Raphael - Transform after Serialization - svg

I am using Raphael to draw some paths. Each path has an associated rectangle [container] the size and position of the bounding box. I am using the container for dragging both shapes.
In the move callback, I update the both positions so they both move together.
This all works great until I serialize. I am only serializing the path, then creating the container on the fly after deserialization.
Immediately after converting to json and back, things look fine. I can print out the current transform of the path and it looks correct. Doing any transform on the path after this results in the path being reset and moved to 0,0.
Here is a fiddle that shows the problem.
If you move the rect, you can see both objects move together.
If you click 'Save/Load', things look fine, and the path prints the same.
If you now drag, the path gets reset to 0,0. Printing shows the transform has been reset from 0,0.
I am trying to find out how to make the path move as it did before serialization. Is something getting lost in the process? Or is there an internal state that needs to be updated?

Raphael.JSON serialises data stored in the elements. It does not preserve temporary data stored in the paper object so something does indeed get lost in the process when calling R.clear(). For example drag events bound to elements are not preserved.
However the main issue here is with your drag function, notice how dragging the square a second time applies the transformation from the top left of the paper. I suggest using Raphael.FreeTransform (which you already included in the Fiddle) to handle this.
I wrote both Raphael.JSON and Raphael.FreeTransform plugins and have struggled with the same issues. I'm currently working on an application that lets you save save and restore the state of the paper (similar to what you're doing) and it works fine. If you need any help feel free to open an issue on Github.

You need to capture the initial transform offsets of your elements when the drag starts and use those as the basis for your drag-move transforms. Consider the following:
var start_x, start_y;
cont.drag(function(x, y, e)
{
p.transform('t' + ( start_x + x ) + ',' + ( start_y + y ) );
cont.transform('t' + ( start_x + x ) + ',' + ( start_y + y ) );
},
function( x, y )
{
var start_bbox = p.getBBox();
start_x = start_bbox.x;
start_y = start_bbox.y;
console.log("Drag start at %s,%s", start_x, start_y );
} );
I've staged this in a fiddle located here.
Unfortunately, there is still an issue with the path -- it's offset is being incremented by the difference between it's bounding box y value and the y axis (a difference of 12, to be precise) each time drag is used. I'm not sure where that's coming from exactly.

Related

noUISlider - Any way to place labels within the connect segments

I have a noUiSlider with several handles to allow specifying several contiguous date periods (example = Feb to Apr, May to July, and Aug to Sept). Ideally I would like to have labels that appear centered on the connect divisions to describe what each period relates to (ex. "Current Period", "Next Period"). I was thinking I could do this by setting a centered background image on the noUi-connect divisions.
However, the noUi-connect divisions use transform (translate/scale) styling which results in my background images being scaled which I do not want.
I also thought maybe I could revise the javascript to generate an outer division around each nonUi-connect division, and I would apply the background onto the outer division instead - but I was unable to get the background from the outer division to appear.
Any other ways I could accomplish this? The only other thing I can think of it to have floating divisions defined outside of the noUiSlider object which I would need to reposition whenever I detect changes in the handle positions.
You can add an element outside of the connects and absolutely position it.
A quick version for a slider with two handles (showing the value for the first handle):
var origin = slider.querySelector('.noUi-connects');
var node = document.createElement('div');
node.style.textAlign = 'center';
node.style.position = 'absolute';
node.style.zIndex = '10';
node.style.fontSize = '10px';
origin.appendChild(node);
slider.noUiSlider.on('update', function(values, handle, unencoded, tap, positions) {
node.style.left = positions[0] + '%';
node.style.right = (100 - positions[1]) + '%';
node.innerText = values[0];
});
Just realized another approach is to set the innerHtml of the specific noUi-connect divisions to my label values. Simpler than playing with background images.
But the transform styling still affects the labels, so the end result is not better. Maybe I can load the innerHtml with an inner division that somehow ignores the transform settings but I haven't figure out how to do that yet. transform: none does not make any difference.

Why isn't my path2d position updating?

I created a new path2d following the instructions in the my first game article: http://docs.godotengine.org/en/3.0/getting_started/step_by_step/your_first_game.html
I wanted to move the "box" on screen so that I could see how the mobs spawn in, but when I ran the scene, it stayed off screen.
I created a new path2d, centered this one in the middle of the screen, and it works like I wanted it to, but now I moving this one in the editor doesn't update the position in game.
What's going on?
Thanks
func _on_mobtimer_timeout():
$mobtimer.wait_time = 0.1 + randf() / 2
$mobspawn/moblocation.set_offset(randi())
var mob = Mob.instance()
add_child(mob)
var direction = $mobspawn/moblocation.rotation + PI/2
mob.position = $mobspawn/moblocation.position
direction += rand_range(-PI/8, PI/8)
mob.rotation = direction
mob.set_linear_velocity(Vector2(rand_range(200, 200 + score * 30), 0).rotated(direction))
A Node2D's position property is relative to it's parent's position. The code from the Dodge The Creeps tutorial assumes that MobPath is located at 0, 0 and fails when that assumption is false.
In your case you are taking a MobSpawnLocation's position relative to MobPath and then setting it as the new Mob's global position.
Luckily Node2D's have another property that we can use in these circumstances global_position. It can be used like this:
mob.position = $mobspawn/moblocation.global_position
http://docs.godotengine.org/en/stable/classes/class_node2d.html#member-variables
This isn't a full solution, but I found a weird workaround. Instead of changing the position in the editor, if you use the nodes on the orange box (at the intersection of orange and blue), you can kind of alternate to move the box around.

OpenCV Seamless Cloning shift position after finish the process

I am trying to used the seamsless cloning to blend to image together.
but I notice that after using the seamsless clone function the area in the
mask that I want to transfer is shift upward. So I have a question that
is this a normal behaviour of the seamsless clone function or it is a bug
on my implementation.
Here are the Source photo
Here are the destination photo
Here are the result photo
I encountered similar situation. Moreover, like #JoshuaCWebDeveloper noted, this shift disappeared when all one mask is used. Nevertheless, I got a fix for this. What I did is this. I cropped valid mask (non-zero sub-section) out using cv2.boundingRect. So my source image and mask image are reduced to a smaller size, while center is now calculated from boundingRect outputs (Since reference point is marked on destination image). This way, error got solved/shift got ridden.
(Based on the answer posted by Fractalic Forieu) You can achieve the same result without reducing the image size.
Instead of using the image center:
center = (width // 2, height // 2)
poissonImage = cv2.seamlessClone(srcImage, dstImage, maskImage, center)
use the center of the bounding rect:
monoMaskImage = cv2.split(maskImage)[0] # reducing the mask to a monochrome
br = cv2.boundingRect(monoMaskImage) # bounding rect (x,y,width,height)
centerOfBR = (br[0] + br[2] // 2, br[1] + br[3] // 2)
poissonImage = cv2.seamlessClone(srcImage, dstImage, maskImage, centerOfBR )

D3js: finding path's bounding box (without getBBox() )?

The following code works on Chromium :
var node = window.d3.selectAll('#L1 > *:nth-child(2)');
var bbox = node.node().getBBox();
console.log(bbox) // {height: 44, width: 44, y: -13, x: 144}
but not with nodejs + jsdom:
"TypeError: Object [ PATH ] has no method 'getBBox' "
M. Bostock pointed out that JSDOM doesn't support getBBox()
What D3js replacement to use to get the bounding box of #L1 > *:nth-child(2) ?
Past efforts lead me there : getBBox() based fiddle
Path's bounding box
Digging straight into the element's path data d="..." should work. An svg line is basically a set of x,y points. Assuming absolute coordinates without translation nor big bezier curves, which is the case of my D3js-generated svg lines, I'am finding in this data the min and max values for both x and y.
To do so, I get the d="..." svg line or multilines code. For simplicity sake, I rudely removes possible relative jumps such h30 or v20 since I never saw any in my D3js output, then clean out letters (aka svg commands : M,L,H,V,C,S,Q,T,A,Z), simplify the spaces and line jumps, then split by the remaining spaces. I get a clean arrays of coordinates.
Important to note, my selector directly target a single non-translated path.
var getBBox = function(selector){
var xmin, xmax, ymin, ymax,p;
// clean up path
var t = d3.select(selector).attr("d"); // get svg line's code
console.log(t)
t = t.replace(/[a-z].*/g," ") // remove relative coords, could rather tag it for later processing to absolute!
.replace(/[\sA-Z]+/gi," ").trim().split(" "); // remove letters and simplify spaces.
console.log(t)
for(var i in t){ // set valid initial values
if(t[i].length>1){
p = t[i].split(",");
xmin = xmax = p[0]; ymin = ymax = p[1]; }
}
for(var i in t){ // update xmin,xmax,ymin,ymax
p = t[i].split(",");
if(!p[1]){ p[0]=xmin; p[1] = ymin;} // ignore relative jumps such h20 v-10
xmin = Math.min(xmin, p[0]);
xmax = Math.max(xmax, p[0]);
ymin = Math.min(ymin, p[1]);
ymax = Math.max(ymax, p[1]);
} return [[xmin,ymax],[xmax,ymin]]; // [[left, bottom], [right, top]] as for https://github.com/mbostock/d3/wiki/Geo-Paths#bounds
}
var bb = getBBox("path");
JSfiddle DEMO
Groups bounding boxes
For groups of multiple paths, you may want to traverse the svg DOM to loop upon each single path of the group in order to update xmin, ymin, xmax, ymax.
Translated elements
To handle translated elements, adapt further.
Alternatives
Other better approaches may exist. Remember to check if getBBox() and getBoundingClientRect() are available in your context, since they are native and very convenient.
The reason why getBBox/getBoundingClientRect/getClientRect does not work in NodeJS+JSDOM is that calculating these values of an SVG (or HTML) element involves massive amounts of computation.
First, all CSS code in <style> elements must be parsed (which is already not trivial). Then the CSS selectors, cascading and inheritance rules must be applied to know what size, position or line width an element has. And even after you know all style property values, you need to do some non-trivial maths to calculate the bounding boxes: definition of different SVG transform functions, compositions of these, bounding boxes of SVG primitives and Bezier curves. Browsers support all of these (they have to, in order to draw the element), but JSDOM is simply not meant for all of these.
But fortunately, canvg is a JavaScript implementation of most of SVG, which uses a <canvas> element to draw the image. It does support most of the above, and although it does not have an interface for giving you those data, fortunately it has very nice (and MIT licensed) code, so hopefully you can copy and reuse parts of it. As of now, the code is written in a single file, and it has CSS parsing, applying cascading rules, path data parsing, definitions of SVG transforms, applying transformations, and bezier curve bounding box calculation. That is, almost everything you need to calculate bounding boxes :) It does not, however, support CSS selectors, but it can reuse another library. But unfortunately, as far as I can tell, canvg is not ready for running in NodeJS, you probably need some tweaks.
There is, however canvgc, an SVG to JS compiler, which contains an older version of canvg, and it is capable of running in NodeJS. So it is easier to start with that.

How to right/end align text along an textPath inside an arc using d3.js?

Here's the fiddle: http://jsfiddle.net/DevChefOwen/CZ6Dp/
var text = g.append("text")
.style("font-size",30)
.style("fill","#000")
.attr("dy",0)
.append("textPath")
.attr("xlink:href","#yyy")
.style("text-anchor","left") // using "end", the entire text disappears
.text("some text");
I've tried a number of different things to no avail. The left align is the easy part. If you did a middle, though, you see only "text" instead of "some text", implying that "some" is just hidden because it went "out of span" for the given arc.
If, however, I added:
.attr("startOffset","39%")
(as in here: http://jsfiddle.net/DevChefOwen/2H99c/)
It would look right aligned, but outside of programmatically trying to get the width/height of the text element and look for sharp changes in width/height (which seems wrong and likely error-prone), I can't seem to find a way to right align the text.
I've also tried using an SVG path (essentially a curved arc line) and the same disappearing act happens with the text when "text-anchor" is set to "left".
Thanks ahead for your time!
The question is somewhat confusing matters. The issue isn't aligning text at the end of the path -- that's easy to do with "text-anchor"="end" and "startOffset"="100%".
However, using those settings with the path created by the d3 arc function, you end up with the text cornering around the end of the inside curve and the left straight edge, to the end of the path as defined by the arc function:
http://jsfiddle.net/CZ6Dp/8/
The real issue is that the path that you want the text to be aligned along (the outside arc of the shape) is only one segment of the path that defines the shape.
(By the way, "left" and "right" are not valid values for the "text-anchor" property, and will just be ignored).
The answer by #defghi1977 gives one way to approach the problem, by figuring out the length of the path segment that you do want to use and adjusting the start offset accordingly.
Another way to approach the problem is to create a separate path (not drawn on screen) that represents only the part of the path that you want to be used for positioning text.
There are a number of possible ways to create a path that only represents the outside arc (some example code here). #defghi1977's approach of grabbing it from the existing path with regular expressions is probably the most efficent for your situation. But instead of just creating a temporary element to calculate a length, I actually have to add the new path to the DOM so it can be used as the reference path for the <textPath> element. (Which I suppose is the downside to this approach -- twice as many DOM elements!)
var path = g.append("svg:path")
.attr("d", arct)
.style("fill","#ccc")
.attr("transform", "translate("+cfg.w/2+","+cfg.h/2+")")
.each(function(d,i) {
var justArc = /(^.+?)L/;
//grab everything up to the first Line statement
var thisSelected = d3.select(this);
var arcD = justArc.exec( thisSelected.attr("d") )[1];
defs.append("path")
.attr("id", "yyy") //normally the id would be based on the data or index
.attr("d", arcD)
.attr("transform", thisSelected.attr("transform") );
//if you can avoid using transforms directly on the path element,
//you'll save yourself having to repeat them for the text paths...
});
var text = g.append("text")
.style("font-size",30)
.style("fill","#000")
.attr("dy",0)
.append("textPath")
.attr("xlink:href","#yyy")
.style("text-anchor","end")
.attr("startOffset","100%")
.text("some text");
http://jsfiddle.net/CZ6Dp/9/
Again, factoring in the extra DOM load #defghi1977's method is probably slightly preferrable, although this version has the benefit of not being dependent on browser support for getTotalLength. But as far as I know that method is fairly well implemented.
So just consider this an alternate approach for completeness' sake.
This path is constructed by 4(or 5) path segments.
So, this probrem will be solved to get first arc path length.
But I don't know how to get sub path length by using d3.js, thus I use svgdom directly.
I tried to fix your code. If this code is not what you hope, I'm sorry.
path-anchor attribute to end.
define function to get startOffset value.
var path = g.append("svg:path")
.attr("id","yyy")
.attr("d", arct)
.style("fill","#ccc")
.attr("transform", "translate("+cfg.w/2+","+cfg.h/2+")");
var text = g.append("text")
.style("font-size",30)
.style("fill","#000")
.attr("dy",0)
.append("textPath")
.attr("xlink:href","#yyy")
//.style("text-anchor","left") // using "end", the entire text disappears
.attr("text-anchor", "end")
.text("some text")
.attr("startOffset",function(){
var d = document.getElementById("yyy").getAttribute("d");
var tmp = document.createElementNS("http://www.w3.org/2000/svg" ,"path");
//get the arc segment of path
var arc = d.match(/(^.+?)L/)[1];
tmp.setAttribute("d", arc);
//return offset position
return tmp.getTotalLength();
});
I think the confusion comes from the meaning of text-anchor - it's not "relative to where on the parent will I justify" but rather "what part of me should I align to the start".
You're right to try to use startOffset to move the origin. Since the outer radius of your path is longer than the inner radius, the correct start offset is a little more than half of the path (around 53%).
Just a little more twiddling with your settings and you should have it. Here's a fiddle with my interpretation of what you're looking for.

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