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キャンバス境界の制限内でオブジェクトを移動

キャンバス内で移動するオブジェクトを制限しようとしていますが、上部と左側に制限領域があるオブジェクトを移動するのが困難になっています。大きなサイズでオブジェクトを拡大縮小すると、移動するオブジェクトを制限することができませんキャンバスの左側と上側

canvas.observe("object:moving", function(e){
      var obj = e.target;
         // if object is too big ignore
        if(obj.currentHeight > obj.canvas.height || obj.currentWidth > obj.canvas.width){
            return;
        }

        var halfw = obj.currentWidth/2;
        var halfh = obj.currentHeight/2;
        var bounds = {tl: {x: halfw, y:halfh},
            br: {x: obj.canvas.width-halfw, y: obj.canvas.height-halfh}
        };

        // top-left  corner
        if(obj.top < bounds.tl.y || obj.left < bounds.tl.x){
            obj.top = Math.max(obj.top, bounds.tl.y);
            obj.left = Math.max(obj.left, bounds.tl.x )
        }


        // bot-right corner
        if(obj.top > bounds.br.y || obj.left > bounds.br.x){
            obj.top = Math.min(obj.top, bounds.br.y);
            obj.left = Math.min(obj.left, bounds.br.x)
        }
});
26
Sanjay Nakate

以下のコードをjsファイルに追加し、キャンバスの高さと幅に応じて、scale X(left) and Y(top))の値を変更します。

// canvas moving limit 

canvas.observe("object:moving", function(e){
      var obj = e.target;
         // if object is too big ignore

        var halfw = obj.currentWidth/2;
        var halfh = obj.currentHeight/2;
        var bounds = {tl: {x: halfw, y:halfh},
            br: {x: obj.canvas.width , y: obj.canvas.height }
        };

        // top-left  corner



            // alert("text");
        if(obj.top < bounds.tl.y || obj.left < bounds.tl.x){
            obj.top = Math.max(obj.top, '10'  );
            obj.left = Math.max(obj.left , '50' ) 
        }


        // bot-right corner
        if(obj.top > bounds.br.y || obj.left > bounds.br.x ){
            obj.top = Math.min(obj.top, '360'  );  
            obj.left = Math.min(obj.left, '470' )  
        }

});
// end canvas moving limit
5
Sanjay Nakate
canvas.on('object:moving', function (e) {
  var obj = e.target;
  // if object is too big ignore
  if(obj.currentHeight > obj.canvas.height || obj.currentWidth > obj.canvas.width){
    return;
  }
  obj.setCoords();
  // top-left  corner
  if(obj.getBoundingRect().top < 0 || obj.getBoundingRect().left < 0){
    obj.top = Math.max(obj.top, obj.top-obj.getBoundingRect().top);
    obj.left = Math.max(obj.left, obj.left-obj.getBoundingRect().left);
  }
  // bot-right corner
  if(obj.getBoundingRect().top+obj.getBoundingRect().height  > obj.canvas.height || obj.getBoundingRect().left+obj.getBoundingRect().width  > obj.canvas.width){
    obj.top = Math.min(obj.top, obj.canvas.height-obj.getBoundingRect().height+obj.top-obj.getBoundingRect().top);
    obj.left = Math.min(obj.left, obj.canvas.width-obj.getBoundingRect().width+obj.left-obj.getBoundingRect().left);
  }
});
56
Balaji

ここであなたは解決策を見つけることができます:-

var canvas = window._canvas = new fabric.Canvas('c');
canvas.selection = false;

fabric.Object.prototype.set({
    transparentCorners: false,
    cornerColor: 'red',
    cornerSize: 12,
    padding: 0
});
text = new fabric.Text('Sample',{
    top: canvas.height/2,
    left: canvas.width/2,
    fill: '#000000'
});

canvas.add(text);
canvas.setActiveObject(text);

canvas.observe('object:scaling', function (e) {
    var obj = e.target;
  if(obj.getHeight() > obj.canvas.height || obj.getWidth() > obj.canvas.width){
    obj.setScaleY(obj.originalState.scaleY);
    obj.setScaleX(obj.originalState.scaleX);        
  }
  obj.setCoords();
  if(obj.getBoundingRect().top - (obj.cornerSize / 2) < 0 || 
     obj.getBoundingRect().left -  (obj.cornerSize / 2) < 0) {
    obj.top = Math.max(obj.top, obj.top-obj.getBoundingRect().top + (obj.cornerSize / 2));
    obj.left = Math.max(obj.left, obj.left-obj.getBoundingRect().left + (obj.cornerSize / 2));    
  }
  if(obj.getBoundingRect().top+obj.getBoundingRect().height + obj.cornerSize  > obj.canvas.height || obj.getBoundingRect().left+obj.getBoundingRect().width + obj.cornerSize  > obj.canvas.width) {

    obj.top = Math.min(obj.top, obj.canvas.height-obj.getBoundingRect().height+obj.top-obj.getBoundingRect().top - obj.cornerSize / 2);
    obj.left = Math.min(obj.left, obj.canvas.width-obj.getBoundingRect().width+obj.left-obj.getBoundingRect().left - obj.cornerSize /2);    
  }
});

canvas.observe('object:moving', function (e) {
    var obj = e.target;
  if(obj.getHeight() > obj.canvas.height || obj.getWidth() > obj.canvas.width){
    obj.setScaleY(obj.originalState.scaleY);
    obj.setScaleX(obj.originalState.scaleX);        
  }
  obj.setCoords();
  if(obj.getBoundingRect().top - (obj.cornerSize / 2) < 0 || 
     obj.getBoundingRect().left -  (obj.cornerSize / 2) < 0) {
    obj.top = Math.max(obj.top, obj.top-obj.getBoundingRect().top + (obj.cornerSize / 2));
    obj.left = Math.max(obj.left, obj.left-obj.getBoundingRect().left + (obj.cornerSize / 2));    
  }
  if(obj.getBoundingRect().top+obj.getBoundingRect().height + obj.cornerSize  > obj.canvas.height || obj.getBoundingRect().left+obj.getBoundingRect().width + obj.cornerSize  > obj.canvas.width) {

    obj.top = Math.min(obj.top, obj.canvas.height-obj.getBoundingRect().height+obj.top-obj.getBoundingRect().top - obj.cornerSize / 2);
    obj.left = Math.min(obj.left, obj.canvas.width-obj.getBoundingRect().width+obj.left-obj.getBoundingRect().left - obj.cornerSize /2);    
  }
});

http://jsfiddle.net/jw1827fm/1/

7
Mullainathan

これが必要だったので、オフセットを設定するためのBalajiのコードに基づいた過労関数を次に示します。これにより、オブジェクトをキャンバス内で部分的にしか表示できなくなります。

canvas.on('object:moving', function (e) {
      var obj = e.target;

      // if object is too big ignore
      if(obj.currentHeight > obj.canvas.height || obj.currentWidth > obj.canvas.width){
          return;
      }        

      // set offset for moving out the canvas (20 % of object persists in canvas)
      var offsetWidth = obj.getBoundingRect().width * 0.8;
      var offsetHeight = obj.getBoundingRect().height * 0.8;

      obj.setCoords();        

      // top-left  corner
      if(obj.getBoundingRect().top < -offsetHeight || obj.getBoundingRect().left < -offsetWidth){
          obj.top = Math.max(obj.top, obj.top-(obj.getBoundingRect().top+offsetHeight));
          obj.left = Math.max(obj.left, obj.left-(obj.getBoundingRect().left+offsetWidth));
      }
      // bot-right corner
      if(obj.getBoundingRect().top+obj.getBoundingRect().height  > obj.canvas.height + offsetHeight || obj.getBoundingRect().left+obj.getBoundingRect().width  > obj.canvas.width + offsetWidth){
          obj.top = Math.min(obj.top, obj.canvas.height-obj.getBoundingRect().height+obj.top-obj.getBoundingRect().top+offsetHeight);
          obj.left = Math.min(obj.left, obj.canvas.width-obj.getBoundingRect().width+obj.left-obj.getBoundingRect().left+offsetWidth);
      }
});      
1
metamagikum

私はBalajiのコードを少し修正しただけで少しうまくいきます

canvas.on('object:moving', function (e) {
    var obj = e.target;

     // if object is too big ignore
    if(obj.getScaledHeight() > obj.canvas.height || obj.getScaledWidth() > obj.canvas.width){
        return;
    }        
    obj.setCoords();        
    // top-left  corner
    if(obj.getBoundingRect().top < 0 || obj.getBoundingRect().left < 0){
        obj.top = Math.max(obj.top, obj.top-obj.getBoundingRect().top);
        obj.left = Math.max(obj.left, obj.left-obj.getBoundingRect().left);
    }
    // bot-right corner
    if(obj.getBoundingRect().top+obj.getBoundingRect().height  > obj.canvas.height || obj.getBoundingRect().left+obj.getBoundingRect().width  > obj.canvas.width){
        obj.top = Math.min(obj.top, obj.canvas.height-obj.getBoundingRect().height+obj.top-obj.getBoundingRect().top);
        obj.left = Math.min(obj.left, obj.canvas.width-obj.getBoundingRect().width+obj.left-obj.getBoundingRect().left);
    }});
1
Surya T