diff options
Diffstat (limited to 'src/pkg/image/image.go')
| -rw-r--r-- | src/pkg/image/image.go | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/src/pkg/image/image.go b/src/pkg/image/image.go index 4350acc82..1bdac36f5 100644 --- a/src/pkg/image/image.go +++ b/src/pkg/image/image.go @@ -58,6 +58,16 @@ func (p *RGBA) SetRGBA(x, y int, c RGBAColor) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *RGBA) SubImage(r Rectangle) Image { + return &RGBA{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *RGBA) Opaque() bool { if p.Rect.Empty() { @@ -117,6 +127,16 @@ func (p *RGBA64) SetRGBA64(x, y int, c RGBA64Color) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *RGBA64) SubImage(r Rectangle) Image { + return &RGBA64{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *RGBA64) Opaque() bool { if p.Rect.Empty() { @@ -176,6 +196,16 @@ func (p *NRGBA) SetNRGBA(x, y int, c NRGBAColor) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *NRGBA) SubImage(r Rectangle) Image { + return &NRGBA{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *NRGBA) Opaque() bool { if p.Rect.Empty() { @@ -235,6 +265,16 @@ func (p *NRGBA64) SetNRGBA64(x, y int, c NRGBA64Color) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *NRGBA64) SubImage(r Rectangle) Image { + return &NRGBA64{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *NRGBA64) Opaque() bool { if p.Rect.Empty() { @@ -294,6 +334,16 @@ func (p *Alpha) SetAlpha(x, y int, c AlphaColor) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *Alpha) SubImage(r Rectangle) Image { + return &Alpha{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *Alpha) Opaque() bool { if p.Rect.Empty() { @@ -353,6 +403,16 @@ func (p *Alpha16) SetAlpha16(x, y int, c Alpha16Color) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *Alpha16) SubImage(r Rectangle) Image { + return &Alpha16{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *Alpha16) Opaque() bool { if p.Rect.Empty() { @@ -412,6 +472,16 @@ func (p *Gray) SetGray(x, y int, c GrayColor) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *Gray) SubImage(r Rectangle) Image { + return &Gray{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *Gray) Opaque() bool { return true @@ -457,6 +527,16 @@ func (p *Gray16) SetGray16(x, y int, c Gray16Color) { p.Pix[y*p.Stride+x] = c } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *Gray16) SubImage(r Rectangle) Image { + return &Gray16{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *Gray16) Opaque() bool { return true @@ -544,6 +624,17 @@ func (p *Paletted) SetColorIndex(x, y int, index uint8) { p.Pix[y*p.Stride+x] = index } +// SubImage returns an image representing the portion of the image p visible +// through r. The returned value shares pixels with the original image. +func (p *Paletted) SubImage(r Rectangle) Image { + return &Paletted{ + Pix: p.Pix, + Stride: p.Stride, + Rect: p.Rect.Intersect(r), + Palette: p.Palette, + } +} + // Opaque scans the entire image and returns whether or not it is fully opaque. func (p *Paletted) Opaque() bool { for _, c := range p.Palette { |