This time I will show you how to edit and operate images on canvas, and what are the precautions for editing and operating images on canvas. The following is a practical case, let's take a look.
This article will be divided into several small functions to introduce canvas image editing in detailZoom
The following is an analysis chart. It is assumed that by default, the image and canvas have the same width and height. The scale range of the image is 0.5 to 3. What changes when scaling is the size and coordinate position of the image1 2 3 4 |
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to add the picture and watermark, and use toDataURL() and the a tag to download the watermarked picture. Function
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Magnifying glass effect Mainly uses the technology of off-screen canvas. The off-screen canvas places a magnified version of the picture, while the ordinary canvas places the normal version of the picture
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