47 lines
876 B
Go
47 lines
876 B
Go
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package imageutils
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import (
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"image"
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"image/color"
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)
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type rescaled struct {
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src image.Image
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scale int
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}
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// ColorModel implements image.Image interface
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func (r rescaled) ColorModel() color.Model {
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return r.src.ColorModel()
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}
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// Bounds implements image.Image interface
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func (r rescaled) Bounds() image.Rectangle {
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b := r.src.Bounds()
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return image.Rectangle{
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Min: image.Point{
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X: b.Min.X,
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Y: b.Min.Y,
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},
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Max: image.Point{
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X: b.Max.X * r.scale,
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Y: b.Max.Y * r.scale,
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},
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}
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}
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// At implements image.Image interface
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func (r rescaled) At(x, y int) color.Color {
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return r.src.At(x/r.scale, y/r.scale)
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}
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// Scale scales image.Image to a given scale
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// and then returns image.Image.
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// For now it will work only with positive integers.
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func Scale(img image.Image, scale int) image.Image {
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if scale < 1 {
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scale = 1
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}
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return rescaled{img, scale}
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}
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