【GoLang笔记】A Tour of Go - Exercise: Images

2019-04-15 13:08发布

本笔记是GoLang学习教程的一道习题,题目要求及一种参考实现如下所示。 备注:由于天朝GFW屏蔽了GAE,所以GoLang官网及学习教程需要翻墙才能访问。 Exercise: Images
Remember the picture generator you wrote earlier? Let's write another one, but this time it will return an implementation of image.Image instead of a slice of data.
Define your own Image type, implement the necessary methods, and call pic.ShowImage.
Bounds should return a image.Rectangle, like image.Rect(0, 0, w, h).
ColorModel should return color.RGBAModel.
At should return a color; the value v in the last picture generator corresponds to color.RGBA{v, v, 255, 255} in this one.
参考实现如下:
package main import ( "code.google.com/p/go-tour/pic" "image" "image/color" ) type Image struct{ x, y, w, h int v uint8 } func (img Image) ColorModel() color.Model { return color.RGBAModel } func (img Image) Bounds() image.Rectangle { return image.Rect(0, 0, img.w, img.h) } func (img Image) At(x, y int) color.Color { return color.RGBA{img.v, img.v, 255, 255} } func main() { m := Image{1, 2, 200, 30, 11} pic.ShowImage(m) }
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