as shown in the picture, many chat bubbles have a small triangle pointing to the avatar. If it is a text bubble, you can use a small triangle of the same color as the chat bubble. But what about the picture? How to fill this small triangle with the background of the picture? It can be seen that the column of the small triangle is covered, revealing only the picture in the small triangle.
take Wechat as an example. From what I know so far, only sharing, Mini Program sharing and text will have a triangle pointing to users, and there are no pictures sent by themselves.
you can use the getImageData method in canvas to get the background color of the image boundary, and then fill the small triangle
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