HTML Canvas中的getPixel?

是否可以查询HTML Canvas对象以获取特定位置的颜色?

回答:

W3C文档中有关于像素操纵的部分。

这是有关如何反转图像的示例:

var context = document.getElementById('myCanvas').getContext('2d');

// Get the CanvasPixelArray from the given coordinates and dimensions.

var imgd = context.getImageData(x, y, width, height);

var pix = imgd.data;

// Loop over each pixel and invert the color.

for (var i = 0, n = pix.length; i < n; i += 4) {

pix[i ] = 255 - pix[i ]; // red

pix[i+1] = 255 - pix[i+1]; // green

pix[i+2] = 255 - pix[i+2]; // blue

// i+3 is alpha (the fourth element)

}

// Draw the ImageData at the given (x,y) coordinates.

context.putImageData(imgd, x, y);

以上是 HTML Canvas中的getPixel? 的全部内容, 来源链接: utcz.com/qa/423197.html

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