imagefn - empty.go

     1  package imagefn // import "vimagination.zapto.org/imagefn"
     2  
     3  import (
     4  	"image"
     5  	"image/color"
     6  )
     7  
     8  type empty struct {
     9  	color.Model
    10  	Min image.Point
    11  }
    12  
    13  func newEmpty(i image.Image) image.Image {
    14  	e := empty{
    15  		Model: i.ColorModel(),
    16  		Min:   i.Bounds().Min,
    17  	}
    18  	if _, ok := i.(setter); ok {
    19  		return &emptySet{
    20  			empty: e,
    21  		}
    22  	}
    23  	return &e
    24  }
    25  
    26  func (e empty) ColorModel() color.Model {
    27  	return e.Model
    28  }
    29  
    30  func (e empty) Bounds() image.Rectangle {
    31  	return image.Rectangle{e.Min, e.Min}
    32  }
    33  
    34  func (e empty) At(x, y int) color.Color {
    35  	return e.Model.Convert(color.Alpha{})
    36  }
    37  
    38  type emptySet struct {
    39  	empty
    40  }
    41  
    42  func (emptySet) Set(_, _ int, _ color.Color) {}