这是基于 gco 的答案，更新后可与 FabricJS 1.5.0 一起使用，并进行了以下改进：
JS小提琴：https : //jsfiddle.net/aphillips8/31qbr0vn/1/
var canvas = new fabric.Canvas('canvas'),
canvasWidth = document.getElementById('canvas').width,
canvasHeight = document.getElementById('canvas').height,
counter = 0,
rectLeft = 0,
snap = 20; //Pixels to snap
canvas.selection = false;
plusrect();
plusrect();
plusrect();
function plusrect(top, left, width, height, fill) {
var rect = new fabric.Rect({
top: 300,
name: 'rectangle ' + counter,
left: 0 + rectLeft,
width: 100,
height: 100,
fill: 'rgba(' + (Math.floor(Math.random() * 256)) + ',' + (Math.floor(Math.random() * 256)) + ',' + (Math.floor(Math.random() * 256)) + ', 0.75)',
lockRotation: true,
originX: 'left',
originY: 'top',
cornerSize: 15,
hasRotatingPoint: false,
perPixelTargetFind: true,
minScaleLimit: 1,
maxWidth: canvasWidth,
maxHeight: canvasHeight
});
rect.custom = {};
rect.custom.counter = counter;
canvas.add(rect);
counter++;
rectLeft += 200;
}
function findNewPos(distX, distY, target, obj) {
// See whether to focus on X or Y axis
if(Math.abs(distX) > Math.abs(distY)) {
if (distX > 0) {
target.setLeft(obj.getLeft() - target.getWidth());
} else {
target.setLeft(obj.getLeft() + obj.getWidth());
}
} else {
if (distY > 0) {
target.setTop(obj.getTop() - target.getHeight());
} else {
target.setTop(obj.getTop() + obj.getHeight());
}
}
}
canvas.on('object:moving', function (options) {
// Sets corner position coordinates based on current angle, width and height
options.target.setCoords();
// Don't allow objects off the canvas
if(options.target.getLeft() < snap) {
options.target.setLeft(0);
}
if(options.target.getTop() < snap) {
options.target.setTop(0);
}
if((options.target.getWidth() + options.target.getLeft()) > (canvasWidth - snap)) {
options.target.setLeft(canvasWidth - options.target.getWidth());
}
if((options.target.getHeight() + options.target.getTop()) > (canvasHeight - snap)) {
options.target.setTop(canvasHeight - options.target.getHeight());
}
// Loop through objects
canvas.forEachObject(function (obj) {
if (obj === options.target) return;
// If objects intersect
if (options.target.isContainedWithinObject(obj) || options.target.intersectsWithObject(obj) || obj.isContainedWithinObject(options.target)) {
var distX = ((obj.getLeft() + obj.getWidth()) / 2) - ((options.target.getLeft() + options.target.getWidth()) / 2);
var distY = ((obj.getTop() + obj.getHeight()) / 2) - ((options.target.getTop() + options.target.getHeight()) / 2);
// Set new position
findNewPos(distX, distY, options.target, obj);
}
// Snap objects to each other horizontally
// If bottom points are on same Y axis
if(Math.abs((options.target.getTop() + options.target.getHeight()) - (obj.getTop() + obj.getHeight())) < snap) {
// Snap target BL to object BR
if(Math.abs(options.target.getLeft() - (obj.getLeft() + obj.getWidth())) < snap) {
options.target.setLeft(obj.getLeft() + obj.getWidth());
options.target.setTop(obj.getTop() + obj.getHeight() - options.target.getHeight());
}
// Snap target BR to object BL
if(Math.abs((options.target.getLeft() + options.target.getWidth()) - obj.getLeft()) < snap) {
options.target.setLeft(obj.getLeft() - options.target.getWidth());
options.target.setTop(obj.getTop() + obj.getHeight() - options.target.getHeight());
}
}
// If top points are on same Y axis
if(Math.abs(options.target.getTop() - obj.getTop()) < snap) {
// Snap target TL to object TR
if(Math.abs(options.target.getLeft() - (obj.getLeft() + obj.getWidth())) < snap) {
options.target.setLeft(obj.getLeft() + obj.getWidth());
options.target.setTop(obj.getTop());
}
// Snap target TR to object TL
if(Math.abs((options.target.getLeft() + options.target.getWidth()) - obj.getLeft()) < snap) {
options.target.setLeft(obj.getLeft() - options.target.getWidth());
options.target.setTop(obj.getTop());
}
}
// Snap objects to each other vertically
// If right points are on same X axis
if(Math.abs((options.target.getLeft() + options.target.getWidth()) - (obj.getLeft() + obj.getWidth())) < snap) {
// Snap target TR to object BR
if(Math.abs(options.target.getTop() - (obj.getTop() + obj.getHeight())) < snap) {
options.target.setLeft(obj.getLeft() + obj.getWidth() - options.target.getWidth());
options.target.setTop(obj.getTop() + obj.getHeight());
}
// Snap target BR to object TR
if(Math.abs((options.target.getTop() + options.target.getHeight()) - obj.getTop()) < snap) {
options.target.setLeft(obj.getLeft() + obj.getWidth() - options.target.getWidth());
options.target.setTop(obj.getTop() - options.target.getHeight());
}
}
// If left points are on same X axis
if(Math.abs(options.target.getLeft() - obj.getLeft()) < snap) {
// Snap target TL to object BL
if(Math.abs(options.target.getTop() - (obj.getTop() + obj.getHeight())) < snap) {
options.target.setLeft(obj.getLeft());
options.target.setTop(obj.getTop() + obj.getHeight());
}
// Snap target BL to object TL
if(Math.abs((options.target.getTop() + options.target.getHeight()) - obj.getTop()) < snap) {
options.target.setLeft(obj.getLeft());
options.target.setTop(obj.getTop() - options.target.getHeight());
}
}
});
options.target.setCoords();
// If objects still overlap
var outerAreaLeft = null,
outerAreaTop = null,
outerAreaRight = null,
outerAreaBottom = null;
canvas.forEachObject(function (obj) {
if (obj === options.target) return;
if (options.target.isContainedWithinObject(obj) || options.target.intersectsWithObject(obj) || obj.isContainedWithinObject(options.target)) {
var intersectLeft = null,
intersectTop = null,
intersectWidth = null,
intersectHeight = null,
intersectSize = null,
targetLeft = options.target.getLeft(),
targetRight = targetLeft + options.target.getWidth(),
targetTop = options.target.getTop(),
targetBottom = targetTop + options.target.getHeight(),
objectLeft = obj.getLeft(),
objectRight = objectLeft + obj.getWidth(),
objectTop = obj.getTop(),
objectBottom = objectTop + obj.getHeight();
// Find intersect information for X axis
if(targetLeft >= objectLeft && targetLeft <= objectRight) {
intersectLeft = targetLeft;
intersectWidth = obj.getWidth() - (intersectLeft - objectLeft);
} else if(objectLeft >= targetLeft && objectLeft <= targetRight) {
intersectLeft = objectLeft;
intersectWidth = options.target.getWidth() - (intersectLeft - targetLeft);
}
// Find intersect information for Y axis
if(targetTop >= objectTop && targetTop <= objectBottom) {
intersectTop = targetTop;
intersectHeight = obj.getHeight() - (intersectTop - objectTop);
} else if(objectTop >= targetTop && objectTop <= targetBottom) {
intersectTop = objectTop;
intersectHeight = options.target.getHeight() - (intersectTop - targetTop);
}
// Find intersect size (this will be 0 if objects are touching but not overlapping)
if(intersectWidth > 0 && intersectHeight > 0) {
intersectSize = intersectWidth * intersectHeight;
}
// Set outer snapping area
if(obj.getLeft() < outerAreaLeft || outerAreaLeft == null) {
outerAreaLeft = obj.getLeft();
}
if(obj.getTop() < outerAreaTop || outerAreaTop == null) {
outerAreaTop = obj.getTop();
}
if((obj.getLeft() + obj.getWidth()) > outerAreaRight || outerAreaRight == null) {
outerAreaRight = obj.getLeft() + obj.getWidth();
}
if((obj.getTop() + obj.getHeight()) > outerAreaBottom || outerAreaBottom == null) {
outerAreaBottom = obj.getTop() + obj.getHeight();
}
// If objects are intersecting, reposition outside all shapes which touch
if(intersectSize) {
var distX = (outerAreaRight / 2) - ((options.target.getLeft() + options.target.getWidth()) / 2);
var distY = (outerAreaBottom / 2) - ((options.target.getTop() + options.target.getHeight()) / 2);
// Set new position
findNewPos(distX, distY, options.target, obj);
}
}
});
});