Javascript 丰原陈庄稼人的庄稼是椭圆形的吗?
裁剪圆时,我尝试设置Javascript 丰原陈庄稼人的庄稼是椭圆形的吗?,javascript,canvas,Javascript,Canvas,裁剪圆时,我尝试设置crapper.setAspectRatio(0)允许我自由拖动以获得椭圆形状,但当它裁剪时,我最终得到的是圆形裁剪,但透明的边填充了额外缺少的信息。此图像应为width=722px height=182px 下面是获取圆形画布的函数,该函数适用于完美的圆形,但不适用于椭圆: function getRoundedCanvas(sourceCanvas) { var canvas = document.createElement('canvas'); var con
crapper.setAspectRatio(0)
允许我自由拖动以获得椭圆形状,但当它裁剪时,我最终得到的是圆形裁剪,但透明的边填充了额外缺少的信息。此图像应为width=722px height=182px
下面是获取圆形画布的函数,该函数适用于完美的圆形,但不适用于椭圆:
function getRoundedCanvas(sourceCanvas) {
var canvas = document.createElement('canvas');
var context = canvas.getContext('2d');
var width = sourceCanvas.width;
var height = sourceCanvas.height;
canvas.width = width;
canvas.height = height;
context.imageSmoothingEnabled = true;
context.drawImage(sourceCanvas, 0, 0, width, height);
context.globalCompositeOperation = 'destination-in';
context.beginPath();
context.arc(width / 2, height / 2, Math.min(width, height) / 2, 0, 2 * Math.PI, true);
context.fill();
return canvas;
}
我能够对其进行一些修改以使其正常工作:
function getRoundedCanvas(sourceCanvas) {
var canvas = document.createElement('canvas');
var context = canvas.getContext('2d');
offsetTop = Math.round(cropper.getCropBoxData().top);
offsetLeft = Math.round(cropper.getCropBoxData().left);
var width = sourceCanvas.width;
var height = sourceCanvas.height;
canvas.width = width;
canvas.height = height;
context.imageSmoothingEnabled = true;
context.drawImage(sourceCanvas, 0, 0, width, height);
context.globalCompositeOperation = 'destination-in';
context.beginPath();
context.ellipse(width/2, height/2, width/2, height/2, 0 * Math.PI, 0, 45 * Math.PI);
context.fill();
return canvas;
}