examples - fabricjs mobile

Mueve el objeto dentro del límite del lienzo

Question

Estoy tratando de limitar el objeto en movimiento dentro del lienzo, pero tengo dificultad para mover el objeto con un área límite en la parte superior e izquierda y cuando escala el objeto con un tamaño grande, no puedo limitar el objeto en movimiento Lado izquierdo y superior del lienzo.

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)
        }
});

Answer 1

Acabo de modificar el código de Balaji un poco funciona mejor ahora

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);
    }});

Answer 2

Aquí puedes encontrar la solución: -

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/

Answer 3

Como necesitaba esto, aquí está mi función con exceso de trabajo basada en el código de Balaji para establecer un desplazamiento, por lo que los objetos solo se pueden mostrar parcialmente dentro del lienzo.

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);
      }
});      

Answer 4

Solo agregue el código a continuación en su archivo js y cambie el valor de la escala X (izquierda) e Y (arriba) de acuerdo con la altura y el ancho de su lienzo.

// 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

Answer 5

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);
        }
});