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我正在尝试使用fabric.js在画布上绘制免费绘图,但我无法在我身边自由绘制类似喷雾,圆形,纹理模式我使用此代码仅铅笔模式绘图工作但是当我选择喷雾和其他模式,该模式绘图为铅笔。

这是我的 HTML这是小提琴墨水

            <label for="drawing-mode-selector">Mode:</label>
            <select id="drawing-mode-selector">
              <option>Pencil</option>
              <option>Circle</option>
              <option>Spray</option>
              <option>Pattern</option>

              <option>hline</option>
              <option>vline</option>
              <option>square</option>
              <option>diamond</option>
              <option>texture</option>
            </select><br>
            <label for="drawing-line-width">Line width:</label>
            <input type="range" value="30" min="0" max="150" id="drawing-            line-width"><br>
            <label for="drawing-color">Line color:</label>
            <input type="color" value="#005E7A" id="drawing-color"><br>
            <label for="drawing-shadow-width">Line shadow width:</label>
            <input type="range" value="0" min="0" max="50" id="drawing-shadow-width"><br>
          </div>
        </li>

这是我的脚本代码

     var canvas = new fabric.Canvas('canvas')
     var drawingModeEl = document.getElementById('drawing-mode'),
      drawingOptionsEl = document.getElementById('drawing-mode-options'),
      drawingColorEl = document.getElementById('drawing-color'),
      drawingLineWidthEl = document.getElementById('drawing-line-width'),
      drawingShadowWidth = document.getElementById('drawing-shadow-width');

     drawingModeEl.onclick = function() {
    canvas.isDrawingMode = !canvas.isDrawingMode;
    if (canvas.isDrawingMode) {
      drawingModeEl.innerHTML = 'Cancel drawing mode';
      drawingOptionsEl.style.display = '';
    }
    else {
      drawingModeEl.innerHTML = 'Enter drawing mode';
      drawingOptionsEl.style.display = 'none';
    }
  };

  canvas.on('path:created', function() {
    updateComplexity();
  });

  if (fabric.PatternBrush) {
    var vLinePatternBrush = new fabric.PatternBrush(canvas);
    vLinePatternBrush.getPatternSrc = function() {

      var patternCanvas = fabric.document.createElement('canvas');
      patternCanvas.width = patternCanvas.height = 10;
      var ctx = patternCanvas.getContext('2d');

      ctx.strokeStyle = this.color;
      ctx.lineWidth = 5;
      ctx.beginPath();
      ctx.moveTo(0, 5);
      ctx.lineTo(10, 5);
      ctx.closePath();
      ctx.stroke();

      return patternCanvas;
    };

    var hLinePatternBrush = new fabric.PatternBrush(canvas);
    hLinePatternBrush.getPatternSrc = function() {

      var patternCanvas = fabric.document.createElement('canvas');
      patternCanvas.width = patternCanvas.height = 10;
      var ctx = patternCanvas.getContext('2d');

      ctx.strokeStyle = this.color;
      ctx.lineWidth = 5;
      ctx.beginPath();
      ctx.moveTo(5, 0);
      ctx.lineTo(5, 10);
      ctx.closePath();
      ctx.stroke();

      return patternCanvas;
    };

    var squarePatternBrush = new fabric.PatternBrush(canvas);
    squarePatternBrush.getPatternSrc = function() {

      var squareWidth = 10, squareDistance = 2;

      var patternCanvas = fabric.document.createElement('canvas');
      patternCanvas.width = patternCanvas.height = squareWidth + squareDistance;
      var ctx = patternCanvas.getContext('2d');

      ctx.fillStyle = this.color;
      ctx.fillRect(0, 0, squareWidth, squareWidth);

      return patternCanvas;
    };

    var diamondPatternBrush = new fabric.PatternBrush(canvas);
    diamondPatternBrush.getPatternSrc = function() {

      var squareWidth = 10, squareDistance = 5;
      var patternCanvas = fabric.document.createElement('canvas');
      var rect = new fabric.Rect({
        width: squareWidth,
        height: squareWidth,
        angle: 45,
        fill: this.color
      });

      var canvasWidth = rect.getBoundingRectWidth();

      patternCanvas.width = patternCanvas.height = canvasWidth + squareDistance;
      rect.set({ left: canvasWidth / 2, top: canvasWidth / 2 });

      var ctx = patternCanvas.getContext('2d');
      rect.render(ctx);

      return patternCanvas;
    };

    var img = new Image();
    img.src = '../assets/honey_im_subtle.png';

    var texturePatternBrush = new fabric.PatternBrush(canvas);
    texturePatternBrush.source = img;
  }

  $('#drawing-mode-selector').on('change', function() {

    if (this.value === 'hline') {
      canvas.freeDrawingBrush = vLinePatternBrush;
    }
    else if (this.value === 'vline') {
      canvas.freeDrawingBrush = hLinePatternBrush;
    }
    else if (this.value === 'square') {
      canvas.freeDrawingBrush = squarePatternBrush;
    }
    else if (this.value === 'diamond') {
      canvas.freeDrawingBrush = diamondPatternBrush;
    }
    else if (this.value === 'texture') {
      canvas.freeDrawingBrush = texturePatternBrush;
    }
    else {
      canvas.freeDrawingBrush = new fabric[this.value + 'Brush'](canvas);
    }

    if (canvas.freeDrawingBrush) {
      canvas.freeDrawingBrush.color = drawingColorEl.value;
      canvas.freeDrawingBrush.width = parseInt(drawingLineWidthEl.value, 10) || 1;
      canvas.freeDrawingBrush.shadowBlur = parseInt(drawingShadowWidth.value, 10) || 0;
    }
  });

  drawingColorEl.onchange = function() {
    canvas.freeDrawingBrush.color = drawingColorEl.value;
  };
  drawingLineWidthEl.onchange = function() {
    canvas.freeDrawingBrush.width = parseInt(drawingLineWidthEl.value, 10) || 1;
  };
  drawingShadowWidth.onchange = function() {
    canvas.freeDrawingBrush.shadowBlur = parseInt(drawingShadowWidth.value, 10) || 0;
  };

  if (canvas.freeDrawingBrush) {
    canvas.freeDrawingBrush.color = drawingColorEl.value;
    canvas.freeDrawingBrush.width = parseInt(drawingLineWidthEl.value, 10) || 1;
    canvas.freeDrawingBrush.shadowBlur = 0;
  }

  var canvas = new fabric.Canvas('c');
document.getElementById('canvas-background-picker').onchange = function() {
    canvas.backgroundColor = this.value;
    canvas.renderAll();
  };
//end free drawing

请参阅此处的完整屏幕截图,我选择了 vline 模式,但它像简单的铅笔一样绘制 请参阅此处的完整屏幕截图,我选择了 vline 模式,但它像简单的铅笔一样绘制

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1 回答 1

7

我已经更新了你的 jsfiddle,现在它可以工作了Demo

在您的页面上有问题 - 查看您的开发控制台:

  $('#drawing-mode-selector').on('change', function() {
  //Uncaught TypeError: Object [object Object] has no method 'on' 
于 2013-10-24T15:40:48.153 回答