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author | Nigel Tao <nigeltao@golang.org> | 2010-10-13 12:05:21 +1100 |
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committer | Nigel Tao <nigeltao@golang.org> | 2010-10-13 12:05:21 +1100 |
commit | 93159e32e775a318192b7cdebc559c57a2a0e39c (patch) | |
tree | d154147c2f851b119b6838bef081776880e34175 | |
parent | 712109f1f1c871498147d1ce44b6cff0b64e03e0 (diff) | |
download | go-93159e32e775a318192b7cdebc559c57a2a0e39c.tar.gz go-93159e32e775a318192b7cdebc559c57a2a0e39c.zip |
image: add an offset to Tiled.
R=r, r2
CC=golang-dev
https://golang.org/cl/2469041
-rw-r--r-- | src/pkg/image/geom.go | 14 | ||||
-rw-r--r-- | src/pkg/image/names.go | 17 |
2 files changed, 15 insertions, 16 deletions
diff --git a/src/pkg/image/geom.go b/src/pkg/image/geom.go index 5a7b0b8a87..ccfe9cdb08 100644 --- a/src/pkg/image/geom.go +++ b/src/pkg/image/geom.go @@ -43,15 +43,13 @@ func (p Point) Div(k int) Point { func (p Point) Mod(r Rectangle) Point { w, h := r.Dx(), r.Dy() p = p.Sub(r.Min) - if p.X >= 0 { - p.X = p.X % w - } else { - p.X = w - 1 - (-1-p.X)%w + p.X = p.X % w + if p.X < 0 { + p.X += w } - if p.Y >= 0 { - p.Y = p.Y % h - } else { - p.Y = h - 1 - (-1-p.Y)%h + p.Y = p.Y % h + if p.Y < 0 { + p.Y += h } return p.Add(r.Min) } diff --git a/src/pkg/image/names.go b/src/pkg/image/names.go index 6900ec9231..c309684cea 100644 --- a/src/pkg/image/names.go +++ b/src/pkg/image/names.go @@ -15,7 +15,7 @@ var ( Opaque = NewColorImage(Alpha16Color{0xffff}) ) -// A ColorImage is a practically infinite-sized Image of uniform Color. +// A ColorImage is an infinite-sized Image of uniform Color. // It implements both the Color and Image interfaces. type ColorImage struct { C Color @@ -43,11 +43,12 @@ func NewColorImage(c Color) *ColorImage { return &ColorImage{c} } -// A Tiled is a practically infinite-sized Image that repeats another Image in -// both directions. Tiled{i}.At(x, y) will equal i.At(x, y) for all points -// within i's Bounds. +// A Tiled is an infinite-sized Image that repeats another Image in both +// directions. Tiled{i, p}.At(x, y) will equal i.At(x+p.X, y+p.Y) for all +// points {x+p.X, y+p.Y} within i's Bounds. type Tiled struct { - I Image + I Image + Offset Point } func (t *Tiled) ColorModel() ColorModel { @@ -57,10 +58,10 @@ func (t *Tiled) ColorModel() ColorModel { func (t *Tiled) Bounds() Rectangle { return Rectangle{Point{-1e9, -1e9}, Point{1e9, 1e9}} } func (t *Tiled) At(x, y int) Color { - p := Point{x, y}.Mod(t.I.Bounds()) + p := Point{x, y}.Add(t.Offset).Mod(t.I.Bounds()) return t.I.At(p.X, p.Y) } -func NewTiled(i Image) *Tiled { - return &Tiled{i} +func NewTiled(i Image, offset Point) *Tiled { + return &Tiled{i, offset} } |