x0, x1 := r.Min.X, r.Max.X
y0, y1 := r.Min.Y, r.Max.Y
for y := y0; y != y1; y++ {
- dpix := dst.Pixel[y]
- for x := x0; x != x1; x++ {
- rgba := dpix[x]
+ dbase := y * dst.Stride
+ dpix := dst.Pix[dbase+x0 : dbase+x1]
+ for i, rgba := range dpix {
dr := (uint32(rgba.R)*a)/m + cr
dg := (uint32(rgba.G)*a)/m + cg
db := (uint32(rgba.B)*a)/m + cb
da := (uint32(rgba.A)*a)/m + ca
- dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
+ dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
}
}
}
x0, x1 := r.Min.X, r.Max.X
y0, y1 := r.Min.Y, r.Max.Y
for y, sy := y0, sp.Y; y != y1; y, sy = y+1, sy+1 {
- dpix := dst.Pixel[y]
- spix := src.Pixel[sy]
- for x, sx := x0, sp.X; x != x1; x, sx = x+1, sx+1 {
- // For unknown reasons, even though both dpix[x] and spix[sx] are
+ dbase := y * dst.Stride
+ dpix := dst.Pix[dbase+x0 : dbase+x1]
+ sbase := sy * src.Stride
+ spix := src.Pix[sbase+sp.X:]
+ for i, rgba := range dpix {
+ // For unknown reasons, even though both dpix[i] and spix[i] are
// image.RGBAColors, on an x86 CPU it seems fastest to call RGBA
// for the source but to do it manually for the destination.
- sr, sg, sb, sa := spix[sx].RGBA()
- drgba := dpix[x]
- dr := uint32(drgba.R)
- dg := uint32(drgba.G)
- db := uint32(drgba.B)
- da := uint32(drgba.A)
+ sr, sg, sb, sa := spix[i].RGBA()
+ dr := uint32(rgba.R)
+ dg := uint32(rgba.G)
+ db := uint32(rgba.B)
+ da := uint32(rgba.A)
// The 0x101 is here for the same reason as in drawRGBA.
a := (m - sa) * 0x101
dr = (dr*a)/m + sr
dg = (dg*a)/m + sg
db = (db*a)/m + sb
da = (da*a)/m + sa
- dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
+ dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
}
}
}
y0, y1 := r.Min.Y, r.Max.Y
cr, cg, cb, ca := src.RGBA()
for y, my := y0, mp.Y; y != y1; y, my = y+1, my+1 {
- dpix := dst.Pixel[y]
- mpix := mask.Pixel[my]
- for x, mx := x0, mp.X; x != x1; x, mx = x+1, mx+1 {
- ma := uint32(mpix[mx].A)
+ dbase := y * dst.Stride
+ dpix := dst.Pix[dbase+x0 : dbase+x1]
+ mbase := my * mask.Stride
+ mpix := mask.Pix[mbase+mp.X:]
+ for i, rgba := range dpix {
+ ma := uint32(mpix[i].A)
if ma == 0 {
continue
}
ma |= ma << 8
- rgba := dpix[x]
dr := uint32(rgba.R)
dg := uint32(rgba.G)
db := uint32(rgba.B)
dg = (dg*a + cg*ma) / m
db = (db*a + cb*ma) / m
da = (da*a + ca*ma) / m
- dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
+ dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
}
}
}
// then use the first row as the slice source for the remaining rows.
dx0, dx1 := r.Min.X, r.Max.X
dy0, dy1 := r.Min.Y, r.Max.Y
- firstRow := dst.Pixel[dy0]
- for x := dx0; x < dx1; x++ {
- firstRow[x] = color
+ dbase := dy0 * dst.Stride
+ i0, i1 := dbase+dx0, dbase+dx1
+ firstRow := dst.Pix[i0:i1]
+ for i, _ := range firstRow {
+ firstRow[i] = color
}
- copySrc := firstRow[dx0:dx1]
for y := dy0 + 1; y < dy1; y++ {
- copy(dst.Pixel[y][dx0:dx1], copySrc)
+ i0 += dst.Stride
+ i1 += dst.Stride
+ copy(dst.Pix[i0:i1], firstRow)
}
}
dx0, dx1 := r.Min.X, r.Max.X
dy0, dy1 := r.Min.Y, r.Max.Y
sx0, sx1 := sp.X, sp.X+dx1-dx0
- for y, sy := dy0, sp.Y; y < dy1; y, sy = y+1, sy+1 {
- copy(dst.Pixel[y][dx0:dx1], src.Pixel[sy][sx0:sx1])
+ d0 := dy0*dst.Stride + dx0
+ d1 := dy0*dst.Stride + dx1
+ s0 := sp.Y*dst.Stride + sx0
+ s1 := sp.Y*dst.Stride + sx1
+ for y := dy0; y < dy1; y++ {
+ copy(dst.Pix[d0:d1], src.Pix[s0:s1])
+ d0 += dst.Stride
+ d1 += dst.Stride
+ s0 += src.Stride
+ s1 += src.Stride
}
}
for y := y0; y != y1; y, sy, my = y+dy, sy+dy, my+dy {
sx := sp.X + x0 - r.Min.X
mx := mp.X + x0 - r.Min.X
- dpix := dst.Pixel[y]
- for x := x0; x != x1; x, sx, mx = x+dx, sx+dx, mx+dx {
+ dbase := y * dst.Stride
+ dpix := dst.Pix[dbase+x0 : dbase+x1]
+ for i, rgba := range dpix {
ma := uint32(m)
if mask != nil {
_, _, _, ma = mask.At(mx, my).RGBA()
sr, sg, sb, sa := src.At(sx, sy).RGBA()
var dr, dg, db, da uint32
if op == Over {
- rgba := dpix[x]
dr = uint32(rgba.R)
dg = uint32(rgba.G)
db = uint32(rgba.B)
db = sb * ma / m
da = sa * ma / m
}
- dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
+ dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
+ sx, mx = sx+dx, mx+dx
}
}
}
At(x, y int) Color
}
-// An RGBA is an in-memory image backed by a 2-D slice of RGBAColor values.
+// An RGBA is an in-memory image of RGBAColor values.
type RGBA struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]RGBAColor
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []RGBAColor
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *RGBA) ColorModel() ColorModel { return RGBAColorModel }
-func (p *RGBA) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
- }
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
-}
+func (p *RGBA) Bounds() Rectangle { return p.Rect }
func (p *RGBA) At(x, y int) Color {
- // TODO(nigeltao): Check if (x,y) is outside the bounds, and return zero.
- // Similarly for the other concrete image types.
- return p.Pixel[y][x]
+ if !p.Rect.Contains(Point{x, y}) {
+ return RGBAColor{}
+ }
+ return p.Pix[y*p.Stride+x]
}
func (p *RGBA) Set(x, y int, c Color) {
- // TODO(nigeltao): Check if (x,y) is outside the bounds, and return.
- // Similarly for the other concrete image types.
- p.Pixel[y][x] = toRGBAColor(c).(RGBAColor)
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toRGBAColor(c).(RGBAColor)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *RGBA) Opaque() bool {
- h := len(p.Pixel)
- if h > 0 {
- w := len(p.Pixel[0])
- for y := 0; y < h; y++ {
- pix := p.Pixel[y]
- for x := 0; x < w; x++ {
- if pix[x].A != 0xff {
- return false
- }
+ if p.Rect.Empty() {
+ return true
+ }
+ base := p.Rect.Min.Y * p.Stride
+ i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ if c.A != 0xff {
+ return false
}
}
+ i0 += p.Stride
+ i1 += p.Stride
}
return true
}
// NewRGBA returns a new RGBA with the given width and height.
func NewRGBA(w, h int) *RGBA {
buf := make([]RGBAColor, w*h)
- pix := make([][]RGBAColor, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &RGBA{pix}
+ return &RGBA{buf, w, Rectangle{ZP, Point{w, h}}}
}
-// An RGBA64 is an in-memory image backed by a 2-D slice of RGBA64Color values.
+// An RGBA64 is an in-memory image of RGBA64Color values.
type RGBA64 struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]RGBA64Color
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []RGBA64Color
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *RGBA64) ColorModel() ColorModel { return RGBA64ColorModel }
-func (p *RGBA64) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *RGBA64) Bounds() Rectangle { return p.Rect }
+
+func (p *RGBA64) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return RGBA64Color{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *RGBA64) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *RGBA64) Set(x, y int, c Color) { p.Pixel[y][x] = toRGBA64Color(c).(RGBA64Color) }
+func (p *RGBA64) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toRGBA64Color(c).(RGBA64Color)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *RGBA64) Opaque() bool {
- h := len(p.Pixel)
- if h > 0 {
- w := len(p.Pixel[0])
- for y := 0; y < h; y++ {
- pix := p.Pixel[y]
- for x := 0; x < w; x++ {
- if pix[x].A != 0xffff {
- return false
- }
+ if p.Rect.Empty() {
+ return true
+ }
+ base := p.Rect.Min.Y * p.Stride
+ i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ if c.A != 0xffff {
+ return false
}
}
+ i0 += p.Stride
+ i1 += p.Stride
}
return true
}
// NewRGBA64 returns a new RGBA64 with the given width and height.
func NewRGBA64(w, h int) *RGBA64 {
- buf := make([]RGBA64Color, w*h)
- pix := make([][]RGBA64Color, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &RGBA64{pix}
+ pix := make([]RGBA64Color, w*h)
+ return &RGBA64{pix, w, Rectangle{ZP, Point{w, h}}}
}
-// A NRGBA is an in-memory image backed by a 2-D slice of NRGBAColor values.
+// An NRGBA is an in-memory image of NRGBAColor values.
type NRGBA struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]NRGBAColor
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []NRGBAColor
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *NRGBA) ColorModel() ColorModel { return NRGBAColorModel }
-func (p *NRGBA) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *NRGBA) Bounds() Rectangle { return p.Rect }
+
+func (p *NRGBA) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return NRGBAColor{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *NRGBA) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *NRGBA) Set(x, y int, c Color) { p.Pixel[y][x] = toNRGBAColor(c).(NRGBAColor) }
+func (p *NRGBA) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toNRGBAColor(c).(NRGBAColor)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *NRGBA) Opaque() bool {
- h := len(p.Pixel)
- if h > 0 {
- w := len(p.Pixel[0])
- for y := 0; y < h; y++ {
- pix := p.Pixel[y]
- for x := 0; x < w; x++ {
- if pix[x].A != 0xff {
- return false
- }
+ if p.Rect.Empty() {
+ return true
+ }
+ base := p.Rect.Min.Y * p.Stride
+ i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ if c.A != 0xff {
+ return false
}
}
+ i0 += p.Stride
+ i1 += p.Stride
}
return true
}
// NewNRGBA returns a new NRGBA with the given width and height.
func NewNRGBA(w, h int) *NRGBA {
- buf := make([]NRGBAColor, w*h)
- pix := make([][]NRGBAColor, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &NRGBA{pix}
+ pix := make([]NRGBAColor, w*h)
+ return &NRGBA{pix, w, Rectangle{ZP, Point{w, h}}}
}
-// A NRGBA64 is an in-memory image backed by a 2-D slice of NRGBA64Color values.
+// An NRGBA64 is an in-memory image of NRGBA64Color values.
type NRGBA64 struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]NRGBA64Color
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []NRGBA64Color
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *NRGBA64) ColorModel() ColorModel { return NRGBA64ColorModel }
-func (p *NRGBA64) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *NRGBA64) Bounds() Rectangle { return p.Rect }
+
+func (p *NRGBA64) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return NRGBA64Color{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *NRGBA64) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *NRGBA64) Set(x, y int, c Color) { p.Pixel[y][x] = toNRGBA64Color(c).(NRGBA64Color) }
+func (p *NRGBA64) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toNRGBA64Color(c).(NRGBA64Color)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *NRGBA64) Opaque() bool {
- h := len(p.Pixel)
- if h > 0 {
- w := len(p.Pixel[0])
- for y := 0; y < h; y++ {
- pix := p.Pixel[y]
- for x := 0; x < w; x++ {
- if pix[x].A != 0xffff {
- return false
- }
+ if p.Rect.Empty() {
+ return true
+ }
+ base := p.Rect.Min.Y * p.Stride
+ i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ if c.A != 0xffff {
+ return false
}
}
+ i0 += p.Stride
+ i1 += p.Stride
}
return true
}
// NewNRGBA64 returns a new NRGBA64 with the given width and height.
func NewNRGBA64(w, h int) *NRGBA64 {
- buf := make([]NRGBA64Color, w*h)
- pix := make([][]NRGBA64Color, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &NRGBA64{pix}
+ pix := make([]NRGBA64Color, w*h)
+ return &NRGBA64{pix, w, Rectangle{ZP, Point{w, h}}}
}
-// An Alpha is an in-memory image backed by a 2-D slice of AlphaColor values.
+// An Alpha is an in-memory image of AlphaColor values.
type Alpha struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]AlphaColor
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []AlphaColor
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *Alpha) ColorModel() ColorModel { return AlphaColorModel }
-func (p *Alpha) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *Alpha) Bounds() Rectangle { return p.Rect }
+
+func (p *Alpha) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return AlphaColor{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *Alpha) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *Alpha) Set(x, y int, c Color) { p.Pixel[y][x] = toAlphaColor(c).(AlphaColor) }
+func (p *Alpha) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toAlphaColor(c).(AlphaColor)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Alpha) Opaque() bool {
- h := len(p.Pixel)
- if h > 0 {
- w := len(p.Pixel[0])
- for y := 0; y < h; y++ {
- pix := p.Pixel[y]
- for x := 0; x < w; x++ {
- if pix[x].A != 0xff {
- return false
- }
+ if p.Rect.Empty() {
+ return true
+ }
+ base := p.Rect.Min.Y * p.Stride
+ i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ if c.A != 0xff {
+ return false
}
}
+ i0 += p.Stride
+ i1 += p.Stride
}
return true
}
// NewAlpha returns a new Alpha with the given width and height.
func NewAlpha(w, h int) *Alpha {
- buf := make([]AlphaColor, w*h)
- pix := make([][]AlphaColor, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &Alpha{pix}
+ pix := make([]AlphaColor, w*h)
+ return &Alpha{pix, w, Rectangle{ZP, Point{w, h}}}
}
-// An Alpha16 is an in-memory image backed by a 2-D slice of Alpha16Color values.
+// An Alpha16 is an in-memory image of Alpha16Color values.
type Alpha16 struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]Alpha16Color
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []Alpha16Color
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *Alpha16) ColorModel() ColorModel { return Alpha16ColorModel }
-func (p *Alpha16) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *Alpha16) Bounds() Rectangle { return p.Rect }
+
+func (p *Alpha16) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return Alpha16Color{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *Alpha16) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *Alpha16) Set(x, y int, c Color) { p.Pixel[y][x] = toAlpha16Color(c).(Alpha16Color) }
+func (p *Alpha16) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toAlpha16Color(c).(Alpha16Color)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Alpha16) Opaque() bool {
- h := len(p.Pixel)
- if h > 0 {
- w := len(p.Pixel[0])
- for y := 0; y < h; y++ {
- pix := p.Pixel[y]
- for x := 0; x < w; x++ {
- if pix[x].A != 0xffff {
- return false
- }
+ if p.Rect.Empty() {
+ return true
+ }
+ base := p.Rect.Min.Y * p.Stride
+ i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ if c.A != 0xffff {
+ return false
}
}
+ i0 += p.Stride
+ i1 += p.Stride
}
return true
}
// NewAlpha16 returns a new Alpha16 with the given width and height.
func NewAlpha16(w, h int) *Alpha16 {
- buf := make([]Alpha16Color, w*h)
- pix := make([][]Alpha16Color, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &Alpha16{pix}
+ pix := make([]Alpha16Color, w*h)
+ return &Alpha16{pix, w, Rectangle{ZP, Point{w, h}}}
}
-// A Gray is an in-memory image backed by a 2-D slice of GrayColor values.
+// An Gray is an in-memory image of GrayColor values.
type Gray struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]GrayColor
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []GrayColor
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *Gray) ColorModel() ColorModel { return GrayColorModel }
-func (p *Gray) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *Gray) Bounds() Rectangle { return p.Rect }
+
+func (p *Gray) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return GrayColor{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *Gray) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *Gray) Set(x, y int, c Color) { p.Pixel[y][x] = toGrayColor(c).(GrayColor) }
+func (p *Gray) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toGrayColor(c).(GrayColor)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Gray) Opaque() bool {
// NewGray returns a new Gray with the given width and height.
func NewGray(w, h int) *Gray {
- buf := make([]GrayColor, w*h)
- pix := make([][]GrayColor, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &Gray{pix}
+ pix := make([]GrayColor, w*h)
+ return &Gray{pix, w, Rectangle{ZP, Point{w, h}}}
}
-// A Gray16 is an in-memory image backed by a 2-D slice of Gray16Color values.
+// An Gray16 is an in-memory image of Gray16Color values.
type Gray16 struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
- Pixel [][]Gray16Color
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []Gray16Color
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
}
func (p *Gray16) ColorModel() ColorModel { return Gray16ColorModel }
-func (p *Gray16) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *Gray16) Bounds() Rectangle { return p.Rect }
+
+func (p *Gray16) At(x, y int) Color {
+ if !p.Rect.Contains(Point{x, y}) {
+ return Gray16Color{}
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Pix[y*p.Stride+x]
}
-func (p *Gray16) At(x, y int) Color { return p.Pixel[y][x] }
-
-func (p *Gray16) Set(x, y int, c Color) { p.Pixel[y][x] = toGray16Color(c).(Gray16Color) }
+func (p *Gray16) Set(x, y int, c Color) {
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = toGray16Color(c).(Gray16Color)
+}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Gray16) Opaque() bool {
// NewGray16 returns a new Gray16 with the given width and height.
func NewGray16(w, h int) *Gray16 {
- buf := make([]Gray16Color, w*h)
- pix := make([][]Gray16Color, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &Gray16{pix}
+ pix := make([]Gray16Color, w*h)
+ return &Gray16{pix, w, Rectangle{ZP, Point{w, h}}}
}
// A PalettedColorModel represents a fixed palette of colors.
// A Paletted is an in-memory image backed by a 2-D slice of uint8 values and a PalettedColorModel.
type Paletted struct {
- // The Pixel field's indices are y first, then x, so that At(x, y) == Palette[Pixel[y][x]].
- Pixel [][]uint8
+ // Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
+ Pix []uint8
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+ // Palette is the image's palette.
Palette PalettedColorModel
}
func (p *Paletted) ColorModel() ColorModel { return p.Palette }
-func (p *Paletted) Bounds() Rectangle {
- if len(p.Pixel) == 0 {
- return ZR
+func (p *Paletted) Bounds() Rectangle { return p.Rect }
+
+func (p *Paletted) At(x, y int) Color {
+ if len(p.Palette) == 0 {
+ return nil
+ }
+ if !p.Rect.Contains(Point{x, y}) {
+ return p.Palette[0]
}
- return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
+ return p.Palette[p.Pix[y*p.Stride+x]]
}
-func (p *Paletted) At(x, y int) Color { return p.Palette[p.Pixel[y][x]] }
-
func (p *Paletted) ColorIndexAt(x, y int) uint8 {
- return p.Pixel[y][x]
+ if !p.Rect.Contains(Point{x, y}) {
+ return 0
+ }
+ return p.Pix[y*p.Stride+x]
}
func (p *Paletted) SetColorIndex(x, y int, index uint8) {
- p.Pixel[y][x] = index
+ if !p.Rect.Contains(Point{x, y}) {
+ return
+ }
+ p.Pix[y*p.Stride+x] = index
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
// NewPaletted returns a new Paletted with the given width, height and palette.
func NewPaletted(w, h int, m PalettedColorModel) *Paletted {
- buf := make([]uint8, w*h)
- pix := make([][]uint8, h)
- for y := range pix {
- pix[y] = buf[w*y : w*(y+1)]
- }
- return &Paletted{pix, m}
+ pix := make([]uint8, w*h)
+ return &Paletted{pix, w, Rectangle{ZP, Point{w, h}}, m}
}