26 lines
475 B
Go
26 lines
475 B
Go
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package main
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import (
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"image"
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"image/color"
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)
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func setAlpha(path string, alpha int) error {
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src, err := decodeImage(path)
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if err != nil {
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return err
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}
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bounds := src.Bounds()
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dst := image.NewNRGBA(bounds)
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for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
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for x := bounds.Min.X; x < bounds.Max.X; x++ {
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c := color.NRGBAModel.Convert(src.At(x, y)).(color.NRGBA)
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if c.A > 0 {
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c.A = uint8(alpha)
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}
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dst.Set(x, y, c)
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}
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}
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return encodePNG(path, dst)
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}
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