CamanJS恢复和旋转修复

Question

如果在CamanJS中使用旋转插件，则在试图还原更改时会出现问题。只有在裁剪或调整图像大小时才能很好地实现Caman，而不是当您旋转图像时。当您恢复和图像旋转时，图像重新加载扭曲，因为它没有考虑到画布已经旋转和改变大小。另外，画布的imageData.data现在也不同了。所以我想我是通过观察他是如何实现调整尺寸的。我所做的(他也做过)基本的事情是：

1. 创建处于初始状态的画布
2. 从pixelData更新他的initialState
3. 创建一个新画布
4. 用最初的图像旋转他
5. 获取ImageData并重新修改它们

所以我说的是。我需要知道图像旋转了多少个角度，以便在旋转新画布时得到正确的imageData (步骤4)。

this.angle=0; //added it in the constructor

我还在构造函数中添加了一个新的布尔值，以告诉我是否旋转了画布。

this.rotated = false;

在旋转插件中：

Caman.Plugin.register("rotate", function(degrees) {
    //....
    //....
    //....
    this.angle += degrees;
    this.rotated = true;
    return this.replaceCanvas(canvas);
}

在originalVisiblePixels原型上：

else if (this.rotated){
    canvas = document.createElement('canvas');//Canvas for initial state
    canvas.width = this.originalWidth; //give it the original width
    canvas.height = this.originalHeight; //and original height
    ctx = canvas.getContext('2d');
    imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
    pixelData = imageData.data;//get the pixelData (length equal to those of initial canvas      
    _ref = this.originalPixelData; //use it as a reference array
    for (i = _i = 0, _len = _ref.length; _i < _len; i = ++_i) {
        pixel = _ref[i];
        pixelData[i] = pixel; //give pixelData the initial pixels
    }
    ctx.putImageData(imageData, 0, 0); //put it back on our canvas
    rotatedCanvas = document.createElement('canvas'); //canvas to rotate from initial
    rotatedCtx = rotatedCanvas.getContext('2d');
    rotatedCanvas.width = this.canvas.width;//Our canvas was already rotated so it has been replaced. Caman's canvas attribute is allready rotated, So use that width
    rotatedCanvas.height = this.canvas.height; //the same
    x = rotatedCanvas.width / 2; //for translating
    y = rotatedCanvas.width / 2; //same
    rotatedCtx.save();
    rotatedCtx.translate(x, y);
    rotatedCtx.rotate(this.angle * Math.PI / 180); //rotation based on the total angle
    rotatedCtx.drawImage(canvas, -canvas.width / 2, -canvas.height / 2, canvas.width, canvas.height); //put the image back on canvas
    rotatedCtx.restore(); //restore it
    pixelData = rotatedCtx.getImageData(0, 0, rotatedCanvas.width, rotatedCanvas.height).data; //get the pixelData back       
    width = rotatedCanvas.width; //used for returning the pixels in revert function               
}

您还需要在重置原型函数中添加一些重置。基本复位角和旋转

Caman.prototype.reset = function() {
    //....
    //....
    this.angle = 0;
    this.rotated = false;
}

仅此而已。

我用过它至今还在工作。你觉得呢?希望能帮上忙

Answer 1

谢谢你，在做了一个小小的改变之后，它就起作用了。

在originalVisiblePixels原型内部的else语句中，我进行了更改：

x = rotatedCanvas.width / 2; //for translating
y = rotatedCanvas.width / 2; //same

至：

x = rotatedCanvas.width / 2; //for translating
y = rotatedCanvas.height/ 2; //same

在此之前，我的图像被切割。