Canvas FabricJS中的高级捕捉
我是根据我的例子。它包括:Canvas FabricJS中的高级捕捉,canvas,fabricjs,Canvas,Fabricjs,我是根据我的例子。它包括: 角捕捉 咬边 对象可以重叠 对象完全包含在画布中 对象的大小不能大于画布区域 代码如下: window.canvas = new fabric.Canvas('fabriccanvas'); window.counter = 0; var newleft = 0, edgedetection = 20, //pixels to snap canvasWidth = document.getElementById('fabriccanvas').wi
- 角捕捉
- 咬边
- 对象可以重叠
- 对象完全包含在画布中
- 对象的大小不能大于画布区域
window.canvas = new fabric.Canvas('fabriccanvas');
window.counter = 0;
var newleft = 0,
edgedetection = 20, //pixels to snap
canvasWidth = document.getElementById('fabriccanvas').width,
canvasHeight = document.getElementById('fabriccanvas').height;
canvas.selection = false;
plusrect();
plusrect();
plusrect();
function plusrect(top, left, width, height, fill) {
window.canvas.add(new fabric.Rect({
top: 300,
name: 'rectangle ' + window.counter,
left: 0 + newleft,
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,
maxHeight: document.getElementById("fabriccanvas").height,
maxWidth: document.getElementById("fabriccanvas").width,
}));
window.counter++;
newleft += 200;
}
this.canvas.on('object:moving', function (e) {
var obj = e.target;
obj.setCoords(); //Sets corner position coordinates based on current angle, width and height
// Prevent object from leaving canvas
if(obj.getLeft() < edgedetection) obj.setLeft(0);
if(obj.getTop() < edgedetection) obj.setTop(0);
if((obj.getWidth() + obj.getLeft()) > (canvasWidth - edgedetection)) obj.setLeft(canvasWidth - obj.getWidth());
if((obj.getHeight() + obj.getTop()) > (canvasHeight - edgedetection)) obj.setTop(canvasHeight - obj.getHeight());
canvas.forEachObject(function (targ) {
activeObject = canvas.getActiveObject();
if(targ === activeObject) return;
// Standard snapping when within range
if(Math.abs(activeObject.oCoords.tr.x - targ.oCoords.tl.x) < edgedetection) {
activeObject.left = targ.left - activeObject.currentWidth;
}
if(Math.abs(activeObject.oCoords.tl.x - targ.oCoords.tr.x) < edgedetection) {
activeObject.left = targ.left + targ.currentWidth;
}
if(Math.abs(activeObject.oCoords.br.y - targ.oCoords.tr.y) < edgedetection) {
activeObject.top = targ.top - activeObject.currentHeight;
}
if(Math.abs(targ.oCoords.br.y - activeObject.oCoords.tr.y) < edgedetection) {
activeObject.top = targ.top + targ.currentHeight;
}
// Snap top/left together when moving up/down or side to side if within range
if(Math.abs(activeObject.top - targ.top) < edgedetection) {
activeObject.top = targ.top;
}
if(Math.abs(activeObject.left - targ.left) < edgedetection) {
activeObject.left = targ.left;
}
if(activeObject.intersectsWithObject(targ) && targ.intersectsWithObject(activeObject)) {
targ.set({ strokeWidth: 2, stroke: 'red' });
} else {
targ.set({ strokeWidth: 0, stroke: false });
}
if(!activeObject.intersectsWithObject(targ)) {
activeObject.set({ strokeWidth: 0, stroke: false });
}
});
});
window.canvas=newfabric.canvas('fabriccanvas');
window.counter=0;
var newleft=0,
edgedetection=20,//要捕捉的像素数
canvasWidth=document.getElementById('fabriccanvas').width,
canvasHeight=document.getElementById('fabriccanvas').height;
canvas.selection=false;
plusrect();
plusrect();
plusrect();
功能加减(顶部、左侧、宽度、高度、填充){
window.canvas.add(new fabric.Rect({
排名:300,
名称:“矩形”+window.counter,
左:0+新左,
宽度:100,
身高:100,
填充:'rgba(+(Math.floor(Math.random()*256))+','+(Math.floor(Math.random()*256))+','+(Math.floor(Math.random()*256))+',0.75',
是的,
原文:“左”,
原创:“top”,
尺寸:15,
hasRotatingPoint:false,
perPixelTargetFind:对,
最低限额:1,
maxHeight:document.getElementById(“fabriccanvas”).height,
maxWidth:document.getElementById(“fabriccanvas”).width,
}));
window.counter++;
newleft+=200;
}
this.canvas.on('object:moving',function(e){
var obj=e.target;
obj.setCoords();//基于当前角度、宽度和高度设置角点位置坐标
//防止对象离开画布
if(obj.getLeft()(canvasWidth-edgedetection))obj.setLeft(canvasWidth-obj.getWidth());
if((obj.getHeight()+obj.getTop())>(canvasHeight-edgedetection))obj.setTop(canvasHeight-obj.getHeight());
canvas.forEachObject(函数(targ){
activeObject=canvas.getActiveObject();
if(target==activeObject)返回;
//在范围内时的标准捕捉
if(Math.abs(activeObject.oCoords.tr.x-target.oCoords.tl.x)
我想知道的是,是否可以扩展此功能以添加以下功能:
- 动态捕捉。在初始捕捉后继续拖动对象将暂时禁用捕捉,直到对象停止移动。例如,如果我将一个长方体拖动到另一个长方体旁边,它们在范围内时将捕捉在一起。但是,如果继续移动第一个长方体,我可以将其“放置”在捕捉范围内但未与另一个长方体对齐的位置
- 当选定对象在另一个对象的范围内时,显示参考线。目前,我们在目标对象周围添加了一个边框,但是最好显示向外延伸(可能延伸到画布边缘)的指导方针,以便更容易地可视化目标对象的边界