I have an absolutely positioned leading line within a relatively positioned div. I need to move the leading line horizonatally as the mouse moves using d3. Since d3.event requires the elements to be positioned within g elements, I am trying to use d3.mouse to move the leading line. However, the dragging behaviour is very erratic and flickers too much. I cannot seem to figure out what is causing this.
var drag = d3.behavior
.drag()
.on('drag', function(event) {
dragMoveNew(this);
})
d3.select(".grid").call(drag);
function dragMoveNew(elem) {
var x = d3.mouse(elem)[0];
$(elem).css('left', x);
}
Here is the jsfiddle link
https://jsfiddle.net/u4koenra/
Use d3.event.x
function dragMoveNew(elem) {
//var x = d3.mouse(elem)[0];
var x = d3.event.x;
$(elem).css('left', x);
}
Related
In this jsFiddle I have a Raphael canvas with a line/path where the user can drag it.
Problem is that the exact top pixel of the mouse pointer has to be on the line to be able to drag it. I need Raphael to be more "forgiving" and let the user drag the line if it touches the top, say, 3 pixels of the pointer.
I added mouseover/mouseout events to actually tell when the mouse is over the line, otherwise is very difficult to know.
So the question is: is there a way to drag the line without having to accurately position the mouse pointer?
var paper = Raphael("canvas", 600, 600);
var line = this.paper.path('M10 10 L50 50');
var start = function () {
this.odx = 0;
this.ody = 0;
},
move = function (dx, dy) {
this.translate(dx - this.odx, dy - this.ody);
this.odx = dx;
this.ody = dy;
},
up = function () {};
line.drag(move, start, up);
line.mouseover(function(e) {
line.attr('stroke', 'red');
});
line.mouseout(function(e) {
line.attr('stroke', 'black');
});
The Raphael library creates an SVG element (not a CANVAS element) for drawing purposes, and drawing lines creates PATH elements within the SVG element.
I had some success by increasing the line width on hover. You do have to trigger the width change by at least moving the mouse over the line, but it is a lot easier to select afterwards. While the visual effect produced may not be perfect (some width flicking can occur) continuing the drag operation proceeds without problem.
You could try increasing the line width by either modifying the stroke-width attribute in the mouseover and mouseout handlers:
line.mouseover(function(e) {
line.attr('stroke', 'red');
line.attr('stroke-width', '9')
});
line.mouseout(function(e) {
line.attr('stroke', 'black');
line.attr('stroke-width', '1')
});
or by modifying the stroke-width styling when hovering over all path elements in CSS using
path:hover {
stroke-width: 9;
}
According to this question Raphael does not provide an abstraction of all possible CSS styling so it could use VML in XML documents. If you can live without IE 9 support and expect users to have a modern browser you may be interested in the following snippet which
increases the width of a line on mouseover by setting class name draggable, which sets a move cursor,
when a move is started replaces draggable with dragging ( which removes the width increase) and sets a move cursor over the svg container,
removes class draggable, but not dragging, on mouseout
cleans up classes and the cursor in the up function.
"use strict";
var container = document.getElementById("canvas");
var paper = Raphael("canvas", 600, 600);
var line = this.paper.path('M10 10 L50 50');
var start = function () {
this.odx = 0;
this.ody = 0;
},
move = function (dx, dy) {
this.translate(dx - this.odx, dy - this.ody);
this.odx = dx;
this.ody = dy;
if( this.node.classList.contains("draggable")) {
this.node.classList.replace("draggable", "dragging");
container.classList.add("moveCursor");
}
},
up = function (e) {
line.node.classList.remove("draggable", "dragging");
container.classList.remove("moveCursor");
};
line.drag(move, start, up);
line.mouseover(function(e) {
if(!e.target.classList.contains("dragging")) {
e.target.setAttribute("class", "draggable");
}
});
.draggable:hover {
stroke-width: 9;
stroke:red;
cursor: move;
}
path.dragging {
stroke: red;
}
.moveCursor{
cursor:move;
}
svg {
border: thin solid blue;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/raphael/2.1.0/raphael-min.js"></script>
<!-- body-html -->
<div id="canvas"></div>
The code is basically for demonstration - if you drag a line outside the SVG element you can't see it or grab it to drag back.
Some CSS rules (i.e. path.dragging) needed additional specificity to take priority over the defaults supplied by Raphael.
I need to develop 2 animations on a polygon:
automatic rotation of each segments
the polygon follows the mouse movements
I'm trying to do that with this code:
// onMouseMove
tool.onMouseMove = function (event) {
mousePoint = event.point;
};
// onFrame
view.onFrame = function (event) {
// Animation 1: Automatic circular rotation of each segment
for (var i = 0; i < polygon.segments.length; i++) {
var offsetRotation = new Point(Math.cos(event.time + i * 2), Math.sin(event.time + i * 2)).multiply(10);
polygon.segments[i].point = polygonCached.segments[i].point.add(offsetRotation);
}
// Animation 2: the polygon moves following the mouse movements with transition
var delta = mousePoint.subtract(polygon.position).divide(15);
polygon.position = polygon.position.add(delta);
};
Here is the whole code: https://codepen.io/anon/pen/YMgEEe?editors=0010
With the above code the automatic rotation of each segments works and the polygon doesn't follow the mouse at all and also without the transition.
Instead, commenting the automatic rotation animation it correctly follows the mouse with transition.
To check if transition works I move the mouse cursor outside of browser window and then go back from another point. Now you'll see no transition when the polygon moves.
Where I'm wrong?
Just move the polygonCached as well.
polygonCached.position = polygonCached.position.add(delta);
https://codepen.io/arthursw/pen/LvKPXo
The cached version of the polygon was not moving, so each time you rotated your points, their position was reset.
I'm currently building a menu that is also draggable and I'm using the following on each individual tab:
(mousedown)="dragging = false"
(mousemove)="checkMouseMove($event)"
(mouseup)="changeRoute('forms')"
Change Route looks like this:
changeRoute(routeName: string) {
// manual reset for dragging.
if (this.dragging) {
return;
}
Past this is just my routing and switch statement's that correctly will change route and apply styling etc.
Previously inside the mousemove event I just had dragging = true but the problem with this is that even the slightest movement will mean that a click does not occur when it's likely to be intended to.
My first instinct was that I need to add a buffer to the amount of space it will need to move to be called a drag but given the output events I'm not sure how to achieve this.
checkMouseMove(event) {
console.log(event);
}
This event provides me with the following output:
How can I use these events in conjunction with my checkMouseMove / Component to only change dragging after a reasonable amount of movement?
You can save the last mouse position and calculate the distance the cursor moved.
Based on this distance you can filter small and unwanted drags.
var lastEvent;
function checkMouseMove (event){
var dx = 0;
var dy = 0;
if (lastEvent) {
dx = event.clientX - lastEvent.clientX;
dy = event.clientY - lastEvent.clientY;
}
var d = Math.sqrt(Math.pow(dx, 2) + Math.pow(dy, 2));
if (d > 5) { /* handle mouse move here */ }
lastEvent = event;
}
You can also use any other non euclidean heuristics like Manhattan or Chebyshev.
Tldr; dragging the SVG causes it to rotate as well as translate.
I am trying to implement dragging and zooming events on an SVG group using D3 (v.4) as part of an Angular service.
this.unitGroup = this.svg.append('g')
.attr('id', 'unitGroup')
.call(this.drag)
.call(this.zoom);
Dragging translates the SVG.
drag = d3.drag()
.on('start', () => {
console.log('drag start');
this.setClickOrigin(d3.event);
})
.on('drag', (d, i, n) => {
const target = d3.select(n[i]).node() as any;
const m = target.getCTM();
const x = d3.event.x - this.clickOrigin.x;
const y = d3.event.y - this.clickOrigin.y;
this.setClickOrigin(d3.event);
this.translate(target, x, y);
});
While zooming rotates the SVG.
zoom = d3.zoom()
.on('zoom', (d, i, n) => {
const target = d3.select(n[i]).node() as any;
const m = target.getCTM();
const b = target.getBBox();
const dir = (d3.event.sourceEvent.deltaY > 0) ? 1 : -1;
this.rotate(target, dir);
});
My original code worked fine. However, integrating it into Angular has thrown up some problems.
The current problem is that when you drag the unitGroup it triggers the zoom event along with the drag event.
The expected behaviour is that:
'click-and-drag' translates the small, dark-grey box in the x and y dimensions.
'mouse-wheel-scroll' rotates the small, dark-grey box around its center.
Here is a Plunker: https://embed.plnkr.co/0GrGG7T79ubpjYa2ChYp/
Actually, what you are seeing here is the expected behaviour.
In D3, d3.zoom() handles not only the zoom but the panning as well. So, the mousemove is being handled by d3.drag() and by the zoom function as well.
As Bostock (D3 creator) once said:
combining these two behaviors* means that gesture interpretation is ambiguous and highly sensitive to position. (*zoom and drag)
Off the top of my head the simplest solution is just checking if you had a "real" zoom (mouse wheel) in the zoom function and, if you didn't (no mouse wheel), return:
if(!d3.event.sourceEvent.deltaY) return;
Here is your plunker with that change only: https://plnkr.co/edit/jz5X4Vm9wIzbKmTQLBAT?p=preview
I have a #wrapper div and a #grid div nested inside. currently I can scroll around with this function below.
getCursorPos : function(){
// set the empty cursor object
var cursor = {};
//get the offset from the left of the grid container
var grid
//offset loop
$(function getCursorPos(){
grid = $('#grid').offset();
setTimeout(getCursorPos, game.loopSpeed);
});
//continuosly get the position
var that = this;
$(document).mousemove(function(e){
//if game mode is menu exit
if(game.mode === 'menu'){
return;
}
// NOTE: this looks a litle over done but don't remove anything
// its like this because javascript uses floating points
// and so in order to line up to the nearest hunderedth I
// had to make the cursor and div position intergers by
// muliplying by ten. one the two are added I reduced them
// and rounded them.
that.x = Math.round(((e.pageX * 10) - (grid.left * 10)) / 10);
that.y = Math.round(((e.pageY * 10) - (grid.top * 10)) / 10);
});
},
the problem is that the mouse coordinates only update when the mouse moves. is there any way to get the coordinates with out moving the mouse?
You always have the latest up-to-date coordinates of the mouse from the last mouse move, clarify why those are not useful to you.