in next version.
Edit
I added a simple example how this kind of animation can be implemented.
You can find it in demo/simple-animation.html
I used a simple interval there. A more advanced version should take into account how much time passed since last interval call and send the right amount for pan. But even like this it works very well.
The library internally uses requestAnimationFrame so you can call panBy even every millisecond and it shouldn't block the browser.

Related

aframe - how enforce max/min camera tilt

I have six planes set up as cube with textures to display a 360-degree jpg set. I positioned the planes 1000 away and made them 2000 (plus a little because the photos have a tiny bit of overlap) in height and width.
The a-camera is positioned at origin, within this cube, with wasd controls set to false, so the camera is limited to rotating in place. (I am coding on a laptop, using mouse drag to move the camera.)
I also have a sphere (invisible), placed in between the camera and the planes, and have added an event listener to it. This seemed simpler than putting event listeners on each of the six planes.
My current problem is wanting to enforce minimum and maximum tilt limits. Following is the function "handleTilt" for this purpose. The minimum tilt allowed depends on the size of the fov.
function handleTilt() {
console.log("handleTilt called");
var sceneEl = document.querySelector("a-scene");
var elCamera = sceneEl.querySelector("#rotationCam");
var camRotation = elCamera.getAttribute('rotation');
var xTilt = camRotation['x'];
var fov = elCamera.getAttribute('fov');
var minTilt = -65 + fov/2;
camRotation['x'] = xTilt > minTilt ? xTilt : minTilt;
// enforce maximum (straight up)
if (camRotation['x'] > 90) {
camRotation['x'] = 90;
}
console.log(camRotation);
}
The event handler is set up in this line:
<a-entity geometry="primitive:sphere" id="clickSphere"
radius="50" position="0 0 0" mousemove="handleTilt()">
When I do this, a console.log call on #clickSphere shows the event handler exists. But it is never invoked when I run the program and move the mouse to drag the camera to different angles.
As an alternative, I made the #clickSphere listen for onClick as follows:
<a-entity geometry="primitive:sphere" id="clickSphere"
radius="50" position="0 0 0" onclick="handleTilt()">
The only change is "mousemove" to "onclick". Now, the "handleClick()" function executes with each click, and if the camera was rotated to a value less than the minimum, it is put back to the minumum.
One bizarre thing, though, after clicking and adjusting the rotation a few times, the program goes into a state where I can't rotate the camera down below the minimum any more. It is as if the mousemove listener had become engaged, even though the only listener coded is the onclick. I can't for the life of me figure out why this kicks in.
Would it be possible to get some advice as to what I might be doing wrong, or a plan for troubleshooting? I'm new to aframe and JavaScript.
An alternative plan for enforcing the min and max camera tilts in real time would also be an acceptable solution.
I just pushed out this piece on the docs for ya: https://aframe.io/docs/0.6.0/components/look-controls.html#customizing-look-controls
While A-Frame’s look-controls component is primarily meant for VR with sensible defaults to work across platforms, many developers want to use A-Frame for non-VR use cases (e.g., desktop, touchscreen). We might want to modify the mouse and touch behaviors.
The best way to configure the behavior is to copy and customize the current look-controls component code. This allows us to configure the controls how we want (e.g., limit the pitch on touch, reverse one axis). If we were to include every possible configuration into the core component, we would be left maintaining a wide array of flags.
The component lives within a Browserify/Webpack context so you’ll need to replace the require statements with A-Frame globals (e.g., AFRAME.registerComponent, window.THREE, AFRAME.constants.DEFAULT_CAMERA_HEIGHT), and get rid of the module.exports.
Can modify https://github.com/aframevr/aframe/blob/master/src/components/look-controls.js to hack in your min/max just for mouse/touch.

Circular canvas corners clickable in Chrome

I have two canvases. I have made them circular using border-radius. The 2nd is positioned inside the first one (using absolute position).
I have click events on both circles. If you click on inside canvas, the color at the point of the click is loaded in the outside canvas with opacity varying from white to the picked color and finally to black. If you click on outer canvas the exact color value at that point is loaded in the text-box at the bottom
I am unable to click in red zones (as shown in figure below) of the outer canvas when using chrome. I tried z-idex, arcs but nothing is helping me. But In Firefox everything is working fine.
Note: You can drag the picker object in the outer circle. But if you leave it in red zones, you would not be able to click it again in Chrome. Clicking in green zone will get you its control again
Code in this JSFiddle
Edit
I excluded all irrelevant code to make it easy. Now there is only a container having two canvas.
Filled simply with two distinct colors. Open following fiddle link in both chrome and firefox. Click on both cirles in different zones and see difference in chrome and firefox. I want them to behave in chrome as they do in firefox
Note I will ultimately draw an image in inner canvas.
Updated Fiddle Link
-
Your problem is because canvases currently are always rectangular, even if they don't look rectangular. Border radius makes the edges except the circle transparent, but it still doesn't stop events in Chrome on the corner areas. This is why you cannot click the bottom circle in those areas
I even tried putting it inside of a container that had a border-radius instead but the click event still goes through
With that being said, you have two options. You could either change your code to only use one canvas with the same type of layout, just drawing the background circle before the other each time. Essentially you'd draw a circle, draw your black to color to white gradient, use the xor operation to combine the two into one circle, then do the same with the rainbox gradient. You must draw the background circle first because canvas paints over the old layers every time
or
You could use javascript to only detect clicks in the circular area which takes just a little bit of math (: This solution is featured in edit below
In the future, CSS Shapes may allow canvases to be non-rectangular elements to be used, I'm actually not sure, but we don't have that capability yet at least
Edit
Alright, so after going through your code a bit it seems there are some things I should cover before I offer a solution
Setup all your finite variables outside of the functions that run every time. This means you don't put them (like radiuses, offsets, etc.) in the click function or something that runs often since they don't change
Your "radius"es are actually "diameter"s. The format of .rect goes .rect(x, y, width (diameter of circle), height (diameter of circle))
Almost always when overlaying canvases like you are you want to make them equal dimensions and starting position to prevent calculation error. In the end it makes it easier, doing all relative positioning with javascript instead of mixing it with CSS. In this case, however, since you're using border-radius instead of arc to make a circle, keep it like it is but position it using javascript ....
jQuery isn't needed for something this simple. If you're worried about any load speed I'd recommend doing it in vanilla javascript, essentially just changing the .click() functions into .onclick functions, but I left jQuery for now
You can declare multiple variables in a row without declaring var each time by using the following format:
var name1 = value1,
name2 = value2;
Variables with the same value you can declare like so:
var name1 = name2 = sameValue;
When children have position:absolute and you want it to be positioned relative to the parent, the parent can have position:relative, position:fixed, or position:absolute. I would think you'd want position:relative in this case
When you don't declare var for a variable it becomes global (unlessed chained with a comma like above). For more on that read this question
Now, onto the solution.
After talking with a friend I realized I could sort do the math calculation a lot easier than I originally thought. We can just calculate the center of the circles and use their radiuses and some if statements to make sure the clicks are in the bounds.
Here's the demo
After everything is set up correctly, you can use the following to detect whether or not it's in the bounds of each
function clickHandler(e, r) {
var ex = e.pageX,
ey = e.pageY,
// Distance from click to center
l = Math.sqrt(Math.pow(cx - ex, 2) + Math.pow(cy - ey, 2));
if(l > r) { // If the distance is greater than the radius
if(r === LARGE_RADIUS) { // Outside of the large
// Do nothing
} else { // The corner area you were having a problem with
clickHandler(e, LARGE_RADIUS);
}
} else {
if(r === LARGE_RADIUS) { // Inside the large cirle
alert('Outer canvas clicked x:' + ex + ',y:' + ey);
} else { // Inside the small circle
alert('Inner canvas clicked x:' + ex + ',y:' + ey);
}
}
}
// Just call the function with the appropriate radius on click
$(img_canvas).click(function(e) { clickHandler(e, SMALL_RADIUS); });
$(wheel_canvas).click(function(e) { clickHandler(e, LARGE_RADIUS); });
Hopefully the comments above and code make enough sense, I tried to clean it up as best as I could. If you have any questions don't hesitate to ask!

Kinetic js how to scale layer in a stage?

I want to add zoom feature my app . I use Kinetic js and somewhere I found solutions for this feature but I can't apply these solution for some reason . I tried to adapt the solutions but unsuccesful . I have many Kinetic.Layer , some of them will scale when zooming apply. my challenge is that : zoom will happen on mouse position . solution that I found gives me : layer.setPosition() after scaling . As I mentioned before , I must not use "layer.setPosition" I will do this as using stage.setPosition() but I couldn't calculate new x and y of position 100% accurately. Could anyone suggest me any solution way ?
What you really want to do when zooming is to set the scale.
You can set the scale for any layer, node, or the entire stage. Just do:
layer1.setScale(2,2); // this doubles the layer size from the original
This doesn't affect any other layer, so your overlay will stay in place.
In addition, you should also do:
layer1.setPosition(x,y); // this will move the layer to the fixed point you want.
All together you could do:
function zoom(){
var position = stage.getUserPosition();
layer1.setScale(2,2);
layer1.setPosition(position.x - layer2.getX(), position.y - layer2.getY()); //move the layer by an offset based on the second layer. This isn't exactly correct so it's something you have to experiment with.
}
Check out this: http://jsfiddle.net/TFU7Z/1/ Maybe is what you are looking for, I did not quite understand the question.
var zoom = function(e) {
var zoomAmount = 1;
layer.setScale(layer.getScale().x+zoomAmount)
layer.draw();
}
document.addEventListener("click", zoom, false)
Just click anywhere to zoom. You can attach the "click" event listener to whatever part of the stage / document you want.
These answers seems not to work awith the KineticJS 5.1.0. These do not work mainly for the signature change of the scale function:
stage.setScale(newscale); --> stage.setScale({x:newscale,y:newscale});
However, the following solution seems to work with the KineticJS 5.1.0:
JSFiddle: http://jsfiddle.net/rpaul/ckwu7u86/3/

Inner div inside an outer rotated div does not follow mouse in case dragging with jQuery UI

I have an inner div inside an outer div. The inner div is draggable and outer is rotated through 40 degree. This is a test case. In an actual case it could be any angle. There is another div called point which is positioned as shown in the figure. ( I am from a flash background . In Flash if I were to drag the inner div it would follow the mouse even if its contained inside an outer rotated div.) But in HTML the inner div does not follow the mouse as it can be seen from the fiddle. I want the div 'point' to exactly follow the mouse. Is this possible. I tried to work it using trignometry but could not get it to work.
http://jsfiddle.net/bobbyfrancisjoseph/kB4ra/8/
Here is my approach to this problem.
http://jsfiddle.net/2X9sT/21/
I put the point outside the rotated div. That way I'm assured that the drag event will produce a normal behavior (no jumping in weird directions). I use the draggable handler to attach the point to the mouse cursor.
In the drag event, I transform the drag offset to reflect the new values. This is done by rotating the offset around the outer div center in the opposite direction of the rotation angle.
I tested it and it seems to be working in IE9, Firefox, and Chrome.
You can try different values for angle and it should work fine.
I also modified the HTML so it is possible to apply the same logic to multiple divs in the page.
Edit:
I updated the script to account for containment behavior as well as cascading rotations as suggested in the comments.
I'm also expirementing with making the outer div draggable inside another div. Right now it is almost working. I just need to be able to update the center of the dragged div to fix the dragging behavior.
Try Dragging the red div.
http://jsfiddle.net/mohdali/kETcE/39/
I am at work now, so I can't do the job for you, but I can explain the mathematics behind the neatest way of solving your problem (likely not the easiest solution, but unlike some of the other hacks it's a lot more flexible once you get it implemented).
First of all you must realize that the rotation plugin you are using is applying a transformation to your element (transform: rotate(30deg)), which in turn is changed into a matrix by your browser (matrix(0.8660254037844387, 0.49999999999999994, -0.49999999999999994, 0.8660254037844387, 0, 0)).
Secondly it is necessary to understand that by rotating an element the axis of the child elements are rotate absolutely and entirely with it (after looking for a long time there isn't any real trick to bypass this, which makes sense), thus the only way would be to take the child out of the parent as some of the other answers suggest, but I am assuming this isn't an option in your application.
Now, what we thus need to do is cancel out the original matrix of the parent, which is a two step process. First we need to find the matrix using code along the following lines:
var styles = window.getComputedStyle(el, null);
var matrix = styles.getPropertyValue("-webkit-transform") ||
styles.getPropertyValue("-moz-transform") ||
styles.getPropertyValue("-ms-transform") ||
styles.getPropertyValue("-o-transform") ||
styles.getPropertyValue("transform");
Next the matrix will be a string as shown above which you would need to parse to an array with which you can work (there are jquery plugins to do that). Once you have done that you will need to take the inverse of the matrix (which boils down to rotate(-30deg) in your example) which can be done using for example this library (or your math book :P).
Lastly you would need to do the inverse matrix times (use the matrix library I mentioned previously) a translation matrix (use this tool to figure out how those look (translations are movements along the x and y axis, a bit like left and top on a relatively positioned element, but hardware accelerated and part of the matrix transform css property)) which will give you a new matrix which you can apply to your child element giving you the a translation on the same axis as your parent element.
Now, you could greatly simplify this by doing this with left, top and manual trigonometry1 for specifically rotations only (bypassing the entire need for inverse matrices or even matrices entirely), but this has the distinct disadvantage that it will only work for normal rotations and will need to be changed depending on each specific situation it's used in.
Oh and, if you are now thinking that flash was a lot easier, believe me, the way the axis are rotated in HTML/CSS make a lot of sense and if you want flash like behavior use this library.
1 This is what Mohamed Ali is doing in his answer for example (the transformOffset function in his jsFiddle).
Disclaimer, it has been awhile since I have been doing this stuff and my understanding of matrices has never been extremely good, so if you see any mistakes, please do point them out/fix them.
For Webkit only, the webkitConvertPointFromPageToNode function handles the missing behavior:
var point = webkitConvertPointFromPageToNode(
document.getElementById("outer"),
new WebKitPoint(event.pageX, event.pageY)
);
jsFiddle: http://jsfiddle.net/kB4ra/108/
To cover other browsers as well, you can use the method described in this StackOverflow answer: https://stackoverflow.com/a/6994825/638544
function coords(event, element) {
function a(width) {
var l = 0, r = 200;
while (r - l > 0.0001) {
var mid = (r + l) / 2;
var a = document.createElement('div');
a.style.cssText = 'position: absolute;left:0;top:0;background: red;z-index: 1000;';
a.style[width ? 'width' : 'height'] = mid.toFixed(3) + '%';
a.style[width ? 'height' : 'width'] = '100%';
element.appendChild(a);
var x = document.elementFromPoint(event.clientX, event.clientY);
element.removeChild(a);
if (x === a) {
r = mid;
} else {
if (r === 200) {
return null;
}
l = mid;
}
}
return mid;
}
var l = a(true),
r = a(false);
return (l && r) ? {
x: l,
y: r
} : null;
}
This has the disadvantage of not working when the mouse is outside of the target element, but it should be possible to extend the area it covers by an arbitrary amount (though it would be rather hard to guarantee that it covers the entire window no matter how large).
jsFiddle: http://jsfiddle.net/kB4ra/122/
This can be extended to apply to #point by adding a mousemove event:
$('#outer').mousemove(function(event){
var point = convertCoordinates(event, $("#outer"));
$("#point").css({left: point.x+1, top: point.y+1});
});
Note that I adjust the x and y coordinates of #point by 1px to prevent it from being directly underneath the mouse; if I didn't do that, then it would block dragging #inner. An alternative fix would be to add handlers to #point that detect mouse events and pass them on to whichever element is directly underneath #point (and stopPropagation, so that they don't run twice on larger page elements).
jsFiddle: http://jsfiddle.net/kB4ra/123/
It seems to me that if you do not rotate the div, the div exactly follows the mouse.
This might be a problem with the plugin..maybe you could simulate the draggable function corretly?
This basically will do what you need though it is buggy. Bind the drag event handler, intercept the ui object and modify it to use the offset X and Y of the parent element. All of the X, Y, top, left etc. are in those objects. I will try to get you a better example sometime when today when I get a bit more time. Good luck!
http://jsfiddle.net/kB4ra/107/
may be this is issue of your jquery library or you can check this by assigning z-order value of inner div and outer div make sure that you give higher number to inner div.

z in translate3d

Can anyone explain or point me to an example where the "z" in translate3d (webkit transform) is being used? I have successfully used translate3d(x,y,0) to get hardware accelerated 2D animations on mobile Safari, but now I’m trying to scale using the z parameter, but it does not seem to have any effect...
elem.style.WebkitTransform = 'translate3d(100px,0,0)'; // this works as expected
elem.style.WebkitTransform = 'translate3d(0,0,100)'; // nothing happens
elem.style.WebkitTransform = 'translate3d(0,0,100px)'; // nothing happens
elem.style.WebkitTransform = 'scale(1.2, 1.2)'; // works but slow on ios
Sidenote: I’m trying to build a small zoom script that works smoothly on ios.
I made this for you to show how webkit transform 3D works:
http://jsbin.com/iderag
I hope it help you. I'm guessing you don't have -webkit-perspective in your body or parent tag.
Remember to set the -webkit-perspective on the containing box. 800 is a good starting value. If the box disappears, reduce it, it's probably bigger than the viewport.
The Surfin' Safari blog has an article from when 3d transforms were first invented:
-webkit-perspective is used to give an illusion of depth; it
determines how things change size based on their z-offset from the z=0
plane. You can think of it as though you’re looking at the page from a
distance p away. Objects on the z=0 plane appear in their normal size.
Something at a z offset of p/2 (halfway between the viewer and the z=0
plane) will look twice as big, and something at a z offset of -p will
look half as big. Thus, large values give a little foreshortening
effect, and small values lots of foreshortening. Values between 500px
and 1000px give a reasonable-looking result for most content.
More here: http://www.webkit.org/blog/386/3d-transforms/

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